Delayed Detached Eddy Simulation of Flow Over an Airfoil with Synthetic Jet Control

Abstract

Delayed Detached-Eddy Simulation (DDES) is a hybrid Reynolds-Averaged Navier Stokes/Large Eddy Simulation (RANS/LES) model similar to Detached-Eddy Simulation (DES) but with some modifications to reduce the influences of ambiguous grid densities in the numerical results. This model was implemented in CDP, a parallel unstructured grid incompressible flow solver, developed at the Center for
Integrated Turbulence Simulations (CITS) at Stanford University. CDP has the advantage of being nearly energy conserving. Several simulations and validations of static cases in a modified NACA 4415 were performed. Implementation/validation of two different synthetic jet models (detail and Reynolds stress based) are presented. The detail model resolved the synthetic jet dynamics in time while the Reynolds stress model tries to capture the major effects that the synthetic jet induces in the flow. The Reynoldsstress
synthetic jet model is based on experimental Particle Image Velocimeter (PIV) data and also on numerical data from the detail model. Numerical results show the effects of the actuators on the vortical structure of the flow, as well as on the aerodynamic properties.