A numerical simulation of heat transfer in an enclosure with a nonlinear heat source

Two-dimensional simulations of natural convection driven by the absorption of nonuniform concentrated solar radiation in a molten binary salt-filled enclosure inclined at 0 ≤ ϕ ≤ 60 are presented. The enclosure is volumetrically heated from the top boundary and accommodates a black rigid, heat-conducting plate of finite thickness at the lower boundary, which aids in the generation of natural convective mixing at the lower boundary. The governing equations that account for the depth-dependent absorption of radiation are solved using the finite-element method. Numerical results reveal that increasing the inclination angles decreases the natural convection and higher Rayleigh promotes natural convection.