Near-field thermal radiation in a cavity

Abstract

The near-field radiative heat fluxes in the cavity are numerically investigated in this work. The cavity in this study is formed by surrounding the two doped silicon slabs with the boundary materials. The geometric feature of the cavity in this paper is characterized by the dimensionless distance between the doped silicon slabs. First, the near-field radiative heat fluxes between two isolated doped silicon square slabs are numerically investigated and the edge effects on the near-field radiative heat flux between two isolated doped silicon slabs are illustrated. Then the near-field radiative heat flux exchange in the cavity is computed according to the dimensionless distance. The effects of the material type and temperature of the cavity boundary on the radiative heat fluxes are studied. The radiative heat fluxes between the isolated doped silicon slabs without the boundary are diminished as the increment of the dimensionless distance. Contrarily, the radiative heat fluxes between the doped silicon slabs in the cavity can be impressively enhanced as the increment of the dimensionless distance. By using the appropriate dimensionless distance and boundary material, the radiative heat flux in the cavity can be modified to approximate or exceed the radiative heat flux between two semi-infinite doped silicon slabs. This work can be applied to the thermal management in the nanoscale.