Convection From a Rectangular Plate - People | MIT CSAIL
The complication is that the value of h depends on temperatures, fluid-velocity, and the area, shape, orientation, and roughness of the plate surface. A value of h for a 1 m by 1 m plate will usually be larger (and never smaller) than h for a 2 m by 2 m plate under otherwise identical conditions. The larger plate will transfer more heat because it has four times the area of the smaller plate ...