Analysis of Thermal-Fluid-Structure Coupling and Resonance Forecast for Link Butterfly Valve Under Small Opening

When the link butterfly valve operates at a small opening degree in high temperature working conditions,it is prone to the problem that the valve is stuck,the strength is insufficient and the butterfly plate is violently vibrating.This paper shows simulation experiments of both thermal-fluid-structure coupling and resonance forecast about DN600 link butterfly valve in the working conditions of 250℃ and 0.5 MPa by ANSYS software.The medium is mixed with compressed air and flue gas.Flow field characteristics of the valve and stress deformation,modal and flow-induced vibration of butterfly plate are analyzed when the valve opening is less than 30%.The results indicate that,when the valve opening is less than 30%,fluid flow is relatively smooth in front of butterfly plate,a large number of vortexes are found behind the butterfly plate,and fluid flow is greatly chaotic in this position.The equivalent maximum stress and deformation of butterfly plate are relatively large when the valve locates in openings between 10% and 30%; the intensity of the butterfly plate is enough; the axial deformation does not impact opening and closing of the valve.The butterfly plate is likely resonant when the valve opening is less than 10%.The research of this paper provides a crucial reference for flow field characteristics of link butterfly valve,an analysis of intensity and rigidity of butterfly plate,and a resonance forecast of butterfly plate when the valve works in small opening.     

动态流量平衡阀启闭过程中的线弹性不等值力

为了解决动态流量平衡阀流量控制精度无法达到要求的问题,建立了动态流量平衡阀动力学模型以及阀芯运动方程,数值模拟了相同口径和不同口径平衡阀阀芯处于不同位移下的三维流场模型,对比试验与数值模拟的阀芯位移误差和压差位移流量特性曲线,获得了线弹性不等值力变化规律,确定了不等值力修正系数,并优化了开孔型线.研究结果表明:通过引入线弹性不等值力修正系数,优化阀芯可变开孔后,减小了阀芯实际位移与理论位移间的误差,使试验与数值模拟的流量特性曲线趋于一致,并使流量控制精度满足5%的误差要求.      

船用流量平衡阀声学性能仿真预测研究

应用Solidworks软件对某型船用流量平衡阀流道结构进行优化设计,首先将几何模型导入Fluent软件中进行压力场和速度场仿真分析计算,获取改进后的阀体三维模型。进一步利用Ansys软件和声学分析软件LMS预测了流量平衡阀在不同工作压差和阀芯位移下流道的噪声和振动特性曲线,分析结果表明:阀体噪声和振动随着工作压差和阀芯位移的增加而变大。本文对于冷水系统各类阀件减振降噪设计具有一定的指导意义。     

截止阀波纹管的结构参数对其应力影响分析

选取特定工况下截止阀波纹管建立有限元模型,在有限元结构分析基础上研究波纹管在相同压力载荷和轴向位移载荷下结构尺寸的变化对应力分布的影响规律。研究表明,波纹管在压力载荷和轴向位移载荷下,结构尺寸对应力分布影响较大,并且在不同工况下结构尺寸对波纹管应力分布影响不同,相同载荷下波纹管的不同位置应力分布不同。