| Compressor is a kind of general machinery,which can produce high pressure air and large vibration and noise.The compressor frame as loading parts directly connect with the vibration source and has a great impact on the vibration of compressor.Drastic vibration of the frame not only reduces its reliability,but also damages the frame,so it is necessary to study the vibration characteristics of the frame.Through consulting a large number of data,it is found that most of the researchers often analyze the vibration of a single component but the vibration of the parts system is very rare.Therefore,the vibration characteristics of the compressor frame under the assembly condition are analyzed and studied in this paper.Firstly,the geometry model of the compressor frame is established by using the three-dimensional modeling software Solidworks,and the frame is equipped with diesel engine,main pump,fuel tank and other components.The fuel tank is made of sheet metal,and the rigidity is small,so the geometric model of the tank is connected with the frame as a whole.Other components can be used as a centralized quality due to their big rigidity.Then,the geometric model is simplified reasonably,and the boundary conditions of the model and the element type are determined.Finally,the finite element model of the compressor frame is set up by using Hypermesh software.Secondly,the modal analysis is carried out under the condition of assembly,and modal parameters are obtained.The modal frequencies of the frame are compared with the free modal frequencies and the test modal frequencies,The results show that the modal parameters of the frame under the condition of assembly more in line with the actual situation,and the vibration characteristics are preliminarily understood.The frequency response of the frame system is analyzed on the basis of modal analysis.The excitation of the engine is analyzed and calculated,and the input excitation of the frequency response analysis is obtained,and the response of the frame under harmonic excitation is analyzed by using the Radioss solver.At the same time,the frame is tested by LMS vibration testing equipment to verify the accuracy of the simulation results,the results show that the frame under the condition of assembly will resonate when full loading.Finally,based on the modal analysis and frequency response analysis of the compressor frame under the assembly conditions,the improvement of the frame is presented.The vibration test and noise test of the compressor before and after improvement are carried out,and the results of vibration test and noise test are compared and analyzed.The results show that the average value of vibration speed is reduced by 1.5mm/s,and the average noise value is reduced by about 7 d B.In this paper,the vibration characteristics of the compressor frame under assembly condition is analyzed,the simulation and test results show that the vibration characteristics of the frame under the assembly condition are more realistic,it provides the basis for the improvement and subsequent design of compression frame and other machine frame. |
