前混合水射流喷嘴流场的数值模拟

Numerical simulation of nozzle flow field of premixed water jet

为了获得前混合水射流喷嘴内外流场的流动特性,利用Fluent软件对喷嘴内外流场进行数值模拟。根据射流特性,数值模拟中湍流模型选用标准k-ε模型,液固两相流动采用欧拉模型,分析不同喷丸压力下水流场和弹丸流场最大轴向动压强和最大轴向速度的变化规律以及外流场中不同靶距对流场轴向速度的影响。结果表明:在内流场,喷嘴出口处流场最大轴向动压强和最大轴向速度随着喷丸压力的增加而增大,且同一喷丸压力条件下水流场最大轴向动压强小于弹丸流场最大轴向动压强,水流场最大轴向速度大于弹丸流场最大轴向速度;在外流场,水流场和弹丸流场最大轴向速度随着靶距的增加而减小。

This paper is motivated by the need for obtaining the flow characteristics of the inner and outer flow field of the former mixed water jet nozzle,using the Fluent software to perform the numerical simulation the inner and outer flow field of the nozzle. The study building on the characteristics of jet involves the numerical simulation of turbulence model using standard k-ε model,liquid-solid two-phase flow using the Euler model; an analysis of the variation of maximum axial dynamic pressure and maximum axial velocity in the water and projectile flow field under different shot peening pressure; and an analysis of the influence of different target distance on the axial velocity of the flow field in the external flow field.The results show that along with an increase in shot peening pressure comes an increase in the inner flow field,flow field at the nozzle exit maximum axial dynamic pressure and the maximum axial velocity; and given the same shot peening pressure,water flow field has a smaller maximum axial dynamic pressure than projectile flow maximum axial dynamic pressure and a greater maximum axial velocity than the maximum axial velocity in flow field of projectile; in the outflow field,the increase inthe target distance is followed by a decrease in the maximum axial velocity of the flow field and the velocity of the projectile.