弯管中的气液两相流水击现象

以 90°弯管为研究对象 ,对气液两相流水击压力波在弯管中的传播和衰减规律进行了实验研究 .实验弯管采用曲率半径与管径比R /d分别为 1.9,2 .5 ,3.2 ,3.8;含气率范围为 0～ 1.7% ;表观液速为 0 .2 3～ 1.6 4m/s .得出了弯管中内外两侧不同部位水击压力及其随含气率、流速变化的规律 .压力波在弯管中的传播与在直管中差异很大 ,弯管外侧压力明显大于内侧 ,在弯管出口与入口直管段处两侧压力相同 ,形成压力环 .压力环形状受含气率影响最大、表观液速次之、曲率半径影响最小 .经过弯管后水击压力有不同程度的衰减 .随着气含率的增加 ,压力衰减加快

Water hammer phenomena in the gas-water two-phase flow through angle pipe

Right angle pipeline being taken an example, the propagation and attenuation law of the water hammer pressure wave of the gas-water two-phase flow in angle pipe is studied by experiments. The ratios of the curvature radius to the inner diameter of the tested angle pipes are 1.9, 2.5, 3.2 and 3.8 separately. The void fraction of the tested two-phase flow media is in the range of 0～1.7%, and the superficial velocity of it is 0.23～1.64 m/s. The water hammer pressures in the inner side and the outer side of the angle pipe and the variation laws of them with the void fraction and the superficial velocity are obtained. It is shown that, the water hammer pressure in the outer side is greater than that in the inner side, at the exit and the entrance of the angle pipe, the pressure in the outer side is the same as that in the inner side, and therefore, a pressure "ring" is formed. The influence of the void fraction on the shape of the pressure "ring" is the greatest, the superficial velocity's is secondary, and the curvature radius' is the least. The water hammer pressure attenuates after the angle pipe. The rate of the attenuation increases with the increase of the void fraction.