Optimization of Design and Process Parameters for Maximized and Stable Solar Receiver Efficiency
Maintenance of stable process conditions and optimal solar thermal reactor efficiency demand direct response to transient behavior of solar radiation. This study presents a thermodynamic model including an explicit correlation between the feedstock flow rate and receiver aperture size to achieve optimal receiver efficiency under stable process conditions. Optical analysis of the system was made using TracePro software package yielding an optical model with absolute deviation for peak flux and half width of 7.6 W/m2 and 0.375 mm respectively. Two different types of receiver aperture mechanisms were designed and manufactured to experimentally test the impact of aperture size, and the impact of different design concepts. The first one features translational motion, whereas the other concept uses a rotational disc mechanism. An experimental proof of both concepts has been studied using a 7 kW high flux solar simulator using these two variable aperture mechanisms. The TracePro model was used to determine the aperture opening factor (AOF) for both mechanisms, which was used to develop the thermodynamic model. In this model, maximum
achievable reactor temperatures were observed for iris and rotary aperture and found to be 251°C and 325°C
respectively, at 135 A of solar simulator input current. Optimum aperture size and optimum flow rate were
identified for desired steady state reactor temperature at different flux levels.