中文摘要：

提出将中心体喷嘴与异形喷嘴组合以产生更好的空化射流效果的思路。采用Mixture多相流模型，在15MPa的射流压力下，对正方形出口、三角形出口和圆形出口3种中心体喷嘴产生的淹没射流流场进行数值计算，重点对轴向速度、径向速度、湍动能和空泡相体积份额进行了对比分析。研究表明：圆形出口的中心体喷嘴比另两种异形出口的中心体喷嘴产生更高的射流速度和湍动能；正方形出口比三角形出口的中心体喷嘴的射流稳定性能更强，圆形出口的中心体喷嘴产生的集束性能较强；异形出口的中心体喷嘴产生的流场中，空泡相延伸距离更长，异形出口的中心体喷嘴产生的空化射流效果更好。

英文摘要：

Combination of central-body nozzle and abnormal nozzle is presented to further improve cavitation jet performance. Under the jet pressure of 15MPa, three submerged jets were produced with square, triangle and circular outlet sections respectively. Those flows were numerically simulated through employing Mixture Mu!tiphase Model. Axial and radial velocities,turbulence kinetic energy, volume fraction of cavitation zone were obtained thereby and analyzed comparatively. The study shows that adop- tion of circular-outlet central-body nozzle results in the highest axial jet velocity and turbulence kinetic energy. Square-outlet central-body nozzles are proved to be able to generate more steady jet flows than triangle-outlet central-body nozzles while circularoutlet central-body nozzles have more concentrated jet flows. Axial extension distances of cavitation zone in jet flow discharged from the abnormal-outlet central-body nozzles are longer than that in the circular jet ,which indicates the abnormal-outlet central- body nozzles is more helpful in improving cavitation jet performance.