Thermal Analysis of a Solar Cavity Receiver

Design of solar thermal cavity receivers has been a subject of interest for the renewable energy community. The ability to harvest solar energy through fluid-thermal interactions, not only provides a viable, efficient, and environmentally friendly source of power, but also one which reduces the cost of implementing and generating the power needs of today.;The following investigation develops a simulation of the thermal and heat transfer behavior of a solar cavity receiver. The model constructed treats the convective and radiative exchange as the main component to energy capture of solar energy within the system.;The results show that tightly packed cavity receivers exhibit higher working fluid temperatures for both laminar and turbulent conditions in comparison to medium and loosely packed cavity receivers. Tightly packed cavity receivers demonstrate net heat transfer distributions with local maxima, with highest net heat transfer in the middle of the cavity receiver, in comparison to loosely packed systems, which have decreasing linear-like net heat transfer distributions with increasing fractional cavity receiver depth for both laminar and turbulent flow conditions.;It is demonstrated that further increasing the aperture size of the cavity receiver beyond 60 cm, results in lower working fluid temperatures and net heat transfer distributions for varying aperture size for both laminar and turbulent conditions. It was demonstrated that decreasing helical pipe size of the cavity receiver results in higher working fluid temperatures and net heat transfer rates for both laminar and turbulent conditions.;It was based on these observations and conclusions that an optimal cavity receiver design was investigated for three popular heat transfer fluids. A tightly packed cavity receiver with minimized aperture and helical pipe diameters was chosen as the optimal cavity receiver for the three popular heat transfer fluids.