Research On Dynamic & Static Characteristics Of A Comprehensive Test Bench For Hydraulic Dampers

Hydraulic dampers have been widely used in both military and civilian projects. In order to test the performance characteristics and quality of a hydraulic damper, it is necessary to construct a test system for hydraulic dampers. The comprehensive performance test bench for hydraulic dampers, which should possess reliable features such as high precision, large load exertion capability and wide responding frequency band, is indispensable in order to test the comprehensive performance of hydraulic dampers. Therefore, both the dynamic and static characteristics of the test bench must satisfy high requirements.Using the software ANSYS, this thesis analyzed the dynamic and static characteristics of the test bench and obtained many fundamental parameters such as the clamping force generated, the inherent frequency, et al. Moreover, it is testified that the static analysis model of the test bench is correct by means of experiments.Firstly, the structure and operation principle of the test bench for hydraulic dampers were analyzed. As a result, several forms of the structure failure of the test bench when it is in operation were put forward.Secondly, the clamp framework's 3-D model was built using Ansys Parameter Design Language(APDL), and then the model was meshed. By simulating the real conditions, external pressure and DOF restrictions were applied. Therefore, the finite element model was built. By means of static contact analysis, the clamping force and the maximal stress were calculated, and the relationship between the clamping force and the outside pressure was further illustrated. The results indicate that the clamping force produced by the test bench can ensure that the test bench can be dependably clasped, which provides the computational reference to the structure design of the test bench. The result of experiments and calculation fit quite well.Thirdly, the boundary conditions of the test bench were applied on the test bench with no load, as a result, the finite element model of the test bench was built. By means of modal analysis and harmonic analysis, it is concluded that the inherent frequency is much higher than the working frequency, which proves that the resonance of the system will not occur.Finally, the vacuum generating and oil injecting system is a part of the comprehensive performance test system for hydraulic dampers, whose function is to generate a vacuum inside the hydraulic dampers and inject oil into them. After the design requirements for the system and the structure of the hydraulic dampers were analyzed, the operation principle of the system was brought forward, and the system has been actually manufactured.