Here we propose a forced air circulation system to reduce the convective heat loss across the aperture of a dish concentrator. The function of the proposed system was validated with computational fluid dynamics (CFD) simulations. Compared to a concentrator without such a system, the modified solar dish cavity receiver could clearly reduce the convective heat loss and its fluctuation in the receiver. In the best case studied, the convective heat losses could be suppressed by up to 58%. In addition, two types of air circulation modes (clockwise and anticlockwise) were compared, showing that the anticlockwise mode yields better performance.