Numerical simulation and experimental research on oscillation performance of disc-type jet oscillator

Abstract

Based on active flow control technology, the two wall jets attached to a standard cylindrical surface due to the Coanda effect will output a detached jet when they collide. The direction of the output jets produced by this collision is very sensitive to small changes in the two wall jets. Therefore, a new type of curved-wall supersonic compressible disc-type jet oscillator is proposed by using the oscillating feedback jet as the source of wall separation. Through monitoring the internal flow field, the jet core’s pressure attenuation, the jet’s amplitude, and the wall pressure are analyzed. The results show that the disc-type jet oscillator model with a double-bend inlet has the best performance. After adding a multi-pipe outlet structure to the model, the oscillators with various disc diameters were simulated at different inlet pressures and air inlet frequencies to the wall-off control port. The oscillation performance of the disc jet oscillator is better when the diameter of the disc is 32 mm and 20 mm, and the included angle between the wall-off control port and the horizontal direction is 45°. Two kinds of oscillators of the same diameter as the model are experimentally studied, and the results prove the feasibility of the disc-type jet oscillator.