Balancing Otto Engines

Florian Ion T. Petrescu(1*), Victoria Relly(2)

(1) Senior Lecturer at UPB (Bucharest Polytechnic University), TMR (Theory of Mechanisms and Robots) department, Romania
(2) Senior Lecturer at UPB (Bucharest Polytechnic University), TTL (Transport, Traffic and Logistics) department, Romania
(*) Corresponding author

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Internal combustion engines in-line (whether working in four-stroke or two-stroke engines-Otto, Diesel, and Lenoir) are generally the most used. Their balancing problem is extremely important for their proper functioning. There are two possible types of balancing: static and dynamic. Total static balancing make that the sum of the forces of inertia of a mechanism be zero. There are also and a partial static balancing. Dynamic balancing means to canceling all the moments (loads) of the inertial of the mechanism. One mode of design of an in line engine, is the one with the gap between cranks of 180 [deg], or 120 [deg]. Another type of motor construction is the engine with opposed cylinders in line, called cylinder "boxers". In this type of engine (regardless of their position, which is most often vertical) for two-cylinder motor, one has a total static balancing and a dynamic imbalance. Similar to the model of masses concentrated in rotary motion, are solved and the balancing of the rotating shafts. An important way to reduce losses of heat engines is how to achieve a balanced best.
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Internal Combustion Engines; Two Stroke Engines; Four Stroke Engines; Static Balancing; Dynamic Balancing; Forces of Inertia; Moments of Inertia

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