Numerical study of effects of geometric parameters on the flow and cavitation characteristics inside conical nozzle of autonomous underwater vehicles

The geometric parameters (ratio of orifice's length to diameter, conical angle, and inner-wall roughness) of conical nozzle are investigated via computational fluid dynamic method to reveal the effect on the flow and cavitation characteristics. The variation of geometric parameters affects the distribution of the static pressure and the drag force, which in turn affects the mass flow rate at the outlet. The results indicate that the conical angle plays a dominant role in effecting the flow and cavitation characteristics. The higher the intensity of cavitation, the more notable the effect of geometric parameters on cavitation characteristics.