Critical and optimal thicknesses of thermal insulation in radiative–convective heat transfer

Heat transfer through a thermal insulation layer in radiative-convective heat transfer on its nonconcave surface is considered. Combinations of determining parameters at which the heat flux passing through this layer reaches an extremal absolute value (a maximum corresponds to a critical thickness of thermal insulation, and, a minimum, to an optimal). The qualitative analysis of the dependence of the heat flux on the determining parameters makes it possible to choose the thermal characteristics of the insulation and its thickness, providing the desired reduction in the intensity of heat transfer through the insulation with a nonconcave surface of double curvature in conditions of radiative-convective heat transfer.