颗粒在气固两相圆湍射流近场截面对气相的影响

Particle effect on the gas phase in a near field cross section in gas-solid round turbulent jets

为探讨气固两相射流中不同粒径颗粒对气相的作用,用激光粒子动态分析仪(PDA)测量气固两相圆湍射流中X/D=5截面上的气相流动参数,并与相同出口速度的单相射流做比较。喷口直径为20mm,气相出口Re=13600。采用了从50μm到300μm之间6种不同平均粒径的玻璃微珠作为颗粒相。结果表明:粒径较小的粒子对气相轴向时均速度沿径向衰减的延迟作用较强,对气相轴向和径向湍流度的削弱幅度较大。粒径较大的粒子能增强轴心附近气相轴向湍流度。

Experimental investigations of particle-laden two-phase round jets at the X/D = 5 cross section were used to investigate the particle effect on the gas phase. The gas-phase turbulence parameters were measured with a partieal dynamic analyzer （PDA） and compared with these in a single phase jet. Six different size particle from 50 μm to 300 μm were used as the solid phase. The jet Reynolds number based on the nozzle exit gas velocity and nozzle diameter was 13 600. The nozzle diameter was 20 mm. The results show that small particles strongly flatten the gas-phase velocity attenuation process in the radial direction, and more strongly reduce the radial and axial turbulent intensities than the larger particles. The large particles enhance the axial turbulent intensity near the jet axis.