| Squeeze film damper(SFD)technology is most widely used in the aero-engine for reducing vibration at present.SFD has high reliability simple structure.Meanwhile,the vibration reduction effect of SFD is remarkable.In this paper,the dynamic characteristics of the squeeze film damper are obtained through theoretical calculation and experimental study for the SFD structure of the actual compressor rotor.The research results have important practical application value in engineering for the development of a certain type of engine and ensuring the safe operation of the engine rotor.The main results are obtained as follows:(1)The dynamic calculation and analysis model of squeeze film damper without supply groove configuration is established based on hydrodynamics,Reynolds equation Analytical method based on Short Bearing Hypothesis,finite differential method and Fluent simulation method are used to get the film pressure distribution of the SFD model.The film pressure distribution and characteristics of the model are studied and compared.The results of the three methods are consistent for the model without supply groove and show that the calculation methods and results of the analysis model are effective.(2)The calculation and analysis model of SFD with supply groove configuration is established based on the actual structure of squeeze film damper for a Compressor Rotor.The results show that only the finite differential method and the Fluent simulation method are applicable when considering the configuration of the supply groove.For the compressor rotor SFD structure,the influence of the supply groove on the film characteristics is huge.The position of the supply groove has a great influence on the film characteristics.Based on the analysis results of this paper,side grooving is recommended in the engineering in the three grooving positions;central grooving,1/4 position grooving.and side grooving;(3)The effects of dynamic eccentricity,film clearance,supply temperature and pressure,static eccentricity and end seal configuration on the dynamic characteristics of the actual compressor rotor SFD structure were studied by finite differential method and Fluent simulation.The results show that when the dynamic eccentricity and static eccentricity are large,the film characteristics will show strong nonlinearity;film stiffness value is too large when film clearance value is small;Fluent simulation analysis shows that the supply pressure only affects the local pressure of the film,while the experimental study shows that it will increase the global film pressure value.Therefore,the influence of supply pressure on the characteristics of SFD needs to be studied deeply in combination with experiments in order to meet the requirements of engineering applications;the influence of end seal configuration was preliminarily explored.The results show that the end seal is beneficial to enhance the pressure distribution of SFD and the future research directions were proposed.(4)A bi-directional excitation tester was designed to study the film pressure variation for SFD with and without end seal under different excitation frequencies,different dynamic eccentricity,different supply temperatures and pressures.The comparison of the two methods proves the effectiveness of the end seal.The rationality of the theoretical model is verified by comparing the experimental results with the theoretical results.The study results of the paper have strong theoretical guidance and practical application of engineering for the he actual compressor rotor SFD structure. |
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