Instability of wall jet produced by two-dimensional inclined jet

This paper focuses on a two-dimensional jet that impinges on a sloping wall surface. It investigates the vibration behavior and wall jet development morphology during wall impingement. Flow visualization experiments of jets impinging on a plate arranged vertically and at an angle of 65° were conducted. In the range where the distance between the jet nozzle and the plate is from the near field to the transition region, the vibration form of the impinging jet changes sensitively. The range of the distance between the jet nozzle and the impinged plate where no shear vortex forms on the wall surface is expanded by the inclined impinging jet. On the upward side, where the fluid easily flows due to the inclined impinging jet, an increase in the vibration frequency was also confirmed as the wall jet velocity increased. PIV measurements showed that wall jet separation after inclined impinging was delayed in comparison with vertical impinging, and a stable wall jet was formed.