This study details the numerical modelling and optimization of natural convection heat suppression in a
solar cavity receiver with plate fins. The use of plate fins attached to the inner aperture surface is presented
as a possible low cost means of suppressing natural convection heat loss in a cavity receiver. In the
first part of the study a three-dimensional numerical model that captures the heat transfer and flow
processes in the cavity receiver is analyzed, and the possibilities of optimization were then established.
The model is laminar in the range of Rayleigh number, inclination angle, plate height and thickness
considered. In the second part of the study, the geometric parameters considered were optimized using
optimization programme with search algorithm. The results indicate that significant reduction on the
natural convection heat loss can be achieved from cavity receivers by using plate fins, and an optimal
plate fins configuration exit for minimal natural convection heat loss for a given range of Rayleigh
number. Reduction of up to a maximum of 20% at 0 receiver inclination was observed. The results
obtained provide a novel approach for improving design of cavity receiver for optimal performance.