Modal Analysis of the Aircraft Hydraulic-System Pipeline

Abstract

DOI: 10.2514/1.C031660 Inthispaperamodalanalysisofanaircrafthydraulic-pipelinevibrationiscarriedoutconsideringtheinfluenceof the fluid–structure interaction. Aircraft hydraulic pipes are always configured in curved rather than straight lines for the limited aircraft space. Therefore, the influence of curvature and friction of the pipeline should be accounted for in the vibration analysis. A mathematical model is developed to predict the vibration of the selected aircraft hydraulic-pipeline section. Vibration testing of the aircraft hydraulic pipeline is carried out, and comparison between the developed model and test is given, which illustrates that the developed model is correct. The research resultsalsoshowthatthemostimportantfactorfortheresonantfrequencyofthepipelinesectionisitslengthbetween the two supports, which can obviously increase the resonant frequency. The friction influence on the resonant frequency of the pipeline is less than the influence of the curvature. And the friction influence can reduce the stress response range, especially at the pressure peaks.