ABSTRACT
External forced convection take place when a flow moves over the external surface of a solid body and forms hydrodynamic and thermal boundary layers around the surface. There are two well-known methods to solve external boundary-layer flow and heat transfer problems. One is the similarity method to obtain the exact solution. The chapter outlines the equations that can be used to calculate boundary-layer thickness, shear stress, and the friction factor for a given Reynolds number; as well as heat flux, the heat transfer coefficient, and Nusselt number for a given Reynolds number and Prandtl number. The other powerful method to solve boundary-layer flow and the heat transfer problem is using the integral approximate solution. Instead of performing mass, momentum, and energy balance through a differential fluid element inside the boundary layer as the similarity method, the integral method performs conservation of mass, momentum, and energy across the boundary-layer thickness at a given differential x-direction.
