充液管路固有频率试验与计算分析

Experiment and Numerical Analysis of Natural Frequency for Liquid-Filled Pipe

为验证用有限元法计算充液管路固有频率特性的有效性,实现充液管路振动特性仿真,分别采用有限元分析和试验测试手段,对充液管路固有频率进行了试验和计算分析。对自由状态的空管、填充滑油和填充燃油三种状况的管路应用锤击法进行了振动测量,同时用ANSYS有限元分析系统对这三种状况管路固有频率进行了计算。通过计算与试验,分析了不同管径、不同管材、流体压力和流速、温度等因素对固有频率的影响,特别是得到了充液管路对比空管的固有频率下降规律,构建了考虑充液等因素的航空发动机管路固有频率计算模型。

In order to confirm the validity of calculating natural frequencies for filling liquid pipe by the FEA,natural frequencies were measured and calculated for aero-engine pipes with liquid by the FEA and experiment. Using the hammering method vibration feature was obtained experimentally for pipes which are either empty, or filling with lubrication oil or filling with fuel, and the natural frequencies were calculated by the FEA with ANSYS software. The affecting factors were analyzed on natural frequencies for pipe diameter, pipe material, liquid pressure, liquid velocity and temperature. Especially, the numerical value of frequen- cy decreasing trend was obtained with filling liquid pipe. The calculation model of natural frequencies was built up including several factors such as filling liquid. The technology foundation is established for analy- zing pipe vibration features.