Experimental Investigations on the Velocity and Temperature Distribution on a Flat Plate Placed Horizontally in a Uniform Stream and Heated from Below

Abstract

For the purpose of presenting information to the flow in the atmosphere near the earth's surface, experimental investigations of turbulent boundary layer on a horizontal flat plate placed in a uniform stream and heated from below have been conducted using JMA wind-tunnel. Simultaneous 22 observations of the mean velocity and the mean temperature in the boundary layer have been obtained for the ranges 1.8m/s∞<13m/s and 15 deg<ΔT<90deg. Results :-within these ranges, the distributions of velocity and temperature in the middle portion of turbulent boundary layer are nearly logarithmic. Similarity between the velocity and the thermal fields in the entire region of the boundary layer was, however, not found. These profiles are, on the other hand, also well represented by power law formulas. The Richardson number of the flow field in the above mentioned portion of the layer is found to be nearly proportional to the height z from a wall.