Effects of local geometry and boundary condition variations on transpiration cooling

The influences of the thermal conductivity and porosity of the porous wall and locally extraordinarily high heat fluxes on the hot surface and the location of a low porosity region within one and two layer porous walls on the temperature field were analyzed numerically. The local thermal non-equilibrium model was used to predict the temperature distributions in the solid and phases within a 2-D computational domain. The predicted results show that the porosity and thermal conductivity of the top layer significantly influence the temperature distribution of the solid matrix when the hot surface is subjected to uniform or locally extraordinarily high heat flux boundary conditions. In addition, the study shows that the location of the low porosity region also significantly affects the temperature field in the two layer model consisting of a bronze matrix and a ceramic coating.