射流泵流动特性的PIV试验研究OA
PIV experimental study on flow characteristics of a jet pump
为深入探究射流泵内部复杂流动机理,基于高精度粒子图像测速(PIV)系统,对射流泵内部有限空间射流流场进行二维可视化测量与定量分析,重点研究了面积比m与流量比q对其流动特性的调控机制.结果表明,流核区长度随q减小而缩短,m越小,缩短速率越快;轴心速度在吸入室内先加速、后衰减,而衰减速率与q负相关;回流区的高度和宽度与q负相关,与m正相关,当m=4,q=0.534时,回流区无量纲高度和宽度分别为0.26与0.73,当q降至0.04时,高度增加到0.6,而宽度则大幅增加至4.37;射流半宽随轴向距离先增加后稳定,q则影响中游半宽分布;流动中上游速度分布呈现部分自模化状态,下游呈现管流特性;径向速度呈反对称分布,速度峰值随q减小降低,速度方向的转变影响射流的加速和衰减;喉管入口为压力最低点,q对喉管和扩散管内沿程压力的上升幅度具有显著影响;瞬态流场出现射流边界波动、尾迹振荡及流核间断等复杂流动结构;展向涡在喷嘴出口生成并沿剪切层分布,q的减小加剧涡对流核区的侵蚀,促进湍流融合与涡量耗散.研究结果为射流泵的优化设计提供可靠的试验依据.
To deeply investigate the complex flow mechanisms inside a jet pump,2D visual measurement and quantitative analysis of the confined space jet flow field inside the jet pump were carried out based on a high-precision particle image velocimetry(PIV)system.The study focused on the regulatory mechanisms of the area ratio m and the flow rate ratio q on its flow characteristics.The results indicate that the length of the potential core decreases as q decreases,and the smaller the m,the faster the shortening rate.The axial velocity accelerates first and then decays within the suction chamber,and the decay rate is negatively correlated with q.The height and width of the recirculation zone are negatively correlated with q and positively correlated with m.When m=4 and q=0.534,the dimensionless height and width of the recirculation zone are 0.26 and 0.73,respectively;when q drops to 0.04,the height increases to 0.6,while the width increases significantly to 4.37.The jet half-width first increases with axial distance and then stabilizes,with q influencing the half-width distribution in the midstream.The velocity distribution in the midstream and upstream exhibits a partial self-similarity state,while the downstream displays pipe flow characteristics.The radial velocity shows an antisymmetric distribution,with the peak velocity decreasing as q decreases;the change in velocity direction affects the acceleration and deceleration of the jet.The throat inlet is the point of minimum pressure,and q has a significant influence on the magnitude of the pressure rise along the throat and diffuser.Complex flow structures such as jet boundary fluctuations,wake oscillations,and potential core intermittency appear in the transient flow field.Spanwise vortices are generated at the nozzle exit and distributed along the shear layer;a decrease in q intensifies the erosion of the vortex core region,promoting turbulent mixing and vorticity dissipation.The results of this study provide a reliable experimental basis for the optimal design of jet pumps.
王乐;梁蕴致;姚伍平;李红钢;莫小瑜;龙新平
武汉大学 动力与机械学院,武汉 430072||水射流理论与新技术湖北省重点实验室,武汉 430072武汉大学 动力与机械学院,武汉 430072||水射流理论与新技术湖北省重点实验室,武汉 430072武汉第二船舶设计研究所,武汉 430064武汉第二船舶设计研究所,武汉 430064武汉大学 动力与机械学院,武汉 430072||水射流理论与新技术湖北省重点实验室,武汉 430072武汉大学 动力与机械学院,武汉 430072||水射流理论与新技术湖北省重点实验室,武汉 430072
机械制造
射流泵粒子图像测速(PIV)流动特性面积比流量比
jet pumpparticle image velocimetry(PIV)flow characteristicsarea ratioflow rate ratio
《流体机械》 2026 (2)
1-9,9
国家自然科学基金项目(U2430205)
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