摘要
基于三维流-固耦合有限元动力学仿真分析模型和直接耦合算法,分析了一种锥形节流阀在入口流速脉冲激励下由关闭状态开启而后重新关闭全过程的流量特性、压差特性及阀门开度的高频波动等非线性动力学响应特性,并采用小波分析方法等对阀门开度响应等进行了时-频域分析。选择不同的流体-结构模型的数值积分方法组合及时间步长对流-固耦合动力学求解算法进行了实际应用检验;然后对阀芯质量、弹簧参数与油液参数等系统参数以及激励速度幅值与脉宽等激励参数对其工作过程动力学响应的影响进行了细致的数值分析比较。结果表明:流体模型积分算法的选择对流-固耦合计算结果的影响较大;对该阀而言,阀芯质量与油液体积弹性模量的改变对阀芯振动频率的影响较为显著,油液粘度的改变对阀门开启的滞后量及振动相位的影响较大,而弹簧刚度及预紧力的改变对阀门的最大稳定开度的影响较大;阀芯与阀座间的碰撞使阀芯的振动频率提高。
Based on a 3-D fluid-structure interaction dynamics model and direct coupling solving method, the nonlinear dynamic response characteristics, such as variable flow rate, pressure difference and valve opening, of a conical orifice valve are numerically simulated to show its whole working process of opening and closing under inlet fluid velocity pulse excitation. Especially, the high-frequency fluctuation characteristics of valve opening are investigated in details. The wavelet analysis method for short unstationary process data is employed to analyze the time-frequency spectrum of the valve opening response. Practical verification of the solution algorithms is performed using different time-integration methods and time steps. Then, a series of numerical experiments are conducted to compare the effects of each change of several system parameters, such as valve core mass, spring parameters and hydraulic oil parameters, width. The numerical experiment results and excitation parameters, such as inlet show that the different fluid integration fluid velocity amplitude and ulse algorithms influence the solution results quite much; the influences of change in valve core mass or fluid compressibility on the valve opening oscillation frequency are significant; oil viscosity change leads to oscillation phase difference; different spring stiffnesses and preloads change the maximum valve opening; the initial collisions between valve core and seat result in increase of the valve opening oscillation frequency.
出处
《工程力学》
EI
CSCD
北大核心
2017年第9期239-247,共9页
Engineering Mechanics
基金
国家973项目
关键词
流-固耦合动力学
三维有限元仿真分析
直接耦合算法
锥形节流阀
时变高频非线性振动
参数影响规律
fluid-structure interaction dynamics
3-D finite orifice valve
time-dependent high-frequency parameters element analysis
direct coupling method
conical nonlinear vibration
effects of changes in key parameters