Optical performance maintenance of solar dish collector system under service loads based on tracking compensation and receiver translational compensation methods

Solar dish collector system are inevitably subjected to wind load leading to structural deformation, which will deteriorate its flux distribution and optical performance, how to realize the optical performance maintenance is particularly important. The methods of tracking compensation and receiver translational compensation are proposed for realizing the optical performance maintenance of dish collector systems (includes horn-cavity receiver for Stirling heat engine and cylindrical cavity receiver) under the combined action of self-weight and wind loads, and the maintenance effect is evaluated in detail using a large solar dish/Stirling system with 17.7 0 m diameter constructed by authors as a case study. Furthermore, the optical-thermal performance of a cylindrical cavity receiver before and after compensation is also comparatively analyzed. The results show that both compensation methods can significantly eliminate the unfavorable problems of local high flux, non-uniform circumferential energy distribution and optical intercept loss under service load, and the optical/thermal performance is very close to the ideal optical condition, which achieves excellent maintenance effect. Using the two compensation methods, the energy distribution maintenance factor Ee of the cylindrical cavity receiver is significantly reduced from 0.12 to 0.17 to 0.01–0.06; for the horn-cavity receiver, the Ee is reduced from 0.41 to 0.62 to 0.04–0.19, and the maximum energy difference within the four-quadrant region is reduced from 27.83 kW to only 4.86 kW at most unfavorable 45°–180° condition, which can effectively guarantee the safe and smooth operation of the Stirling heat engine.