摘要
应用热膜流速仪对圆形断面自由湍动纯水射流的流场进行精细量测后,得出射流的卷吸流量和卷吸后总流量沿程增大的变化规律,当出口雷诺数大于某个临界值时,流量增大系数与雷诺数及断面距离无关,基本上是一个常数;当雷诺数小于临界值时则随雷诺数变化。初步探讨了大涡卷吸的机理,卷吸流量与卷吸涡特性的关系,卷吸流速系数性质及其与雷诺数的关系。
Detailed measurement by hot-film anemometer on the flow field of turbulent round water jets was carried out.The rule of variation of the entrainment discharge for the jet is obtained. The influence of the exit Reynolds number on the entrainment is found.The mechanism of entrainment has been investigated preliminarily:a relationship between the entrainment discharge and the properties of the entrainment vortex is given,and the effect of the exit Reynolds number on the coefficient of entrainment Yelocity is found also.
基金
国家自然科学基金