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International Review of Mechanical Engineering  Vol. 6 N. 3-- Part A

International Review of Mechanical Engineering  Vol. 6 N. 3-- Part B



go to top   International Review of Mechanical Engineering - March  2012 (Vol. 6 N. 3) - Papers Part A 




go to top   International Review of Mechanical Engineering - March  2012 (Vol. 6 N. 3) - Papers Part B 


Special Section on Regional Conference on Automotive Research (ReCAR2011) 




International Review of Mechanical Engineering - Papers- Part A



go to top   Mechanical Modeling of the not Welded Tubular Y and T-joints of the Offshore Steels
         by S. Belhour, A. Bellaouar, M. Benidir, M. Lachi

        Vol. 6 n. 3, pp. 302-307


Abstract - In this work a numerical modeling with ANSYS program of the mechanical behavior of the not welded tubular junction structures of the offshore has been considered. The objective is to determine the stress field and displacement of the structure in particular, at the chord/brace intersection of the Y-joint and T-joint under the action of wind and sea wave.

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Keywords:  Constraints and Displacements, Finite Elements Method, Junctions, Modeling, Offshore Platform, Steel, Stress Distribution, Tubular.



go to top     Experimental Study of a Solar Ejector Heat Pump
         by S. Maalej, M. C. Zaghdoudi, H. Salhi

         Vol. 6 n. 3, pp. 308-319


Abstracts – A high-performance Solar Ejector Heat Pump (SEHP) using R141b as the working fluid was developed. The feature of such a system is the possibility of using a low-grade heat source such as solar energy heat to operate the system. The influence of boiler, condenser, and evaporator temperatures on the system heat transfer is investigated experimentally under different operating conditions. The coefficient of performance (COP) increases with the evaporation and boiler temperatures. For the heating mode, the coefficient of performance enhancement reaches approximately 25% when the evaporation temperature increases from 8 °C to 11 °C and the boiler temperature is 90 °C. For the cooling mode, the COP enhancement is very sensitive to the evaporation temperature and reaches nearly 100% when the evaporation temperature increases from 8°C to 11 °C with a boiler temperature of 90 °C.
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Keywords: Solar Ejector Cooling Machine, Refrigerating Machines, Solar Vacuum Tube Collector, Heat Pipes.



go to top     Heterogeneous Femur Model Reconstruction for Improved FEA Analysis
        by Suleiman Obeidat, Casmir Agbaraji , Wisam Abu Jadayil, Nabeel Mandahawi

         Vol. 6 n. 3, pp. 320-324

Abstract – The objective of this research is to reconstruct the femur bone as a heterogeneous model and to examine the mechanical response of the proximal femur bone under mechanical loading using finite element analysis. Contrary to setting a uniform Young’s modulus for the femur bone during analysis, the femur bone was reconstructed as a layered heterogeneous model with each layer having its own assigned Young’s modulus. Computerized Axial Tomography (CT) slices of a fresh frozen femur of a 30 year old male donor were downloaded from (www.bgu.ac.il/~zohary/CT_FF.html) which were uploaded by Yosibash et al. (2007a). The images were imported into MIMICS 11.02 and used to convert 2-D CT scans into a layered 3-D Stereolithography (STL) image. The proximal femur was divided into ten layers in the longitudinal direction of the proximal femur based on their Hounsfield unit (HU) values. The Hounsfield unit obtained from MIMICS was used to calculate the density of the bone as well as the corresponding Young’s modulus. Constant Poisson’s ratio of 0.3 was used in the simulation. It is hypothesized that by including the variation in density within the finite element analysis model (FEA), it would be possible to replicate the experimental results obtained by Yosibash et al. (2007a).

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Keywords: Femur Bone, Heterogeneous Modeling, Computerized Axial Tomography.



go to top   Effects of Micro and Nano Sized Alumina Fillers in Silicone Rubber
         by N.Loganathan, S.Chandrasekar

         Vol. 6 n. 3, pp. 325-331


Abstract - This paper discusses the experimental results in an effort to understand the tracking and erosion resistance of the micro size and nano size Al2O3 filled silicone rubber (SIR) material which has been studied under the AC voltages, with ammonium chloride as a contaminant, as per IEC 60587 test procedures. The characteristic changes in the tracking resistance of the micro and nano size filled specimens are analyzed through leakage current measurement and the eroded mass are used to evaluate the relative erosion and tracking resistance of the composites. The fundamental and third harmonic of the leakage current during the tracking study were analyzed using moving average current technique. It is observed that the harmonic components of leakage current show good correlation with the tracking and erosion resistance of the material. The thermogravimetry- derivative thermo gravimetric (TG-DTG) studies were performed to understand the thermal degradation of micro and nano filled SIR material. The obtained results indicate the performance of nano filled SIR were better than the micro filled SIR material. The scanning electron microscope (SEM) with Energy Dispersive X-ray analysis (EDAX) was used to examine the dispersion and physical bonding between micro and nano Al2O3 fillers on the silicone rubber matrix. This mechanism result shows the good correlation with the tracking and erosion resistance of the nano-filled SIR materials.
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Keywords: Leakage Current, Nano Filler, Outdoor Insulator, Silicone Rubber, Tracking Resistance, Third Harmonic.



go to top   Influence of the Chemical Composition and Pressure of the Compressing on Some Physical and Mechanical Properties of Ceramic Matrix Composite
         by Raed N. Razzoqi, Lutfy A. Mahmood, Mohammed S. Ahmed, Shymaa M. Fayyadh

         Vol. 6 n. 3, pp. 332-338


Abstract - Mankind used the overlapped materials for several centuries to meet his daily life requirements because of the properties of these materials that made them occupy large areas. This research dealt with the preparation of the compounds (A,B,C,D,E) of the chemical composition (50%SiO2, 40%Al, 5%Co, 5%Ni) , (40%SiO2, 40%Al, 5%Co, 5%Ni, 10%Fe), (40%SiO2, 40%Al, 5%Co, 5%Ni, 10%Mn) , (40%SiO2, 40%Al, 5%Co, 5%Ni, 10%Cu) , (40%SiO2, 40%Al, 5%Co, 5%Ni, 10%Ag) respectively. In order to prepare samples,powder metallurgy technique had been used. The effect of compressing pressure, to form samples, on its physical and mechanical properties had been studies. It had been used a range of compressing pressures (2,3,4,5,6) tons for (60 Sec) and sintering the samples in temperature (1000C0) for (10 hours). Then many physical tests had been performed ( apparent porosity, the rate of water absorption, apparent density, specific gravity), as well as the mechanical tests, which included hardness and resistance to compression. It was shown that, the effect of compressing pressure on both the apparent porosity and the rate of water absorption, is a negative effect for all composites, except the composite A at a compressing pressure of (6 ton), while it has a positive impact on the apparent density and specific gravity. It was concluded that,increasing the amount of SiO2 in forming the composite A, works on having the highest values for the apparent porosity and the rate of water absorption,and the lowest values for the apparent density and specific gravity. While silver in the composite E has an opposite effect. The composite D had the highest values for hardness and resistance to compression for all the compressing pressures compared with the rest of the composites . upon measuring the values of these two properties at a compressing pressure of (2ton), (6ton), their rates have increased to (9.60%, 51.7%) respectively. At increasing the compressing pressure, the mechanical properties improved for all composites, except the two composites A, B , as they failed to resist compression at compressing pressure of (5ton) .

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Keywords: Composites , Compressing Pressure, Physical Properties, Mechanical Properties, Powder Metallurgy Technique.



go to top   Classroom Comfort Ability Assessment: A Case Study
         by Z.A. Zailani, R. Hamidon, M.S. Hussin, M.F.M.A. Hamzas, Hasnul Hadi

         Vol. 6 n. 3, pp. 339-345


Abstract - This study was conducted to evaluate the comfort level of an air-conditioned classroom at the School of Manufacturing Engineering campus using objective measurement, subjective assessment and Computational Fluid Dynamics (CFD) modeling. CFD software namely FLUENT was used to simulate the comfort parameter such as temperature and air velocity. Corroboration between results from objective measurement, subjective assessment and CFD modeling was conducted. The results obtained showed that measured temperature and relative humidity were within the standard comfort condition by ISO EN7730 (1994) while air velocity exceeded the standard limit by ISO EN7730 (1994). The overall comfort vote, Predicted Mean Vote (PMV) and Predicted Percentage Dissatisfied (PPD) indices shows that occupants are comfortable and satisfied with the classroom comfort level. In addition, some recommendations were made to improve the comfort level and also to reduce carbon dioxide (CO2) concentration built up in the classroom.
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Keywords: Objective Measurement, Subjective Assessment, Computational Fluid Dynamics (CFD) Modeling, Predicted Mean Vote (PMV), Predicted Percentage Dissatisfied (PPD).



go to top   Review of Experimental Investigation in Heat Transfer for Jet Impingement Cooling
         by Ingole S. B., K. K. Sundaram

         Vol. 6 n. 3, pp.  346-356


Abstract - Jet impingement in electronics cooling is highly effective for field applications because of its implementation simplicity. The paper reviews and categorizes the broad variety of experimental researches carried out with different configurations. Analytical views are discussed on fluid selection in jet configurations and methodologies for selecting different fluids like air, water, and even mist systems are considered. Behavior of fluid flow patterns depends upon geometry of surface and nozzle used. Nozzles of circular, slot, inner swirled type, insert type, cusped ellipse type, are reported with different nozzle to target spacing at varied Reynolds numbers which help in obtaining the average Nusselt number. Cooling with inclined jet or surface is also analyzed by few researchers using wind tunnel and duct. For solving various electronics cooling problems, discrete heat source cooling, flow pattern analysis, spent jet analysis, synthetic jet, confined and free jets, micro jets at various Reynolds Number ranging from laminar to turbulent flow are noted. It is observed that no typical standards are available to select particular type of jet cooling for an application.

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Keywords: Jet Classification, Jet Impingement Cooling, Jet Heat Transfer, Nusselt Number.



go to top   Viscous Dissipation Effects in a Free Convective Flow over Vertical Plate with Radiation and Chemical Reaction
         by P. Ganesan, P. Loganathan, R. K. Suganthi

         Vol. 6 n. 3, pp. 357-363


Abstract - An analysis is performed to study the effects of viscous dissipation in a transient, free convective flow of a viscous, incompressible fluid past an isothermal vertical plate in the presence of radiation and chemical reaction. The Rosseland approximation is used to describe the radiative heat transfer in the limit of an optically thick fluid. The governing boundary layer equations are solved numerically by applying an implicit finite difference scheme of Crank-Nicolson type. A parametric study is performed to illustrate the influence of radiation parameter, Eckert number, Prandtl number, Schmidt number and chemical reaction parameter on the velocity, temperature and concentration profiles. It is observed that an increase in radiation parameter decreases the velocity and temperature profiles while an increase in Eckert number increases the velocity and temperature profiles. As well, an increase in the chemical reaction parameter increases the temperature while decreases the velocity and concentration profiles. The effects of the parameters on local and average skin-friction coefficient, Nusselt number and Sherwood number are also studied and presented graphically.

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Keywords: Chemical Reaction, Isothermal, Radiation, Transient, Viscous Dissipation.



go to top   Effect of Alkali Treatment and Fiber Content on the Mechanical Characteristics of Cement/Date Palm Fibers Composite DPLF
         by K. Harrat, N. Chelghoum, M. Hidjeb, M. Quenneudec

         Vol. 6 n. 3, pp. 364-371


Abstract - Biodegradable and renewable vegetable fibers are characterized by their high tensile strength, lightness and ductility. Incorporating date palm fibers in a cement matrix composite provides some interesting properties. The aim of the present article is to investigate the use of a widely abundant date palm leaves fiber (DPLF) as an alternative reinforcement in cement composite material. Raw DPLF underwent different surface modification methods such as heat and alkali treatments to eliminate sugar and fats and also degrades the hemicelluloses to improve fiber roughness. Several formulations of DPLF-cement composite specimen were tested and analyzed. The samples with treated fiber showed a ductile and flexible material. Physical, mechanical properties and durability obtained lets suggest their use in insulation and construction even in seismic zones.
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Keywords: Cement Composite, Date Palm Leaves, Treatment, Strength, Ductility, Durability.



go to top   Warpage Optimization on Ultra Thin Plate in Three Plate Mold for PP, ABS & ABS+PC Materials by Using Taguchi Method
        by S.M. Nasir, N. A. Shuaib, Z. Shayfull, M. Fathullah, Z. Nooraizedfiza

        Vol. 6 n. 3, pp. 372-378


Abstract - The parameters setting of process conditions in injection molding process is very importance to ensure the quality of molded components is controlled by minimizing of any defects such as warpage. Various injection parameters were examined and the best setting for different materials such as Polypropylene (PP), Acrylonitrile Butadiene Styrene (ABS) and Acrylonitrile Butadiene Styrene + Polycarbonate (ABS+PC) is identified which collectively affect the warpage on ultra thin plate plastic component using Taguchi and ANOVA methods. For this purpose, Autodesk Moldflow Insight (AMI) software was used to analyze the process parameters based L9 Orthogonal Array designed by Taguchi. The four parameters consist of Mold Temperature, Melt Temperature, Packing Pressure and Packing Time. The Signal to Noise (S/N) ratio method was applied in identifying the best parameter settings and to find the influence of these parameters on warpage issue. In this study, packing pressure was found to be the most significant parameter, regardless of types of material used.

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Keywords: Ultra Thin Plate, Injection Molding, Warpage, Taguchi Method, ANOVA.



go to top   Maintenance based on Conditions of Machinery and Equipment in the Ceramic Industry
         by V. Bristot, V. Bristot, L. Schaeffer, V. Gruber, J. Alves

         Vol. 6 n. 3, pp. 379-383


Abstract - This paper investigated how plants develop leading-edge maintenance to reduce downtime due to maintenance. This increases the quality and productivity, avoiding delay in delivery of products and satisfying customer needs. In addition to the TPM-Total Productive Maintenance, there is another system based on the conditions of maintenance of machinery and equipment, performing maintenance when needed, which can be called the Routine Maintenance. This system avoids the maintenance based on the estimated useful life of equipment that can perform maintenance prior to the time necessary, and after the break. A quantitative survey conducted in factories of ceramic plates, and identified the high potential need for implementing a system of routine maintenance.

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Keywords:  Routine Maintenance, Productivity, Reduce Downtime.



go to top  Model for Determining the Clamping Force in Expanding Mandrels for High–Speed Turning
         by E.Soriano, M. B. Ramírez, H. Rubio

         Vol. 6 n. 3, pp. 384-389

Abstract - Modern manufacturing engineering can hardly do without mandrels. In precision machining, turning, grinding, toothcutting and inspection, expanding mandrels are used for works with high requirements. The many different applications mean that there must be many different types ranging from hand-operated or power-assisted models through Morse taper or flange seat types, to various clamping ranges and various sundry special features such as self-locking clamps or workpiece stops with or without air sensing.
This paper develops a novel analytical model for expanding mandrels. This paper first presents the analytical model to describe the operating principle of the expanding mandrels and the characteristics of the clamping/unclamping operation. Second, it presents the finite element method (FEM) analyses that were conducted to check the developed analytical model.
The basic problem with the application of jaw-chucks for clamping workpieces during high-speed turning is the huge centrifugal force that acts on jaws. This centrifugal force reduces effectiveness of the clamping force, making the HSC process dangerous. With the application of expanding mandrels centrifugal force has not negative influence
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Keywords: Expanding Mandrel, Machine-Tool Fixture, Clamping Force, Finite Element Method.



go to top   The Effect of the Machining Parameters on the Micro Hardness and Residual Stresses in the Turning of Nimonic C-263 Alloy
         by C.Ezilarasan, V.S. Senthil Kumar

         Vol. 6 n. 3, pp. 390-396


Abstract - This paper investigates the surface integrity, in terms of the micro hardness and residual stresses, in the turning of the nickel-based super alloy Nimonic C-263. The generation of micro hardness and residual stresses as a function of depth have been analysed for a series of machining trials, using PVD coated carbide inserts. Investigations have shown that while machining the nimonic C-263 alloy, the properties of the work material (thermal conductivity), its microstructure and cutting conditions play a vital role in the deformation mechanism, and the degree of hardening of the machined surface. The cutting speed and machining time have a predominant effect on the level of micro hardness and residual stresses.

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Keywords: C-263 Alloy, Turning, Surface Integrity, Micro Hardness, Residual Stresses (RS), Tensile Residual Stresses, Compressive Residual Stresses.



go to top   Soret and Dufour Effects on Natural Convection in Power-law Fluid Saturated Porous Medium
         by D. Srinivasacharya, G.Swamy Reddy

         Vol. 6 n. 3, pp. 397-404


Abstract - The heat and mass transfer characteristics of natural convection along a vertical plate embedded in power-law fluid saturated Darcy porous medium in the presence of Soret and Dufour effects is studied. The governing partial differential equations are transformed into ordinary differential equations using similarity transformations and then solved using shooting method. A parametric study of the physical parameters involved in the problem is conducted and a representative set of numerical results is illustrated graphically.
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Keywords: Natural Convection, Boundary Layer, Darcy Porous Medium, Power-Law Fluid, Soret and Dufour Effects, Self-similarity .


go to top   Optimization of Tool Life Using Linear Regression Analysis
         by Sriram Srinivasan, R.Sathyanarayan, L.Srivatsan, Dr.B.Vijaya Ramnath

         Vol. 6 n. 3, pp. 405-410


Abstract - The main aim of industries in the present scenario is to increase their rate of production in order to meet the increase in demand. The major problems faced by manufacturers are machine idle time, frequent replacement of tool due to wear and breakdown. These problems lead to increase in the idling time of production machines thereby causing considerable decrease in the rate of production. Hence, the need for optimization of tool life has become necessary. This paper involves a linear regression analysis to increase the effectiveness of the tool. For this purpose an experiment was conducted by considering the factors affecting the performance of the tool. In this analysis, five factors such as depth of cut, feed rate, cutting speed, hardness of tool and tool geometry has been taken and their effect on tool life are analyzed. In this paper, all the factors have been analyzed separately by keeping other factors as constant, thereby enabling a brief analysis on factors affecting tool life. By the above procedure the factor which has the most influence on the tool life has been determined.
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Keywords: Linear Regression Analysis, Production Time, Tool Life, Multivariate Analysis.



go to top   Spectral Analysis of Various Implementations of the Exponential Wide Band Model (EWBM) for H2O-CO2 Mixtures
         by Alexander Maximov, Mohammad Hadi Bordbar, Timo Hyppänen

         Vol. 6 n. 3, pp. 411-419


Abstract - Two different formulations of the exponential wide band model (EWBM) were used to calculate the total and spectral emissivity of H2O-CO2 gas mixtures under the air-fired combustion conditions. The first one was the original wide band method with the four region equation (EWBM-4RE), and the second was the numerical integration method (EWBM-IM). Using the statistical narrow band model (SNBM) as a benchmark along with some experimental data, the accuracy of various implementations of the EWBM was analyzed. Generally, the EWBM-IM has more potentiality for spectral predictions. As opposite to the EWBM-4RE, the EWBM-IM approximately reproduces the shape of absorption spectrum of H2O and CO2. The accuracy analysis of both formulations of the EWBM was done by applying them to a benchmark which represents the radiative heat transfer in real participating gas in a two-dimensional rectangular enclosure. The EWBM-4RE accompanied with the original spectral parameters was found to be a more accurate model than EWBM-IM for being used in the gray gas radiative modeling. However, the accuracy of the EWBM-IM in the calculation of the total properties could be improved by deriving the new spectral band parameters for EWBM-IM instead of using those which were developed to be used in the original EWBM-4RE.
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Keywords: Statistical Narrow Band Model, Absorption Coefficient, Exponential Wide Band Model, Integration Method, H2O-CO2 Mixtures, Spectral Absorption.



go to top   Entransy and its Utilization in Problems of Thermodynamics and Heat Transfer
         by Santiago del Rio Oliveira, Luiz Fernando Milanez

         Vol. 6 n. 3, pp. 420-431


Abstract - The concept of entransy was recently proposed in terms of the analogy to the electric energy stored in a capacitor. The entransy of a system describes its heat transfer ability, as the exergy of a system quantifies its work production potential. Hence, the concept of entransy can be useful in problems where the heat transfer is the main objective, as for example, in systems collecting solar energy. This concept is quite recent and there are only a few works related to this topic. It is expected, however, that this approach will soon be used more often in the analysis of problems in thermodynamics and heat transfer. The objective of this work is to present a review of the concept of entransy in a systematic way, beginning with its definition, balance equations and a few examples of simple applications. It is hoped that this concept of entransy becomes a useful tool in the analysis and design of more efficient thermal systems.
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Keywords: Entransy, Thermodynamics, Heat Transfer, Entropy, Exergy.



go to top   Multi-objective Optimization of Grillages Using Adaptive Genetic Algorithm
         by D. Mačiūnas, R. Belevičius

         Vol. 6 n. 3, pp. 432-439


Abstract - The paper proposes a technology for multi-objective global optimization of grillage-type foundations applying adaptive genetic algorithm (AGA) seeking for the minimal consumption of material in the foundations; this is achieved by minimizing the number of supporting piles and cross-section dimensions of connecting beams. Compromise objective function to be minimized involves the maximum reactive force in piles and maximum bending moment in the connecting beams. Feasibility of a simple weighting technique for the objective function is proved by numerical investigation of objective function domain for several different topologies of foundations. Sizing problem of connecting beams is solved together with the optimization problem. Original finite element program was employed for solution of direct problem. The effectiveness of AGA is shown by optimization of two small-scale grillages possessing up to 17 design parameters. Though the AGA does not yield qualitatively better solutions, it obviously saves the analysis time to obtain the same or even better results due to the faster convergence.
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Keywords: Finite Element Method, Genetic Algorithms, Global Optimization, Optimization of Grillages.



go to top   Numerical and Experimental Investigation of Thermo-Fluid Characteristics of Air Jet Impingement on a Heated Flat Plate Subjected to a Periodic Oscillation
         by W. A. El-Askary , A. Balabel, S. Wilson

         Vol. 6 n. 3, pp. 440-448


Abstract - In the present paper, a novel idea for enhancing the heat transfer characteristics in the impinging process of air jet on a heated flat plate is presented. The heated flat plate is allowed to oscillate periodically in the direction normal to the impinging jet and around the impinging point of the air jet. A Scotch yoke mechanism, which converts the constant rotational motion to a linear motion through a reciprocating mechanism, is used. The shape of the motion of oscillating plate is a pure sine wave over time, which results in a constant rotational speed and consequently a constant wave length of the oscillating linear motion. The numerical simulation of the problem is carried out by solving the Reynolds-Averaging Navier Stokes (RANS) along with the energy equation using the control volume approach on a staggered grid system. The Experimental set up of the problem is constructed and performed in the Thermal Machines Laboratory, Minoufiya University. Preliminary results from both numerical and experimental methods are obtained for the Nusselt number distribution over a fixed flat plate for the purpose of validation. The Nusselt number of the oscillating flat plate is obtained at a defined constant oscillation speed of (ω = 10.476 rad/sec) and compared with that of a fixed flat plate. The comparison showed that an increase of the Nusselt number in case of oscillating the flat plate is attained. This reveals the effect of plate oscillation on the enhancement of the heat transfer characteristics.
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Keywords: Experimental Measurements, Heat Transfer, Impinging Jet, Numerical Simulation, Oscillating Flat Plate, Turbulence Modeling..



go to top   Optimization of Wire EDM Process Parameters of Aluminium Alloy / Flyash / Boron Carbide Hybrid Composites
         by J. Udaya Prakash, J. Milton Peter, T. V. Moorthy

         Vol. 6 n. 3, pp. 449-455


Abstract - The objective of the present investigation is to analyze the influence of Wire Electrical Discharge Machining (WEDM) process parameters like Pulse on time, Pulse off time, Wire feed and Gap voltage on the responses surface roughness (SR) and material removal rate (MRR) during the machining of aluminium alloy (LM 6) flyash boron carbide hybrid composites using Taguchi method. Aluminium alloy (LM 6) was reinforced with flyash particles of 75 µm and boron carbide of 20 µm in 3%, 6% and 9% by weight. Analysis of variance (ANOVA) is done to find the significance of machining parameters which affects the quality characteristics of WEDM process and also to find the relative contribution of machining parameters in controlling the responses of the WEDM process. The parameter with the strongest influence on the response is determined by signal to noise (S/N) ratio response analysis. However, as a final step, confirmation experiment has also been conducted with the optimum combination to predict and verify the improvement of the observed values.
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Keywords: Wire Electrical Discharge Machining, Hybrid Composites, Taguchi Method, Analysis of Variance, Signal to Noise Ratio, Material Removal Rate, Surface Roughness.



go to top   Study On Ability of Palm Oil as Viscosity Index Improvement (VII)  Additive in Thermal Stability (Base Mineral Oil – Cooking Palm Oil)
         by Hasnul Hadi, Liyana Tajul, M.S. Hussin, Z.A. Zailani, M. F. M. A. Hamzas, M.S Bahari

         Vol. 6 n. 3, pp. 456-461


Abstract - This research was conducted to study the thermal stability of cooking palm oil when subjected to heat in an attempt to study its ability as viscosity index improver. Four samples of mixture of Shell Rimula X SAE 40 engine oil and cooking oil at different compositions were heated over a three-hour cooking period, to provide a time course of changes in mixed oil temperature, vapor temperature, and mass of mixed oil. The significant data change of the temperature and mass over time proposes that the thermally stable cooking oil is a suitable viscosity index improver. The effect of heat on mixed oil temperature, vapor temperature, and mass are evaluated to analyze the reliability of cooking oil as Viscosity Index Improvement (VII) based on thermal stability. The Shell Rimula X SAE 40, after being added with fresh cooking palm oil, is expected to exhibit a stable viscosity-temperature curve.
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Keywords: Thermal Stability, Viscosity Index Improvement (VII), Base Mineral Oil – Fresh Oil, Cooking Oil.



go to top   Parameter Optimization For JIS S45C Steel Turning Process Based on Taguchi Method
         by Hasnul Hadi, Liyana Tajul, M. F. M. A. Hamzas, M.S. Hussin, Z. A. Zailani, M. H. M Radzi

         Vol. 6 n. 3, pp. 462-467


Abstract - Modern machining process took the machining tool life span and product quality at highest priority in order to obtained optimum cost effectiveness. In achieving this quality, the consideration of cutting parameters level are the most important part should be engaged. Hence this study investigates the effect of four cutting parameters which are cutting speed, depth of cut, feed rate, and tool nose run off onto JIS S45C steel turning process. The turning process is using uncoated tungsten carbide as cutting tool insert and been computationally simulated using DEFORM software. Three outputs which are cutting load, cutting tool temperature, and tool effective stress will be analyze for this research. The characteristics performance the optimal cutting parameters of the JIS S45C steel turning process is analyzed based on Taguchi method and ANOVA analysis. It is obviously shown us that the feed rate and cutting speed give huge impact on cutting tool temperature change and directly contribute to the tool wear and surface roughness changes. Experimental results are provided to illustrate the effectiveness of this approach. Throughout this study the main cutting parameters that affect the cutting performance in turning operations and the best combination are classified.
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Keywords: JIS S45C Steel, Parameter Optimization, Taguchi Method, ANOVA.



go to top   Tooth Shape Optimization of the Timing Belt with Tangent Grooves Using FEM
         by Weon-Kook Choi,  Young-Doo Kwon, Hyuk-Moon Gil, Kwon-Taek Roh

         Vol. 6 n. 3, pp. 468-478


Abstract - In general, timing gears denote the gears or sprockets installed at the crankshaft that changes a reciprocating motion into a rotary motion, and installed at the camshaft that has the cam to open and shut sucking and exhaust valves. To connect the gear at the crankshaft and the gear at the camshaft, chain, belt, or gear is used depending upon the type of timing system. In the case of long center distance, chain-type or belt-type is often adopted. The belt-type timing system is widely used than the chain-type because of expense and noise. This study analyzed the timing belt and timing sprocket using I-DEAS and MARC that are common commercial packages used in finite element analysis. When an optimal groove in shape and position is formed at the corner position of tooth part in tangent to the body part of a belt, the maximum principal stress arising at the corner decreases a lot, and the endurance of timing belt increases tremendously high.
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Keywords: FEM, Tooth Shape Optimization, Belt System.



go to top   Boiling Heat-Transfer Intensity on Small-Scale Surface
         by Vladimir Yu. Kravets, Olga S. Alekseik

         Vol. 6 n. 3, pp. 479-484


Abstract - Experimental investigations of boiling process on small-scale surfaces with diameters 0.88 mm, 1.73 mm and 4.94 mm were conducted. The boiling process was carried out at atmospheric pressure at the saturation temperature as well as at different subcooling. Water and 96% ethanol as coolants were used. Finally, on the basis of experimental data analysis correlation, which allows determining the boiling heat transfer coefficient as a function of transferred heat flux, the characteristic size of the surface, as well as the thermophysical properties of the coolant was obtained.
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Keywords: Boiling, Heat Flux, Heat-Transfer Intensity, Small-Scale Surface, Subcooling.



go to top   Numerical Simulation of Particle Accumulation at the Membrane Surface in Microfiltration
         by D. Gassara, P.Schmitz, A.Ayadi

         Vol. 6 n. 3, pp. 485-495


Abstract - Numerical simulations of the accumulation of monosized spherical particles at the membrane surface in microfiltration are presented. The model membrane consists of a flat plate of width equal to the diameter of a particle with monosized perforations uniformly distributed along the length of the plate. Then, the study can be carried out on a representative unit element of the model membrane assuming periodic boundary conditions. Particles enter one by one the computation domain and they follow trajectories which take into account hydrodynamic and physico-chemical forces. They can be captured either by the solid wall or by the particles already deposited. The flow in the whole domain is calculated on a heterogeneous permeability field which includes the fluid region (Hele-Shaw region) and the porous region formed by particle accumulation (cake region) using Darcy model. It is recalculated after each particle deposition. Various microstructures of quasi two dimensional cakes are obtained and characterized. They depend on the parameters of the model which are related to the physical parameters such as the ionic strength, the Hamaker constant and the flow magnitude. Results are interpreted quantitatively in terms of variations of the hydraulic permeability of the particle cake backed by the model membrane as a function of the number of particles deposited.
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Keywords: Cake, DLVO, Hydrodynamics, Membrane, Microfiltration, Model, Particle.



go to top   Prediction of Concrete Mechanical Properties by Triphasic Model
         by Aouissi F., Brahma A, Yang C. C.

         Vol. 6 n. 3, pp. 496-500


Abstract - Concrete is a composite material which, in the scale of the microstructure, can be considered as consisting in three phases: the matrix, inclusions and the interface transition zone. The latter has features that reduce the properties of concrete and therefore limits its performances. Indeed, this zone, and by its complex structure, represents the weakest region in the composite. In this study, we use a calculation based on the double inclusion model and the theory of Mori and Tanaka. It has been showed that it is possible to predict the macroscopic behavior of concrete by using an analytical calculation. So, according to the properties and proportions of each constituent phase, the model gives satisfactory predictions on the elastic modulus and compressive strength of concrete. The results were then compared with experimental results.
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Keywords: Interfacial Transition Zone, Elastic Modulus; Compressive Strength, Mechanical Properties Modeling.



go to top   Development of Improved Bottleneck-based Heuristic for Re-entrant Flow Shop with Dominant Machine at M1 and M4
         by M. F. M. A. Hamzas, S.A Bareduan, Liyana Tajul, M.S Hussin, Z.A Zailani, Hasnul Hadi

         Vol. 6 n. 3, pp. 501-506


Abstract - This project investigates the possibility of developing scheduling heuristic using bottleneck approach for a four machine permutation re-entrant flow shop with the process routing of M1,M2,M3,M4,M3,M4 where M1 and M4 have high tendency of being dominant machine. Due to the re-entrant and permutation nature of the process routing, the actual bottlenecks were identified as M1 and combinations of M4+M3+M4 and it utilized two makespan algorithms to identify bottleneck categories. Each algorithm was only valid under several conditions identified as absolute bottleneck conditions. Using these conditions, a new bottleneck based heuristic which called NH is developed and tested using Macro Programming in Microsoft Excel. A total of 3000 simulations were conducted using randomly data in order to evaluate the accuracy of the heuristic. The heuristic performance was evaluated for six and ten job problems. The dominance level groups are divided into levels of weak, medium and strong dominance. For each job problem, the NH results were compared with previously developed absolute bottleneck adjacent matching (ABAM) heuristic. For six job problems, it was shown that the NH performances at medium dominance level are better than ABAM. For ten job problems, the result indicated that NH only produced better result than ABAM at the strong dominance level.
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Keywords: Heuristic, Bottleneck, Scheduling, Re-entrant Flowshop.



go to top   Review on Multiobjective Evolutionary Algorithms and Application in Metal Matrix Composites
         by Iryna Yevseyeva, Vitor Basto-Fernandes, José Grácio

         Vol. 6 n. 3, pp. 507-519


Abstract - This work presents a review on evolutionary algorithms when applied to problems with multiple objectives to be optimized simultaneously. Evolutionary algorithms are well-known optimization techniques utilized in situations where exact methods fail, in particular, in case of optimization of complex, non-convex, non-differentiable, non-smooth and/or discontinuous functions that are common to the real engineering applications, or used for solving combinatorial NP-hard problems, for instance encountered in the search of optimal combination of several parameters. These techniques are shown to be efficient in finding at least sub-optimal solution(s) when solving problems of mentioned complexity. In this work, the recent multiobjective evolutionary algorithms are presented and the potential application of multiobjective evolutionary algorithms in product development is illustrated.
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Keywords: Multiobjective, Optimization, Evolutionary Algorithms, Product Development.



go to top   Numerical Exploration of Endwall Flow in a Slotted Compressor Cascade at Design Condition
         by R. Mdouki, A. Gahmousse

         Vol. 6 n. 3, pp. 520-527


Abstract - With the purpose to enhance aerodynamic performances in highly loaded axial compressor cascades, this work is carried out in order to explore the potential of passive control with slotted bladings in linear cascade configurations under design condition. Based on the optimal slot identified in previous work, the 3D aerodynamic performances of cascade were studied and the influence of slotted blading to control endwall flow was investigated. The calculations are performed on steady RANS solver with standard k-epsilon turbulence model and incompressible regime. The total loss coefficient, turning angle and flow visualizations on the blade and end-wall surfaces are adopted to describe the different configurations. The obtained results show that the slotted blades are not able to control secondary flows near the wall at design condition and so, lose their potential.
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Keywords: Design Condition, High Loading, Endwall Flow, Slotted Blades, Separation.



go to top   Structural Durability of QFN Package Using Three-Point Bending Test
         by M. F. M. Yunoh, S. Abdullah, A. Jalar, M. F. Abdullah and R. Zulkifli

         Vol. 6 n. 3, pp. 528-536


Abstract - This paper presents the effects of stress and applied load on the hardness of an Epoxy Mold Compound (EMC) of a Quad Flat No-Lead (QFN) package. This work was carried out using three-points bending flexural with quasi-static loading test by means of simulation and experiments, three-points bending cyclic test, and nanoindentation technique on an EMC of a QFN package. Five different loads in the range of 30 to 150 N were applied in all tests. All loadings were imposed on the center of the QFN package during the test. A strain gauge was connected to the fatigue data acquisition system that was used for each tested QFN package to determine the response of the captured cyclic strain signal. The nanoindentation a maximum load of 300 mN, was indented at five locations that were perpendicular to the stress line on the EMC of the QFN package after a three-points bending cyclic test was performed. The findings showed that the stress value of the QFN package using simulation and experiment varied with load. The calculated percentage error between the stress of the simulation and the experimental was smaller, which was less than 10%. The constant amplitude pattern of strain signal response was obtained from the cyclic test. This study also indicated a linear relationship between stress and hardness range by means of a coefficient correlation (R2) at 87% and also a linear relationship between strain signal amplitude and hardness range with a coefficient correlation (R2) at 60%. This paper investigates the structure of the QFN package to improve the reliability and the durability of the package when exposed to cyclic bending.
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Keywords: Hardness, Load, QFN, Simulation, Stress.



go to top   Application of HPM- Pade' Technique to a Jeffery–Hamel Flow Problem
         by F. Shakeri, D. D. Ganji, M. Azimi

         Vol. 6 n. 3, pp. 537-540


Abstract - In this paper, the Jeffery–Hamel flow is studied. The velocity is evaluated by using an analytical solution technique: Homotopy perturbation method and Padé approximation. The results compared with the numerical results. Good agreement between analytical approximate solution and numerical method assure us about validity and accuracy of solution.
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Keywords: Jeffery-Hamel Flow, HPH, Pade' Approximation, Nonlinear Ordinary Differential Equations.



go to top   Turbulence Intensity Predictions Using Neural Network Analysis
         by Saad A. Ahmed, Hany El Kadi

         Vol. 6 n. 3, pp. 541-546


Abstract - Interest in using artificial neural networks (ANN) for predicting data has led to a tremendous surge in research activities in the past two decades. Recently, they provide a great deal of promise in the area of thermofluid sciences. Experimental data of the continuous evolution of fluid flow characteristics in a dump combustor is very useful and essential for better and optimum designs of gas turbine combustors and ramjet engines. Unfortunately, experimental techniques such as 2D LDV measurements provide only limited discrete information at given points; especially, for the cases of complex flows such as dump combustor swirling flows. For this type of flows, usual numerical interpolating schemes appear to be unsuitable. Recently, neural networks have emerged as viable means of expanding a finite data set of experimental measurements to enhance better understanding of a particular complex phenomenon. This study showed that artificial neural networks are suitable for the prediction of turbulent swirling flow characteristics in a model dump combustor. These techniques are proposed for optimum designs of dump combustors and ramjet engines.
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Keywords: Swirling Flow, Dump Combustors and Neural Network.



go to top   Asymptotic Stability of a Hardening Elastoplastic Oscillator
         by A. Hammouda, M. Chenia, A. M. Hacene Chaouche, N. Challamel

         Vol. 6 n. 3, pp. 547-552


Abstract - This paper deals the dynamics analysis of a s.d.o.f hardening elastoplastic oscillator, with no external loading, i.e. for free vibration. The hysteretical system is written as an autonomous system with a two dimensional phase space associated with a dimensionless coordinates. The asymptotic stability of the origin point will be shown by solving the evolution problem, for the positive damped system, i.e. a non-linear dynamic system. We will also show the yielding plastic wall analogy for this elastoplastic system.
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Keywords: Elastoplastic Oscillator, Non-Linear Dynamic System, Free Vibration, Single-Degree-of-Freedom, Asymptotic Stability.



go to top   Minimizing of the Flow Velocity in a Micro Channel at Arbitrary Points using FEM
         by Dear Azizi, Diako Azizi

         Vol. 6 n. 3, pp. 553-556


Abstract - Topology optimization of the Navier-Stokes equations is encountered in different branches and applications, such as in the design of ventilation systems for cars and optimal reactors. A common technique applicable to such problems is to let the distribution of porous material vary continuously. For this purpose in this paper, a dynamic model based on Navier-Stokes equations for a Micro Channel (MC) has been investigated and analysed. Moreover, for simulating the performance and characteristics of the MC, dynamic variation of the flow such as its velocity at several boundary conditions has been established. At the next step, the optimization operations will be employed. In this model, the objective is to find the optimal distribution of a porous material in a MC such that the horizontal velocity component at the center of the channel will be minimized.
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Keywords: Dynamic, Equations, Minimization, Simulation, Velocity.



go to top   Cubic Interpolation Profile Method for Transient Hydrodynamics of Solid Particles in Enclosure
         by Nor Azwadi C. Sidik, Mehran Salehi, Adrian Syah

         Vol. 6 n. 3, pp. 557-564


Abstract - The goal of this study is to determine the effect of transient vortex structure on solid particles and explain this behaviour in terms of particles’ trajectories. In the present study, an alternative numerical scheme was proposed to predict the fluid flow and coupled with a Lagrangian scheme on the prediction of solid phase. The dynamics of solid particle in a lid-driven cavity was investigated at a wide range of Reynolds numbers. The results of this study suggest that the particle trajectories are critically dependence on the magnitude of Reynolds numbers and the vortex behaviour in the cavity. Good comparisons with the experimental and previous studies demonstrate the multidisciplinary applications of the present scheme.
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Keywords: Fluid-solid interaction, Cubic interpolation profile, Lid-driven cavity, Solid particle.



go to top   Lattice Boltzmann Numerical Prediction of Fluid Flow in Various Shapes of Shear Driven Cavity
         by Nor Azwadi C. Sidik, Fudhail Abdul Munir

         Vol. 6 n. 3, pp. 565-573


Abstract - Lattice Boltzmann numerical method was employed to simulate an incompressible fluid flow in enclosure. Thorough derivation of macroscopic hydrodynamics equations from the continuous Boltzmann equation is performed. After showing how the formulation of the mesocale particle dynamics fits in to the framework of lattice Boltzmann simulations, numerical results of lid-driven flow inside square and triangular cavities are presented to highlight the applicability of the approach.
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Keywords: Shear driven cavity, lattice Boltzmann method, distribution function, mesoscale method.




International Review of Mechanical Engineering - Papers- Part B

Special Section on Regional Conference on Automotive Research (ReCAR2011)




go to top   A Multi-objective Optimization of Engine Crankshaft Design using modeFRONTIER
         by Rosario Russo, Alberto Clarich, Marco Carriglio

         Vol. 6 n. 3, pp. 574-577

Abstract - This paper shows a multi-objective optimization example in the automotive area using the optimization environment software modeFRONTIER integrated with ANSA as mesh morpher and ABAQUS as structural solver. In the modeFRONTIER environment, the users can easily define a workflow linking together different modules that represent the ‘bricks’ of the optimization problem: design variables, model and mesh files, CAE nodes, specified outputs, as well as optimization objectives and constraints. In particular, several CAE tools can be easily integrated in the process through the available direct interface nodes, allowing the automatic update of parameters and extraction of specified results, until the required optimization objectives are satisfied.  
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Keywords: Multi-objective Optimization, Game Theory, Crankshaft, Modal Analysis, Grid Computing.



go to top   Fatigue Failure Assessment of Variable Amplitude Loading (VAL) on Carbon Steel AISI 1045 using I-kaz Approach
         by M. M. Padzi, S. Abdullah, M. Z. Nuawi, A. Shamsudeen

         Vol. 6 n. 3, pp. 578-582


Abstract - AISI 1045 steel is used extensively by most industry sectors mainly in automotive for applications requiring more strength and wear resistance such as connecting rods. Connecting rods are widely used in variety of car engines. It is subjected to forces generated by mass and fuel combustion, thus, it must be capable to transmitting axial tension and compression. In this paper, connecting rod was used as a research material. This article discusses the analysis on strain signal of fatigued material using a new method called Integrated Kurtosis-based Algorithm for Z-filter (I-kaz) approach. Fatigue tests were performed according to the ASTM E466-96 standard with the attachment of astrain gauge to the tested specimen. Fatigue test was carried out using variable amplitude loading (VAL) at frequency 8 Hz. A data acquisition system was used to collect those fatigue strain signals. Fatigue damage characteristics were observed through the signals and analysis was performed by using I-kaz approach. I-kaz parameter was determined to relate with fatigue failure assessment which will describe the fatigue life.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Fatigue, STFT, Strain, Signal Analysis, Block Loading, VAL.



go to top   Numerical Study of Multiple Channel Road Vehicle Underbody Diffusers
         by B.Daryakenari, S. Abdullah, R. Zulkifli, A. Shamsudeen

         Vol. 6 n. 3, pp. 583-587


Abstract - Since high speed automobiles become common nowadays, reducing the lift coefficient to enhance stability on the road is not just the concern of race cars anymore. Underbody diffusers are one of the well known devices for reducing lift force of the moving vehicle. First, the three dimensional flow over simple car model, namely Ahmed model was simulated. Flow pattern and the results for aerodynamic forces were in good agreement with experimental results. In addition, the same method was utilized to investigate the effect of diffuser and additional splitters on lift and drag coefficients of the models. The popular SST k-ω turbulence model was used to assess aerodynamic forces as well as pressure and velocity distribution. The study provides a good comparison between different amounts of end plates which makes it easier to decide the optimum model.
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Keywords: Aerodynamic, Diffuser, Drag, Lift.



go to top   Electromagnetic Braking System Using Eddy Current for Brake Disc of Al6061 and Al7075
         by M. Z. Baharom, M. Z. Nuawi, G. Priyandoko, S.M. Haris

         Vol. 6 n. 3, pp. 588-594


Abstract - The behaviour of electromagnetic braking using eddy current was studied. Started with preliminary study investigating 3 different materials of aluminium, copper and zinc to choose the best material as brake disc. It also looks on effects of increasing current induced into electromagnet. Aluminium performs better copper and zinc, and then the study continues using two different series of aluminium which are Al6061 and Al7075. A few parameters been varied such as air-gap, brake disc thickness, number of electromagnet turns and voltage supplied to DC motor. For the purpose of recording speed (rpm) and time (s), an optical tachometer connected to PULSE analyzer been used. Graphs presented to show the behaviour and reaction of parameters involved, including the calculation of braking torque that been generated using previous study equation. From this study, it can be concluded that Al6061 have greater performance than Al7075 as the brake disc material. It also founded that the thicker the disc, small air-gap, large number of electromagnet turns and increasing the current induced will increase the performance of this electromagnetic braking. All parameters that been studied show significant effects to be considered in developing electromagnetic braking to replace the conventional braking system.
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Keywords: Eddy Current, Al6061, Al7075, Braking Torque.



go to top   System Modelling and Analysis of the Driveability Response of 4WD Vehicle
         by R.M.R.A.Shah, R. P. Jones, J. S. Pawar

         Vol. 6 n. 3, pp. 595-601


Abstract - This paper presents a system modeling approach for examining the driveability of Four Wheels Drive vehicle. One of key elements to assess the vehicle driveability is to expose the vehicle under harsh driving conditions such as feeding the crankshaft with wide open throttle torque within a short period of time. As a result of this abrupt torque excitation, the vehicle is expected to generate low frequency responses and deliver discomfort feelings induced by resonance effects on sensitive human organs. Understanding the interaction across vehicle component levels is imperative to address the root cause of driveability issues. Frequency migration analysis was carried out to determine the prevailing factors and sub-system components that control this occurrence. Matrices consisting of a range of frequencies have been structured and analysed to precisely pinpoint the sensitivity of vehicle shuffle frequency migration based on different operating modes.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Torsional Model, Driveability, Frequency Migration, System Modeling, 4WD Vehicle, Driveline, Dual Mass Flywheel.



go to top   Elastic-Plastic Analysis of Surface Cracks in Round Bars under Bending Moments
         by A. E Ismail, A. K Ariffin, S. Abdullah, M. J. Ghazali

         Vol. 6 n. 3, pp. 602-606


Abstract - Round solid cylindrical-shaped bars have great important applications in power transmission and cracks normally occur on the surface due to several factors such as corrosions and material defects. Therefore, the failure predictions on the cracked components are a major safety issue. In this work, an elastic-plastic finite element analysis is conducted to investigate the failure behaviour of cracked round bars under bending moments. Different crack aspect ratio, a/b and relative crack depth, a/D are selected ranging between 0.6 to 1.2 and 0.1 to 0.3 respectively. Two strain hardening exponents, n are used, 5 and 10 in order to simulate higher and lower hardening behaviour of the material. The stress/strain material curves are assumed to follow the Ramberg-Osgood relation. During the loading, the J-integral are calculated for several points along the crack fronts, x/h. Then, the limit load of the components are computed according to the reference stress method and it is strongly depend on the a/b, a/D, x/h and n. Subsequently, the developed limit load is validated for its capability to predict the J-integral along the crack fronts. According to the results, the present limit load capable to predict the J-integral under bending moment. However, the predictions are limited within certain crack geometries.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Surface Crack, Limit Load, J-Integral, Reference Stress Approach.



go to top   Study of Correlation between Strain and Structural-Borne Ultrasonic Signals on Automobile Engine
         by M. A. Mohd Sabri, M. Z. Nuawi, A. Ariffin, M. F. Mohd Tahir, S. Abdullah

         Vol. 6 n. 3, pp. 607-610

Abstract - The research work undertaken involved in finding correlation between ultrasonic signals and stress signals through engine block condition monitoring. Ultrasonic sensor is for ultrasonic signals while the strain gauge is for stress signals. Two experiments will be carried out for each of the sensors on the engine block to monitor the inside condition of cylinder block which is the interaction between piston and cylinder block. Type of engine used in this experiment is 4G-15 petrol engines. Two experiments are going on with different devices. The ultrasonic signals and stress signals collected are used for process analysis and be compared to each other by using MatLab software. The analysis methods included time domain analysis, frequency domain analysis, and I-kazTM analysis. The research work concludes with a brief discussion on correlation of two signals and possible of combine these two sensors to develop a more effectively engine condition monitoring method.
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Keywords: Engine Block Condition Monitoring, Signal Processing, Ultrasonic and Stress Signals.



go to top   A Study on Load Dependent Controller Performance for Mechatronic Suspensions
         by Wajdi S. Aboud, Sallehuddin Mohamed Haris

         Vol. 6 n. 3, pp. 611-616

Abstract - The purpose of mechatronic suspensions, or also known as active suspension systems, is to improve ride comfort and road handling. It is proposed that a switching adaptive control scheme be used in an active suspension setup. In the proposed switching control scheme, different controllers are to be activated under different load conditions. In this research, an analytical investigation into the response of a two degree-of-freedom quarter car suspension model, subjected to a bump road disturbance was performed. Both passive and active systems were studied in time domain analysis. The system was simulated under no load, half load and full load sprung mass load conditions. For the active system, different controller gains were used for each sprung mass load. Each of the gains was tuned using LQR and LQG optimization. The performance of the mechatronic suspension showed significant improvements over the passive system. However, the performance of the active suspension controllers, under the respective load conditions for which they were tuned, showed noticeable variations.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: LQR, LQG, Body Acceleration, Tyre Load, Suspension Deflection, Switching Control, Multiple Model Adaptive Control.



go to top   StressBehavior of a Novel Parabolic Spring for Light Duty Vehicle
         by Y.S.Kong, M.Z.Omar, L.B.Chua,S.Abdullah

         Vol. 6 n. 3, pp. 617-620

Abstract - 4x4 pick up is usually designed to be a workhorse where multi leaf spring is the most suitable option for suspension. However, most of the users adopted it for leisure and they demand for better ride and comfort. The driving pleasure and passenger comfort is one of the primary considerations for those pick up wagons. Hence, parabolic spring with the similar characteristics to reduce the weight of the suspension system and provide smooth articulation is designed. In order to maintain the same safety factor as the conventional spring, the strength of the spring must be maintained. This paper presents about kinematic behavior of few types of leaf spring by finite element analysis. The purpose is to find out the maximum stress exerted on the spring while the pickup truck is undergoing several driving conditions. The analysis of different load cases were used to validate the design to prevent catastrophic failure of the design which can cause severe harm to the users. Combination of vertical and windup load cases are being applied in finite element analysis to simulate the parabolic spring behavior. The maximum stress distribution and deformed shape was visualized and analyzed. Stress over the length of the spring was plotted to provide a good visualization of the critical point of high stress region. Besides, the vertical stiffness and windup stiffness of the springs are calculated. To prevent the damages caused by axle wrap, windup stiffness is an important parameter to resist the force generated during this scenario. The stress results show that parabolic spring can provide the same capability in load carrying as multi-leaf spring.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Stress-Strain, Parabolic Spring, Light Duty Vehicle.



go to top   Modelling Brake Torque of CNGDI Engine Using Two-Stage Regression Technique
         by MohdKhair Hassan, Ishak Aris

         Vol. 6 n. 3, pp. 621-624

Abstract - This paper presents the modelling of experimentalresults for compressed natural gas engine with direct injection (CNGDI) engine. The correlation of engine speed, lambda and throttle position in brake torque model was determined using two-stage regression technique. Prior to this investigation, the affecting parameters such as ignition timing and injection timing were identified from the maximum brake torque (MBT) curve at a selected engine speed. The model was then translated into look-up table and uploaded into electronic control unit (ECU) to justify the torque response. The results have shown a good agreement between model and calibration data. Detail results including the verification data and MBT have been presented with discussion. The model can be used as a basis for control strategy design in ECU development which will shorten the calibration process.
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Keywords: CNGDI, Model-Based Calibration, Brake Torque, ECU.



go to top   Development of Ultrasonic Test Rig System for Fuel Injector
         by Y. Istihat, M. Z. Nuawi, A. R. Bahari, W. M. F. W. Mahmood

         Vol. 6 n. 3, pp. 625-629

Abstract - Building a database for a particular system is vital to research and development. Complete and detailed data can be used as a benchmark for the improvement of existing systems. Nowadays trend of researchers to build program software using features of Graphical User Interface (GUI) allows the study to be done by reducing experimental cost depends on reliable simulation process. Focused on the importance of the database, a study to examine the test rig for Fuel Injector system has been developed. An observation by means of Ultrasonic Structure-Borne (USB) takes three parameters such as Pulse Width (ms), Frequency (Hz) and Pressure (bar). These parameters are utilized to obtain a different pattern of USB from the injection of Fuel Injector that uses Compressed Natural Gas (CNG). Data Acquisition System (DAS) that incorporates an Analog to Digital Converter (ADC), ultrasonic sensor, pre-amplifier and laptop computer were used to capture and acquisite the wave data. The results were processed using Matlab® in order to perform statistical analysis. New statistical parameter of I-kaz (Z∞) is introduced to describe the pattern of injections intended to provide a simple explanation.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Ultrasonic, Ultrasonic Structure-Borne, Pulse Width, Statistical Analysis, I-kaz.



go to top   Suppressing Chatter Noise in Windscreen Wiper Operation Using a Robust Hybrid Controller
         by Ali Zolfagharian, Mohd Zarhamdy Md. Zain, Abd Rahim Abu Bakar, Azizan As’arry

         Vol. 6 n. 3, pp. 630-635

Abstract - It has become vital in the modern automotive industry to focus on the noise and vibration suppression of the vehicle sub-systems in order to maintain a competitive advantage. One of the vehicle sub-systems that very often to generate unwanted vibration and annoying noise is a windscreen wiper system. Windscreen wiper system, during its operation, causes a variety of noises such as chatter noise, reverse noise, motor and gear noise. This paper attempts to investigate and suppress chatter noise with frequency range of 50-150 Hz.. In doing so, a robust controller design is proposed and integrated into a two dimensional analytical model of wiper blade system. A hybrid controller is comprised of IS shaping controller an effective feed forward controller and a proportional-integral-derivative (PID) controller. Particle swarm optimization (PSO) is further employed to enhance the capability of traditional techniques for vibration control and noise attenuation of windscreen wiper system.
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Keywords: Wiper Blade, Input Shaping, PID, Particle Swarm Optimization, Chatter Noise.



go to top   Prediction of the Mechanical Properties of Nano-structured Cr-WC Coatings during Electrodeposition Process Using Artificial Neural Network
         by Javad Rajabi, Saeid Nadali, Esmaeil Alibeiki, Jamal Rajabi, Maryam Rajabi

         Vol. 6 n. 3, pp. 636-639

Abstract - In this study using the artificial neural network (ANN), the effects of sodium saccharin and sodium dodecyl sulfate (SDS) additives as well as pulse electroplating parameters such as current density, duty cycle and frequency on the hardness value in Electrodeposition of nano-structured Cr-WC process were modeled. In such as network, the feed-forward multilayer Perceptron was used and trained with back propagation algorithm. The architecture of a neural network consists of 6-10-5-1 model predicted hardness value with 1.88% error in 44 epochs. Comparison between the model predictions and the experimental observations predicted a remarkable agreement between them. Increasing hardness value has been shown by adding SDS and saccharin concentration due to the co-precipitation of WC particle in the coating grain refining effect of saccharin which reduces the grain size of chromium matrix.
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Keywords: Electrodeposition, Artificial Neural Network, Feed-Forward Multilayer, Hardness.



go to top   Study on Correlation of Sound Absorption Coefficient for Automotive Noise Absorption Panel Material by Using Sabine Method and Z-Octave Method
         by M. F. Mat Tahir, M. Z. Nuawi, R. Zulkifli, S. Abdullah, M.A. Mohd Sabri

         Vol. 6 n. 3, pp. 640-643

Abstract - This research aims to develop an alternative way, Z-octave method in order to determine noise absorption coefficient for materials. Noise absorption coefficient, α is one of the parameter to verify material acoustic’s characteristic. Coir fiber was choosen as the material for automotive absorption panel in this study with the experimental run on three different thickness. Reverberation time value was calculated from sabine formula by using the reverberation room method with the help of dBBati-32 measurement and processing software. Then, the coefficients value was carried out for each one third octave frequency begin with 125 Hz until 4000 Hz. Next,for Z-octave method, the raw data captured by the dBBati-32 was transmitted to Matlab and an analysis have been carried out to compute the values. Finally the noise absorption coefficient value from Sabine method, have been evaluated and compared with the value obtained from the Z-octave method to find the correlation between them. From the result, an alternative way to determine noise absorption coeeficient was productively develop. Some of the advantages using the Z-octave method as one of the approach to represent noise absorption coefficient were offering less usage of equipment, time and step to complete comparing with the sabine method.
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Keywords: Z-octave Method, Sabine Method, Noise Absorption Coefficient, α.



go to top   Effect of Fatigue Strain Data Behaviour using Cycle Counting Method
         by Z. M. Nopiaha, A. Lennieb, S. Abdullahc, M. Z. Nuawid, A. Z. Nuryazmine, M. N. Baharin

         Vol. 6 n. 3, pp. 644-648

Abstract - This paper presents fatigue analysis on variable amplitude (VA) loading data using rainflow count and Markov count methods. The objective of this study is to observe the capability of this method in identifying the random behaviour and distribution in a fatigue time series data. For the purpose of this study, a set of case study data consist of nonstationary strain data that exhibits a random behaviour was used. This random data was collected in the unit of microstrain on the lower suspension arm of a car. The collected data was measured for 60 seconds at the sampling rate of 500 Hz, which gave 30,000 discrete data points. In order to compare the result from case study data, the strain signal was selected from the database of Society of Automotive Engineers (SAE) profiles of suspension component, i.e. the SAESUS. The distribution of strain data was then calculated and analysed in the form of rainflow count method, Markov count method and fatigue life assessment and they were then compared. The findings from this study are crucial in the determination of the signal’s pattern behaviour existed in the VA signals.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Fatigue, Variable Amplitude, Rainflow Count, Markov Count, Fatigue Life.



go to top   Mechatronic Drive-Train with Pneumatic Regenerative Braking
         by S.Veera Ragavan, Chin H.C Desmone, Madhavan S.

         Vol. 6 n. 3, pp. 649-653

Abstract - This paper presents modelling, simulation, and implementation of a Pneumatic Parallel Hybrid Regenerative Braking System with Launch Assist (PP-RBS/LA) for Light Motor Vehicles (LMVs). The Hybrid Regenerative Braking System harvests energy during braking. The objective of this work is to design and model an energy harvesting system to regenerate energy that would be otherwise lost as heat during braking and perform a feasibility analysis for implementation of the proposed PP-RBS/LA model on LMVs. This involves harvesting and storing the energy and re-using the captured energy to apply additional torque to the wheels during subsequent acceleration. In addition to energy savings, this system increases energy efficiency and also makes it eco-friendly by reducing the amount of energy required for acceleration and emissions.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Parallel Pneumatic Regenerative Braking System with Launch Assist (PP-RBS/LA), Hybrid Regenerative Braking (HRB), HRB/LA, Pneumatic Parallel Regeneration Model.



go to top   Multiple Pulsating Jets Mechanism for Heat Transfer Enhancement
         by Rozli Zulkifli, Ali Ahmed Gitan, Kamaruzzaman Sopian, Shahrir Abdullah

         Vol. 6 n. 3, pp. 654-658

Abstract - Pulse Jet impingement heat transfer can be used for various applications which requires high convective heat transfer coefficient. The aim of this study is to develop multiple pulsating jet mechanism using a rotating valve pulse jet system. Pulsation of the air jet was produced by a rotating cylinder valve mechanism at frequencies between 10-80 Hz. Multiple pulsating jet mechanism has been developed based on the results of velocity and temperature profile obtained from the single nozzle pulse jet mechanism. Earlier results of the flow structures for a single nozzle pulsating jet mechanism plotted show a distinctive exit air jet profile which can affect the multiple pulsating jet impingement heat transfer characteristics. Dual nozzle pulsating jets have been considered for the new design and the distance between the nozzle and the phase angle are the main parameters that will affect the rate of heat transfer. More nozzles can be added to the system based on the needs of application. A new experimental set-up will be built based on the developed multiple pulsating jet mechanism in order to study the effect of these two main parameters on the cross flow interactions and turbulence intensity of the pulsating jets.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Multiple Pulsating Jets, Jet Impingement, Jet to Jet Distance, Heating and Cooling.



go to top   Experimental Analysis on Engine Performance and Emission Characteristics using Biodiesel obtained from Non-edible Oil
         by A. M. Liaquat, H.H. Masjuki, M. A. Kalam, M. Varman, M. A. Hazrat

         Vol. 6 n. 3, pp. 659-665

Abstract - There are concerns that biodiesel feedstock may compete with food supply in the long term, if the raw materials are vegetable virgin oils only. Therefore, throughout the world, large amounts of non-edible oil plants are available in nature. In this paper, experimental study has been carried out to analyze engine performance and emission characteristics for direct injection diesel engine using biodiesel obtained from non-edible oil such as jatropha oil and was blended with diesel fuel (DF) by 5% (JB5), 10% (JB10), 15% (JB15) and 20% (JB20) volumetrically without any engine modifications. Due to the presence of molecular oxygen, biodiesel undergoes improved combustion in the engine and has less polluting emissions in comparison with normal diesel fuels. Engine performance test was performed at 100% load keeping throttle 100% wide open with variable speeds of 1500 to 2400 rpm at an interval of 100 rpm. Whereas, emission tests were carried out at 2300 rpm at 100% and 80% throttle position. As results of investigations, there has been a decrease in torque and brake power, while increase in specific fuel consumption (sfc) has been observed for all biodiesel blend fuels over the entire speed range compared to DF. In case of engine exhaust gas emissions, reduction in HC, CO and CO2 were found for all blends. Besides, sound level for blend fuels was also reduced compared to DF. It can be concluded that jatropha biodiesel blend fuels can be used in diesel engines without any engine modifications and have beneficial effects both in terms of emission reductions and alternative petroleum diesel fuel.
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Engine Performance, Emission, Jatropha Biodiesel, Non-edible Oil.



go to top   Signal Analysis Software as an Educational Tool for Engine Diagnostic System
         by N. K. Khamis, M. Z. Nuawi, S. Abdullah, Z. M. Nopiah, L. Abdullah

         Vol. 6 n. 3, pp. 666-670

Abstract - This paper shows a signal analysis software that had been used as an educational tool to provide students a better understanding in diagnostic method for automotive engine using statistical signal analysis. This software can provides basic hands-on knowledge and experience that can be used in experimental and laboratory based projects. Within this paper the application of signal analysis was introduced by using Integrated Kurtosis-Based Algorithm for Z-Notch Filter (I-kaz™), other derivatives method of I-kaz™ and Mesokurtosis Zonal Neoparametric (M-Z-N) method. Basically, this software can be used in various studies on the automotive component such as monitoring condition of the operating machines in the automotive engine.  
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Statistical Signal Analysis, I-kazTM Method, M-Z-N Method, Engine Monitoring.



go to top   Development of UKM Solar Car “TUAH” for Shell Eco-Marathon Asia 2011
         by A. Ariffin, M. F. Mat Tahir, M.A. Mohd Sabri, S. Abdullah, A. Shamsudeen

         Vol. 6 n. 3, pp. 671-674

Abstract - This paper presents the development of the UKM solar cars named Tuah. Various numbers of solar race events organized around the world has propelled the continuous development of solar cars by different research teams and Shell Eco-Marathon Asia was one of them. The aim of the competition was to develop Asia’s most fuel-efficient cars built by the students. The vital aspects in designing a superior solar car are lightness and their aerodynamic behavior. The purpose for reducing the drag coefficient CD, especially in designing the shape of the car and material selection for car body are some of the crucial task to optimize the solar car performance. UKM car had choose an eye drop figure as the key design feature for aerodynamically and aesthetic intention. Composite reinforced with carbon fiber had been selected for the car body material because of its superior strength while given the lightest weight to produce the optimize selection combination. Both of these features will be discuss more on this paper.  
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Design, Car Body, Shell Eco-Marathon, Aerodynamic, Drag Coefficient.



go to top   Development of a Computational Fluid Dynamics Model for Direct Injection Hydrogen Fueled Engine
         by Khalid I. Hamada, M.M. Rahman, A. Rashid A. Aziz

         Vol. 6 n. 3, pp. 675-679

Abstract - Development of a computation fluid dynamics (CFD) model for a direct injection into the combustion chamber of the hydrogen-fuelled engine was presented. An integrated subroutine is developed to simulate the hydrogen-injection process in a gaseous state. The reacting flow and accompanied physical phenomena were numerically analyzed utilizing the KIVA code based on multidimensional fluid mechanic theory. The developed model was successfully executed for low and high engine speed under lean mixture condition. Patterns of the flow field combined with the history of hydrogen concentration inside the combustion chamber during the injection phase were utilized for evaluating the performance of the hydrogen injection process. The identical distribution for the hydrogen concentration was observed. As well, the vectors of the flow field seem to have a bigger size and coarser distribution in case of the high engine speed (5000 rpm), especially near to the piston face. The developed model can be extended for further optimization process.  
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: CFD, KIVA, Hydrogen Fuel, Direct Injection, Reacting Flow.



go to top   Deformation Response of Steel Sheet Metal under Transverse Impact Loading
         by S.S. Arsad, S. N. S. S. Noh, A. Ayob, Z. Ahmad, A. Abdul-Latif, N. Kamsah, M. N. Tamin

         Vol. 6 n. 3, pp. 680-684

Abstract - Steel sheet metals used as body panels and trims of an automobile are often subjected to lateral loading. In the event of a crash, the panel will likely experience impact loads in the range where strain-rate effects are significant. This study examines deformation response of the sheet metal subjected to transverse impact loading using combined finite element (FE) method and drop weight impact test. Johnson-Cook constitutive model parameters for the 0.045C (wt. %) cold-rolled steel used are extracted from tensile test data of the sheet metal specimens at straining rates ranging from 0.001/sec to 0.1/sec. Results show that the calculated amount of plastic work or energy of 78 % is dissipated within the short dynamic plastic deformation process of 0.001 sec. Predicted dynamic response of the sheet metal compares well with measured data.  
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Johnson-Cook Model, Transverse Load, Impact Test, High Strain Rate, Plastic Work.



go to top   Inverse Power Law Model for Extrapolation of Fatigue Life Curves
         by E. A. Azrulhisham, D. A. Wahab, S. Abdullah, N. Nikabdullah, C. H. Che Haron

         Vol. 6 n. 3, pp. 685-690

Abstract - In view of increasing pressures of shortened development cycles and desire to save costs, inverse power law scaling has been devised for operative life estimation based on accelerated laboratory test data extrapolation. Derived from the Coffin-Manson’s model of fatigue life, this analytical solution however is not capable in addressing probabilistic nature of fatigue. This paper is aimed to provide further insight into the operative life estimation based on parametric models derived from integration of inverse power law stress-life model and probabilistic fatigue life distributions. Maximum likelihood estimation is applied in deriving the parameters of the parametric models and the probabilistic fatigue life curves are obtained from reliability function of accelerated laboratory test data. PSN and PεN curves at operative life as well as any life region can be estimated based on inverse power law acceleration factors. The procedures presented in this study can be applied in estimating the probabilistic fatigue life curves at an accelerated pace resulting in shortened development cycles.  
Copyright © 2012 Praise Worthy Prize S.r.l. - All rights reserved


Keywords: Inverse Power Law, Operative Life Estimation, Maximum Likelihood Estimation, Probabilistic Fatigue Life Curves.


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