Numerical determination of heat transfer and pressure drop characteristics for converging-diverging flow channel

A finite difference scheme was utilized to predict periodic fully developed heat transfer and fluid flow characteristics in a converging-diverging flow channel. The basis of the method is an algebraic non-orthogonal coordinate transformation which maps the complex fluid domain onto a rectangle. This transformation avoids the task of numerically generating boundary-fitted coordinates. Its adaptation to a periodic example problem of converging-diverging flow channel is illustrated. Representative results were carried out for laminar flow, Prandtl number of 0.7, in the Reynolds number range from 90 to 1635, for various taper angles of converging-diverging flow channel, and for three ratios of maximum-minimum height of the flow channel. Moderate enhancement in the Nusselt number results occurred, at higher values of Reynolds number for most cases, when compared with the corresponding values for a straight duct.