It is necessary to take all the details into account: material of the walls and its design in your storage container and what is the curvature of screen plate. Wall design and material shall be such as to promote good dissipation of heat while the curvature of screen should be as smooth as possible. I know some Chinese ppl use  3 or 5-layer corrugated cardboard  moistening all the time by dripping down water and located outside container.