Characteristics and Application to Manufacturing Technique of Spiral Jets

1.1998-1999年的研究内容：(1)制作了7种喷嘴对螺旋射流流体特性的影响；(2)测量了各喷嘴喷出的速度分布和静压分布，研究了射流特性；(3)对锥形喷嘴喷出的旋转射流进行了流动显示和速度测量，研究了射流特性。结果表明：(1)当射流从锥形喷嘴喷出时，随着锥角的增大，喷嘴出口轴线上的静压增大；随着锥角的增大，下游静压迅速下降，压力梯度变陡。(2)锥形喷嘴喷出时，流体在喷嘴出口附近加速，其加速程度随锥角的增大而增大。(3)锥形喷嘴喷出旋流时，射流宽度随锥角的增大而变宽。(4)锥形喷嘴喷出旋流时，雷诺应力随着锥角的增大而增大，湍流扩散也随着锥角的增大而变得更加明显。

1. Contents of research made in 1998-1999(1)Nozzles of seven types affected to fluid characteristics of spiral jet have been made.(2)The distributions of velocity and static pressure Issuing from each nozzle are measured and jet characteristics are investigated.(3)In case of swirling jet issuing from taper nozzle, flow visualization and velocity measurement have been carried out and jet characteristics have been Investigated.2. Results obtained In 1998-1999(1)In case of the jet issuing from taper nozzle, static pressure on the nozzle axis at the nozzle exit becomes higher with an increase of taper angle. Downstream static pressure falls down rapidly and pressure gradient becomes steeper with an increase of taper angle.(2)In case of the jet Issuing from taper nozzle, the fluid is accelerated near the nozzle exit and its degree of acceleration becomes larger with an increase of taper angle.(3)In case of the jet with swirl issuing from taper nozzle, jet width becomes wider with an increase of taper angle.(4)In case of the jet with swirl issuing from tapered nozzle, Reynolds stress becomes larger with an Increase of taper angle and accordingly the turbulent diffusion becomes more marked with an increase of taper angle.