Modal Analysis Of The TA-80 Reciprocating Compressor

Compressor is used to increase the gas pressure and transport gas, which is widely used in chemistry, petroleum, mine, metallurgy, mechanism, refrigeration and national defense industry. It is one of the indispensable key equipments. The vibration is a main reason to make compressor failure. It is very important to study theoretically and practically the dynamic characteristics of a compressor. Based on the finite element simulation and modal test, the dynamic characteristics of the TA-80 reciprocating compressor are discussed in this thesis. The main contributions of this thesis are summarized as follows:(1) By use of both software SolidWorks and ANSYS, the three-dimension solid model and finite element model of this compressor are established respectively. The bolting assembly relationship between the gas container and crankcase or electric machine is handled by using the MPC algorithm, and the contact boundary condition between the compressor and rigid plane is brought into simulating the single restraint between the compressor and the ground. The numerical result for modal analysis of the compressor is obtained.(2) A simple test method is developed to measure the modal of the compressor. By establishing modal test system, the test result for modal analysis of the compressor is given.(3) The comparison between the numerical result and modal test result shows that the former could provide good prediction for the dynamic characteristic of the TA-80 reciprocating compressor, so that the finite element model is valid and could be adopted in the failure diagnosis of the compressor.(4) To make use of the change of natural frequency to discern the failure in the crankshaft, some finite element models are proposed to study the modals of the crankshaft with and without transverse crack. It made a foundation for the development of the diagnosis and forecast technology of crankshaft.This thesis could provide an important reference for the dynamic characteristic analysis of the whole compressor. And the research for the influence of transverse crack on modal of the crankshaft makes a foundation for the building of a table of compressor failure signal.