Boundary-layer resistances of artificial leaves in turbulent air: I. Leaves parallel to the mean flow

Boundary-layer resistance to heat transfer from plates was studied in a wind tunnel which produced turbulence with streamwise intensity in the range 3.5 to 25% and a longitudinal integral scale of the streamwise turbulence component (Lu,x) in the range from 8 to 100 mm. It was found that heat transfer enhancement occurred due to the turbulence, and that at any given intensity, this enhancement was determined by the ratio of Lu,x to the characteristic dimension of the plate.