An experimental study on turbulent characteristics of an impinging split-triplet injector

This paper presents turbulent characteristics of an impinging F-O-O-F type injector in which fuel and oxidizer impinge on each other to atomize under the different momentum ratio. Water was used as an inert simulant liquid instead of fuel and oxidizer. The droplet size and velocity in the impinging spray flow field were measured using a PDPA. The gradient of the spray half-width(b₂) along the long-axis direction declined throughout the entire spray flow field with increasing the momentum ratio from 1.19 to 6.48. However, the gradient of the half-width(b₁) along the short-axis direction decreased with increasing the momentum ratio. The turbulence intensity and turbulent kinetic energy were converged into the center of the initial region with increasing the momentum ratio. As the momentum ratio increased from MR = 1.19 to MR = 6. 48, the turbulent shear stress decreased. The results of this study can be used for the design of an impinging type injector for liquid rockets.