Laminar and Turbulent Boundary Layers on Moving, Nonisothermal Continuous Flat Surfaces

Abstract

The heat-transfer characteristics of buoyancy-affected laminar and turbulent boundary layers on nonisothermal continuous flat surfaces that move steadily through a quiescent ambient fluid are studied analytically. Both cooling and heating of the continuous plate which is moving upward or downward in a horizontal, vertical, or inclined direction are considered. A mixing length model for the eddy diffusivities of momentum and heat based on an extension of the Van Driest model is employed in the turbulent boundary layers. Numerical results, such as wall shear stress, surface heat-transfer rate, and surface temperature variation, are presented for various Reynolds and Grashof numbers for fluids with a Prandtl number of 0.7, for both laminar and turbulent boundary layers. A good agreement is found between the analytical and experimental results for friction factor in turbulent boundary layer over an isothermal, continuous moving plate.