作者简介:廖云龙(1985—),男,硕士,高级工程师,研究领域为结构仿真技术。
备注
提出了一种时域瞬态动力学仿真与频域功率谱密度分析结合的非线性模态仿真方法,仿真过程为:首先,应用周期图法与概率统计对随机试验条件进行时域拟合与验证,获取拟合时域条件并证明有效性; 然后,将其作为输入条件对阀门结构进行瞬态动力学仿真,对时域加速度结果曲线进行功率谱转换; 最后,由功率谱密度分析获得结构非线性模态频率。不同于传统线性特征值模态仿真原理,非线性模态仿真方法通过频域功率谱条件-时域拟合-时域仿真频域分析多个过程完成非线性模态分析,在时域仿真步骤中引入接触非线性影响。某电磁阀线圈螺纹松动模型采用保守边界所得线性模态仿真结果与试验偏差为8.96%,而进行摩擦因数标定后,考虑接触非线性影响的非线性模态频率仿真结果与试验偏为0.69%,优于线性仿真结果。
A nonlinear modal simulation method that combines time-domain transient dynamics simulation with frequency-domain power spectrum analysis was proposed.The simulation process is as follows: first, the periodogram method and probability statistics are used to simulate the random test conditions in the time domain.Combine and verify, obtain the fitting time domain conditions and prove the effectiveness, then use them as input conditions to conduct the transient dynamics simulation of the valve structure, perform the power spectrum conversion on the time domain acceleration result curve, and finally obtain the structural nonlinear modal frequency through the power spectrum analysis. Different from the traditional linear eigenvalue modal simulation principle, the nonlinear modal simulation method completes the nonlinear modal analysis through multiple processes of frequency domain power spectrum conditions-time domain fitting-time domain simulation-frequency domain analysis.The nonlinear effects of contact are introduced in the time domain simulation step.The thread loosening model ofa certain solenoid valve coiluses conservative boundaries for linear modal simulation, and the deviation between simulation results and experimental results is8.96.After the friction coefficient calibration, the nonlinear modal frequency simulation results and experimental deviation considering the nonlinear influence of contact are 0.69.The result is better than linear simulation results.