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为了预测空化初生，用特征线法计算了减速运动活塞前管内一维非定常流的压力变化及分布，分析了管内压力变化规律及空化初生的条件。作为对照观察了液体中作减速运动活塞表面的空化现象，发现活塞在导管中做减速运动时，其表面压力下降。活塞前水柱愈长，活塞表面压力愈低。撞击骤停的活塞体基本上按线性变化的加速度减速，加速度变化斜率愈大，活塞表面在停止时所达到的压力愈低，加速度变化斜率趋于无穷时，该压力趋于确定的极限值。提出使用测量液体中运动物体的加速度来预测空化初生，以便监测装置运行。
In order to predict the initial cavitation, the pressure variation and distribution of one-dimensional unsteady flow in the front tube of the decelerating piston were calculated by the characteristic line method. The variation of pressure in the tube and the conditions of cavitation were analyzed. As a control, the phenomenon of cavitation on the surface of the piston for deceleration was observed. It was found that when the piston decelerated in the catheter, the surface pressure dropped. The longer the water column before the piston, the lower the pressure on the piston surface. The piston body striking and stopping basically decelerates according to the linearly changing acceleration. The larger the slope of the acceleration change, the lower the pressure reached by the piston surface when it stops and the slope of the acceleration tends to infinity, and the pressure approaches a certain limit value. It is proposed to predict the cavitation at birth by measuring the acceleration of moving objects in the liquid in order to monitor the operation of the device.