Study of the effective parameters on the performance of a micro thermophotovoltaic system with micro porous combustion chamber

The advantage of micro thermophotovoltaic systems is the direct conversion of heat energy into electrical energy without any moving parts. For an adequate performance of thermophotovoltaic systems, uniform and high temperature along the micro-chamber wall is required. In the present study, a laminar premixed combustion of hydrogen-air in a micro porous chamber is studied. Non-equilibrium thermal condition between gas and solid phases and radiative transport equation in solid phase is considered . Using numerical simulation, the effect of several parameters on the radiation efficiency of thermophotovoltaic system including equivalence ratio, porosity, porous thermal conductivity and inlet mixture velocity have been studied. The results show that increasing the equivalence ratio up to 1 increases the wall temperature and increasing the thermal conductivity of the porous medium, results in a more uniform temperature distribution. Also decreasing the inlet velocity, porosity and thermal conductivity of the porous medium increases the system's radiation efficiency. The convection heat transfer between the gas and solid phases inside the porous and the radiation and conduction heat transfer in the porous for the porosity of 0.4 and 0.8 were compared and it was shown that the role of radiation heat transfer inside the porous is negligible.