文丘里管渐缩段影响限流性能试验与仿真

Experimental and Simulation Study on the Performance Under the Influence of Venturi Tube Tapered Section

为研究3种渐缩段结构形式对限流文丘里管内部流场状态及限流性能的影响,对3种不同渐缩段的文丘里管在正常补水以及临界工况下的流体性能进行试验,研究其压损与限流特性;并基于ANSYS Workbench,对试验工况进行数值模拟。结果表明,出口压强计算值与试验值误差分别为2.0%,0.5%,0.5%,与试验结果吻合良好。模拟结果表明,压损系数与文丘里类型相关,与管道流场速度无关;渐缩段为弧形弯曲两次形状的压损性能优于渐缩段弧形弯曲一次形状,压损值约为弯曲一次形状的90%;渐缩段为传统直线型的压强性能最差。在临界工况下,3种文丘里管因产生空化均能较好地表现限流作用,但两次弧形平滑过渡的渐缩段形式因其结构均匀对管道内空化反应更有利,限流作用更好。

In order to study the influence of three types of tapered sections on the internal flow field state and current limiting performance of the current limiting Venturi tube,a test has been made of the fluid performance of three different tapered sections of the Venturi tube under normal water make-up and critical conditions to study their pressure loss and current limiting characteristics.In addition,based on ANSYS Workbench,a numerical simulation is carried out of the test conditions.The results show that the errors between the calculated outlet pressure and the test value are 2.0%,0.5%and 0.5%respectively,which are in good consistent with the test results.The simulation results show that the pressure loss coefficient is related to the type of Venturi while independent of the velocity of the pipe flow field.The pressure loss performance of the tapered section is better than that of the tapered section,which is curved twice,with a pressure loss value of approximately 90%of the curved once shape.The tapered section,which is of the traditional linear type,is characterized with the worst pressure performance.Under critical conditions,the three kinds of Venturi tubes can better perform the current limiting effect due to cavitation,but the tapered section with two smooth arc transitions is more favorable for cavitation reaction in the pipeline due to its uniform structure,which makes the current limiting effect much improved.