Numerical Research on Minimum Radius of Two-phase Water Jet

Owing to dynamic property of water jet in the air,it makes difficult to predict the shape and performance of water jet accurately.The criteria judging the water jet contractive section is presented and numerical solutions of two-phase unsteady flow are solved for multi operating-points free-flow jet.And then the energy and vorticity distributions of water jet are analyzed,especially for the interface of two-phase flow.According to the predictive results of the free surface of water jet with VOF method,important parameters including contractive radius and expansion rate of water jet are obtained and the scale effect of free-flow jet is also discussed in the paper.