Effect of selective coating on the top heat loss characteristics of trapezoidal cavity: a computational approach

In the present work the effect of selective coating on the top heat loss characteristics of a trapezoidal cavity has been presented. Selective coatings are multi-layered coatings which enhances absorption of radiation on a surface while inhibiting emission from it. In the present study selective coating is applied on the bottom absorber plate of the trapezoidal cavity. Computational domain of the trapezoidal cavity is developed and analysed. Finite Volume Method (FVM) is employed to calculate natural convection in the domain, radiation from the bottom absorber plate to glass cover, wind induced forced convection on the glass cover and radiation from glass cover to ambient. Parametric study has been carried out by varying the input heat flux, the absorptivity of the selective coating and emissivity of the selective coating. (paper)