文丘里定风量阀的阀芯绕流阻力系数研究
Study on the Spool Turbulence Resistance Coefficient of Venturi Constant Air Volume Valve

在设计文丘里阀时，计算阀芯所受到的绕流阻力大小是确定阀芯所在位置的关键步骤，但利用现有公式进行文丘里阀阀芯绕流阻力计算时，绕流阻力系数变化较大，不利于绕流阻力的计算。所以本文针该问题，提出了可以通过改变绕流阻力计算公式中速度取速点以及部分阀芯几何参数的方法，以维持绕流阻力系数的稳定。并利用ANSYS软件建立了三维阀体仿真数值模拟模型，并进行了不同开口大小和不同结构参数下的绕流阻力系数对比分析。同时，搭建了风洞实验平台，进行了数值模拟模型的对比试验，验证了仿真模型的准确性。研究结果表明，随着取得流体速度的位置越靠近最窄通流面积而趋于稳定，且在最窄通流面后0~2 mm计算出的绕流阻力系数最为平稳，同时改变阀芯的几何参数，同样会影响绕流阻力系数的稳定性。
In the design of the Venturi valve, calculating the winding resistance of the spool is the key step to determine the position of the spool, but when the existing formula is used to calculate the winding resistance of the Venturi valve spool, the winding resistance coefficient changes greatly, which is not conducive to the calculation of the winding resistance. Therefore, in this article, a method is pro-posed to maintain the stability of the winding resistance coefficient by changing the velocity point and some spool geometric parameters in the calculation formula of winding resistance. The three-dimensional valve body simulation numerical simulation model was established by ANSYS software, and the comparison and analysis of the flow resistance coefficient under different opening sizes and different structural parameters were carried out. At the same time, a wind tunnel exper-imental platform was built, and a comparative test of the numerical simulation model was carried out to verify the accuracy of the simulation model. The results show that the fluid velocity tends to be stable as the position is closer to the narrowest flow area, and the flow around the resistance co-efficient calculated 0~2 mm after the narrowest flow surface is the most stable, and changing the geometric parameters of the valve core also affects the stability of the flow resistance coefficient.