Study on jet simulation of high pressure nozzle

ZHANG Zhen， ZHANG Qiao-fang
（School of Mechanical Engineering， Zhejiang University of Technology， Hangzhou 310014， China）

Abstract： Aiming at the problem of high pressure jet flow speed diverge fast and speed unsteability，the numerical simulation tool of Fluent was applied to the analysis of high pressure jet flow. According to the high pressure nozzle structure characteristics，axisymmetrical geometric models of nozzle and external injection area were established. Grids were divided and encrypted according to fluid velocity changes in the injection process. The submerged and nonsubmerged jet flow of high pressure nozzle and jet flow with different contraction angles were simulated. Velocity distribution was extracted on the basis of fluid theory and the results were analyzed. The results indicate that different constraction angles have a great influence on the aix speed，the speed gets the best speed steability. Additional，the speed of nonsubmerged jet flow is more concentrative compared with the submerged jet flow. The simulation results can be used as the basis for the selection of the high pressure nozzle structure and spray pattern.
Key words： high pressure nozzle； Fluent； jet simulation； submerged； nonsubmerged； contraction angle