Near-field radiative heat transfer in the three-body system made of nanoporous silicon carbide

Near-field radiative heat transfer between two nanoporous silicon carbide (SiC) can be remarkably enhanced by inserting an intermediate body with finite thickness. The heat flux of the proposed system is enhanced significantly comparing with that of the two-body counterpart, because the intermediate body which behaves like a midrepeater can assist the transfer of the surface phonon polaritons (SPhPs) and hyperbolic phonon polaritons (HPPs). Both the filling fraction of air in the nanoporous SiC and the thickness of the intermediate body play important roles to the radiative heat flux. The heat flux experiences a first increase and then decrease process for the fixed filling fraction as the thickness of the intermediate body increases, and it can reach a maximum value. The maximum heat flux shifts toward larger thickness of intermediate body when the filling fraction increases. The dependence of heat flux on filling fraction is also studied in detail. The results obtained in this work provide an efficient way to further enhance the near-field radiative heat transfer. Graphical abstract (a) The heat fluxes of the three-body system and the corresponding two-body counterpart as a function of the vacuum gaps. The thickness of the body 2 is $$\delta = 30$$ δ = 30 nm and the filling fractions for both three-body and two-body systems are fixed at $$f = 0.3$$ f = 0.3 . It is seen that the heat flux in the three-body system enhanced remarkably compared with its two-body counterpart. (b) The dependence of heat fluxes on vacuum gaps $$d_{1}$$ d 1 and $$d_{2}$$ d 2 for different filling fractions. The heat flux can be modulated by filling fraction.