轴力对梁结构耦合损耗因子的影响研究

Effects of axial force on coupling loss factor of beam structures

以飞行器中经常使用的耦合梁结构为研究对象,使用点阻抗法分析受到轴力作用耦合梁结构的高频振动传递特性。在考虑梁耦合角度和激励频率变化的情况下,分析轴力对结构振动方程的影响,计算了耦合边界处的耦合损耗因子;选用‘一字梁’模型计算了温度变化对梁结构间传递特性的影响,并通过与有限元结果的对比验证了点阻抗法计算的正确性。结果表明:当面外弯曲波入射时,轴力对梁结构间的传递特性有明显的影响,但随着频率的增加逐渐减小;同时,温度对结构间的耦合损耗因子有明显影响,随着温度的升高,结构间的功率传递减弱。

Here,the point impedance method was used to analyze high frequency vibration transfer characteristics of coupled beam structures subjected to axial force.Considering beam structure coupling and excitation frequency varying,effects of axial force on beam structure vibration equation was analyzed,and the coupling loss factor at the coupled boundary was calculated.The"line-beam"model was used to calculate effects of temperature variation on transfer characteristics between beams.The correctness of the point impedance method was verified by comparing its calculation results with those of the finite element method.Results showed that when the out-of-plane bending wave is incident,axial force has an obvious effect on transfer characteristics between beam structures,but this effect decreases gradually with increase in excitation frequency;temperature obviously affects the coupling loss factor between beams,with increase in temperature,power transfer between beam structures weakens.