The Analysis And Design Of The Vibration Monitoring System Of The Impeller

Centrifugal compressors are widely used in many fields of industrial production and they depend on the pressure of the impeller and the expansion of the diffuser to raise the gas pressure.The centrifugal impeller is the core component of the centrifugal compressor which forced by the air compressor alternating load and high-speed operation while working.It can lead to crack initiation and expansion in the impeller blade root after a certain period of time.Tiny cracks expand gradually with the increasing alternating load cycles.Even more serious,the blade fatigue fracture can lead to production accidents.Failure of the impeller directly affect safety and stable operation of the compressor,so carrying out the analysis and design of the vibration monitoring system of the impeller to ensure the safe running of the equipment and saving the cost in order to improve economic efficiency is of big significance.The main research work of this paper is as follows:First,this paper will establishe the dynamic model of centrifugal impeller with lumped mass model.We will obtained the variation law of the stiffness of the blade corresponding to different cracks according to the equation deduced by mechanical formula.We will apply the Ansys Bladegen modeling module and the Pro/E software to build the impeller model,and then we will conduct the blade stiffness parameter by static analysis of blade in Workbench.Secondly,the AMESim model will be built according to the lumped mass model.We will simulate the effects of different crack depths and different crack distribution and summarized the influence law according to finite element analysis and calculation before which provide the theoretical basis for the design of the vibration monitoring system of the impeller.Finally,we will use tip –timing measuring method of non contact measurement for data acquisition.After data processing we will set alarm device to conduct the design of online monitoring system for the running state of the impeller by analysis the requirements of this software based on LabVIEW.The fast modeling method of impeller will be used in this paper.Impeller vibration response model will be established to analyzed the effect of cracks on the blade to vibration response.Impeller vibration detection software will be developed which provides technical support and monitoring measures for impeller fault detection and avoiding the occurrence of major accidents.