Turbulent heat transfer analysis of silicon carbide ceramic foam as a solar volumetric receiver

A local non-thermal equilibrium heat transfer analysis was conducted for an investigation of the heat transfer performance of silicon carbide ceramic foam as a possible volumetric solar receiver. Turbulent heat transfer takes place from the receiver solid phase to the air as it passes through the porous receiver. Radiative heat transfer was coupled with conduction and turbulent convection using the P1 model which describes radiative heat transfer in optically thick media reasonably well. The two energy equations written in one-dimensional form for the air and foam were combined with the irradiation transport equation based on the P1 model. Analytic solutions are obtained for the developments of air and ceramic temperatures as well as the pressure along the flow direction derived under the low Mach approximation. The solutions serve as a useful tool for designing a novel volumetric solar receiver of silicon carbide ceramic foam.