Frequency Response Analysis of Fluid-Structure Interaction Vibration in Aircraft Bending Hydraulic Pipe

航空弯曲液压管路流固耦合振动频响分析

¹ Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control, Yanshan University, Qinhuangdao 066004, China
² Nanjing Engineering Institute of Aircraft System Jincheng AVIC, Nanjing 210000, China
³ Key Laboratory of Advanced Forging & Stamping Technology and Science, Ministry of Education of China(Yanshan University), Qinhuangdao 066004, China

Received: 8 April 2017

Abstract

For the aviation bending pipe, the fluid-structure interaction 14-equation model is established, and the Laplace transform is used to solve the problem in the frequency domain. For the pipeline with a single elbow, the influence of bending parameters on the frequency response of the pipeline in the frequency domain is analyzed by using the 14-equation. At the same time, for pipelines containing two elbows, we analyze the influence of bending parameters on the natural frequency of the pipeline in different spans. In the end, the accuracy of the simulation is verified by the modal knocking test. Through the above analysis, we reach the following conclusion:the bending angle of the pipeline is greatly influenced by inherent characteristics, the smaller the bending angle, the higher the pipeline’s inherent frequency domain. However, the effect of bending radius will cause the change in length. Usually, the increase of bending radius leads to pipe length increasing, resulting in its inherent frequency decreasing.

摘要

针对航空弯曲管路，建立其流固耦合14-方程模型，并利用拉氏变换将其变换至频域进行求解；对含单个弯管的管路，利用14-方程分析在管路长度变化及不变化时，弯曲参数对管路频域响应的影响规律；同时，对含2个弯管的管路，分析不同跨度时，弯曲参数对管路固有频率的影响；最终，通过模态敲击实验，验证仿真的准确性。经过上述分析，得到以下结论：弯曲角度对管路固有特性影响较大，弯曲角度越小，管路固有频域越高，然而，弯曲半径的影响在于是否会造成管长变化，通常情况下，弯曲半径的增加会导致管路长度增加，从而导致其固有频率降低。