Thermal analysis on void cavity of heat pipe receiver in advanced solar dynamic system

In this paper, unit heat pipe receiver in advanced solar dynamic system was numerically simulated. Accordingly, mathematical model was set up, numerical calculation method was offered, the temperature field of Phase Change Material (PCM) was shown, the performance of void cavity was analyzed, numerical results were compared with the experimental results concerned. Calculation results show that PCM (close to Canister's side) melts earlier and proceeds inward during sunlight periods, thermal resistance of void cavity is much bigger than that of canister's side wall. Canister's side wall has a great effect on heat transfer of PCM canister. During eclipse periods, the temperature distribution of canister reduces gradually from centre to outside. The thermal storage ability of PCM canister decreases because of void cavity. Void cavity influences the process of phase change. The temperature gradient of PCM zone is very significant because of void cavity. So the thermal stress of heat pipe receiver may increase, and the life of advanced solar dynamic system may decrease.