Direct Numerical Simulation of Transonic Wake Propagation in the Presence of an Adverse Pressure Gradient and Streamline Curvature

Abstract

ow and turbulent structure of the wake. The ability to understand how pressure gradients and streamline curvature aects the structure of the wake is essential to predicting how the wake will aect the performance of the application in which it is found. The transonic ow regime is becoming of more interest as gas speeds in turbomachinery increase. A direct numerical simulation of transonic wake ow being shed by a cambered airfoil in the presence of adverse pressure gradients and streamline curvature is presented here. It was observed that the turbulence characteristics arising from the cambered airfoil that generated the wake dominate the evolution of the wake for dierent distances downstream depending on the component of the Reynolds stresses that is being considered. These characteristics dissipated the most quickly in the shear stresses and endured the longest in the tangential normal stresses. Curvature was observed to have limited inuence on the evolution of the streamwise normal stresses and an extensive impact on the tangential normal stresses. The transport equation of the shear stresses indicated that the large asymmetry observed in those shear stresses was largely contributed to by the diusion term in collaboration with the production term.