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采用粒子图像测速仪(PIV)对圆管内横向蒸汽射流凝结速度场进行了测量.垂直圆管直径80 mm,喷嘴直径3.2 mm,喷嘴与管道壁面垂直,蒸汽射流雷诺数20192＜Res＜543763,动量通量比为25＜J＜400,过冷水温度为30＜Tw ＜60℃.通过射流中心轨迹线,揭示了射流动量通量比、射流雷诺数和过冷水温度对速度场的影响规律.射流中心轨迹可用指数形式的曲线拟合,引入射流动量通量比J和射流雷诺数Res,得到中心轨迹线预测关联式,预测值在实验测量值30％以内.“,”The velocity field characteristics of steam jet condensation in crossflow of water in pipes were investigated by using Particle Image Velocimetry (PIV) measurement technique.The diameters of the vertical pipe and the nozzle were 80 mm and 3.2 mm.The angle between the pipe wall and the nozzle centerline was 90°.The subcooled water temperature was in the range of 30～60 ℃.The Reynolds number of the steam jet was in the range of 20192～543763.The jet momentum ratio was in the range of 25～400.According to the contours of the velocity fields and streamlines,the influences of jet momentum ratio,jet Reynolds number and water temperature on the jet flow field were explored.The jet centerline trajectory equations in exponential form were established based on the local maximum mean velocity.By introducing the jet Reynolds number Res and jet momentum ratio J,the correlation for prediction of jet centerline trajectory equations was proposed,and the predicted results were within 30 ％ of the experimental data.