Experimental Method to Find the Flux and Temperature Distribution on the Flat Receiver of Small Central Receiver System

Abstract

The central receiver concept for solar energy concentration and collection is based on a field of sun-tracking mirrors (heliostats) that reflect the incident sunshine to a receiver (boiler) at the top of a centrally located tower. A solar central receiver system is used for medium temperature process heating applications or in solar thermal power plants. A flat receiver plate was experimentally investigated with a small scale solar central receiver system in order to study the effects of receiver temperature and flux distribution on the receiver plate. Flux density distribution at the focal region of the concentrator can be estimated, if the temperature on the focal region is measured. In the present work, a thermocouple method is used to estimate the flux density distribution on the flat receiver plate. The variation of temperature on the receiver plate is experimentally estimated by varying the number of heliostats that are focused on the receiver plate.  It is seen that for all cases of heliostat numbers, the radiation reflected from the heliostat field on the receiver surface generates a variation of flux density distribution. The peak flux is obtained at a single point on the receiver surface. For the small central receiver system of 7 heliostats, the peak flux value is found around 4110 W/m2 (± 2%) and the average value of flux of the receiver plate is 1984 W/m2(± 2%).
Copyright © 2017 Praise Worthy Prize - All rights reserved.