NUMERICAL INVESTIGATION OF TURBULENT FLUID FLOW AND HEAT TRANSFER CHARACTERISTICS IN A STREAMWISE‐PERIODIC CORRUGATED DUCT WITH CONSTANT CROSS‐SECTIONAL AREA

Abstract

Turbulent fully developed periodic heat transfer and fluid flow characteristics in corrugated two‐dimensional ducts with constant cross‐sectional area are numerically investigated. The governing equations are solved numerically by a finite‐volume method for elliptic flows in complex geometries using collocated variables and Cartesian velocity components. Two different turbulence models (the second moment closure and the k—ε) for approximation of the Reynolds stresses are applied. The performance of the models were assessed by comparing the results with experimental data. The results show the advantages of the stress closure model compared to the k—ε model. The overall Nusselt number and the pressure drop ratio results are obtained for the boundary condition of a uniform wall temperature for two inclination angles ø and two duct aspect ratios (H/L) and for Reynolds number ranging from around 3000 to 35,000. The overall Nusselt number predicted by the k—ε model is upto 25% higher than the values predicted by the second moment closure. The plots of the velocity vectors show a complex flow pattern. The mechanisms of heat transfer are explained by the flow phenomena separation, deflection, recirculation, and reattachment.