基于瑞利-里兹法的低翅片管固有频率数值解

针对低翅片管几何形状复杂,质量和刚度分布不均匀,振动特征值不能有封闭解的问题,采用瑞利-里兹法对低翅片管的固有频率进行了数值研究,获得了低翅片管弯曲振动固有频率的数值计算模型。对于一定规格的低翅片管,应用该数值计算模型可求得其各阶固有频率的数值解。采用共振法测试了低翅片管的固有频率,前三阶固有频率的数值解与实测值相比,误差范围为-3.28%--3.51%。该数值计算模型可用于低翅片管固有频率的求解。

Numerical Solution of Natural Frequencies of Low-finned Tubes Based on Rayleigh-ritz Method

Due to the complication of the geometric shape and the non- uniform distribution of the mass and stiffness, it is impossible to obtain the exact solution of natural frequencies of low - firmed tubes. The numerical study of natural frequencies of low- firmed tubes was done by means of Rayleigh - Ritz Method, and the numerical calculation model was obtained. The numerical solutions of natural frequencies can be calculated by using this numerical calculation model for the low- firmed tube with specified size. The natural frequencies of low - firmed tube were tested by use of the resonance method. It is found that the numerical solutions are close to the measured values and the deviations between calculated and measured values for the first three natural frequencies are in range of - 3.28 % - - 3.51%. This model can be used to calculate the value of natural frequencies of low- firmed tubes.