Experimental Evaluation of the Solar Flux Distribution on the Flat Receiver of a Model Heliostat System

Abstract

For the efficient utilization of solar energy, its concentration is required. Central Receiver systems have higher concentration ratio as compared to other concentrated solar power techniques. The solar flux density distribution and the temperature on the receiver plate are important parameters in assessing the net thermal energy, in predicting the performance of solar concentrator and in the design of solar receiver. Here the flux distribution on the flat receiver of the ganged type model heliostat system consisting of nine heliostats has been evaluated by using the thermocouple method which is the indirect method of flux measurement. The variation of the solar flux density distribution on the receiver plate have been estimated for the different numbers of heliostat by using the energy balance equation. For this model heliostat system the peak flux and average flux values are estimated to be 3950.57 (± 3%) W/m² and 1798.77 (± 3%) W/m² respectively. This analysis will be useful for sizing of the receiver. For the average flux value on the receiver plate the receiver size for the nine heliostats system will be 0.3m x 0.3m with the intercept factor of 64%.The average optical concentration ratio was 5.6 with the optical efficiency of the system 0.50 ± 3 % during the test period.