Chapter 2 - Mixed convection boundary-layer flow along a vertical flat plate

Abstract

Mixed convection flows, or combined forced and free convection flows arise in many transport processes in engineering devices and in nature. These flows are characterized by the buoyancy parameter λ = Gr/Ren, where Re is the Reynolds number, Gr is the Grashof number, and n (> 0) is a constant that depends on the flow configuration and the surface heating conditions. The parameter λ provides a measure of the influence of the free convection in comparison with that of forced convection on the fluid flow. Buoyancy forces can enhance the surface heat transfer rate when they assist the forced flow, and vice versa. Buoyancy forces also play a significant role in the incipience of flow instabilities and they are responsible for either delaying or speeding up the transition from laminar to turbulent flow. This chapter presents three-dimensional mixed convection boundary-layer flows, which arise where buoyancy introduces significant cross-flow into an otherwise two-dimensional flow, or in three-dimensional flow configuration to which there is complementary buoyancy driven flow.