NUMERICAL STUDY OF THE FLOW BEHAVIOR IN THE UNIFORM VELOCITY ENTRY FLOW PROBLEM

A numerical investigation is presented to study the behavior of lamina r flow in the developing zone of a channel from very law to high Reyno lds numbers. In this regard, the full Navier-Stokes equations are solv ed using a control-volume-based finite element method with dual defini tions for the momentum components at integration points in order to su ppress the decoupling problem. The investigation shows that there is a peculiar overshoot behavior in the region whose limiting solution req uires substantial mesh refinement. This behavior begins in the vicinit y of the wall that affects wall shear stress calculations and, consequ ently, pressure drop computations. The study shows that the domain sol ution approaches limiting values with appropriate mesh refinement. The solutions for low Reynolds-number flows also approach limiting soluti ons as the Reynolds number is decreased.