Abstract
Flow over an oscillating thin flat plate is solved with the implicit virtual boundary method in the present study. This method can not only solve the immersed boundary problem for a zero thickness flat plate accurately but also use a patch grid to reduce the calculating time and keep the accuracy at the same time. Furthermore, this method does neither assume the plate as rectangular geometries with thin thickness nor rebuild grid system with moving boundary when plate is rotating. Due to the successful simulation in this case, ideas different from the past can be gained. After solving the problem successfully, the entrance pressure may be got to predict how the drag varies with the angle of plate, Renold number, distance between two plates and angle velocity of vibration.