Unsteady numerical simulation of flow over square prism with control plate

Unsteady flow in high Reynolds number over a square prism with control plate (a small flat plate was set upstream of the square prism) is numerically investigated, where RNG turbulence model, SIMPLE algorithm and dual time-stepping method are combined to solve. The simulation results indicate that the produced vortex is suppressed or Karman vortex is generated according to the distance varying between the control plate and prism, which influences the boundary layer of prism separation in three different flow patterns. The time-averaged drag coefficient decreases steeply. When the control plate deviates the prism coaxial, the time-averaged lift coefficient increases drastically. The jump phenomenon is observed with the increasing deviation of the control plate as that the drag coefficient increases and lift coefficient decreases abruptly after that the drag reaches to the minimum value and the lift coefficient reaches to the maximum value respectively.