Noise Prediction And Determination Of Casing Thickness For Large Scale Centrifugal Compressor Structure

With the continuous development of modern industry,the demand for large-scale centrifugal compressor units in various petrochemical plants is increasing,and the increasing power of centrifugal compressor units leads to the increasing noise emission of units.Noise has a serious impact on people’s physiology and psychology.At the same time,in the relevant international and domestic standards on noise,there are strict requirements for the noise indicators of machinery and equipment.Noise prediction and noise control of large centrifugal compressors have become urgent.Based on the fact that the noise of DMCL1104+2MCL1105+MCL806 cracked gas centrifugal compressor unit produced by SBW in Maoming Branch of Sinopec is high(the measured noise value is 104dB),the noise prediction of low pressure cylinder DMCL1104 in centrifugal compressor is carried out by numerical calculation and analysis,and the effect of the wall thickness of centrifugal compressor on the structural noise is studied.The influence of radiation can optimize the design of centrifugal compressor unit and reduce the noise radiated by centrifugal compressor unit.The 3D model of DMCL1104 centrifugal compressor shell is established by SolidWorks software;the finite element model of the shell is established by ANSYS software,and the modal analysis and harmonic response dynamic analysis of the shell are carried out to study the vibration characteristics of the shell and obtain the vibration speed and displacement of each node on the shell surface;the boundary element model of the shell surface is established by ANSYS software,and the LMS is adopted.Virtual.Lab Acoustics simulation software carries out acoustic calculation of the model and studies the acoustic radiation characteristics of the shell;compares the calculated results with the measured results to verify the reliability of the calculation;optimizes the shell of the centrifugal compressor according to the vibration and acoustic radiation characteristics of the shell,and simulates the optimized model to verify the vibration and noise of the optimized shell.Through the noise simulation calculation of five different improvement schemes,the best centrifugal compressor block model can be obtained by comparing the total sound power level and the noise results of each field point in the surrounding sound field.This model has the smallest noise radiation in all models,and can reduce the vibration radiation noise of centrifugal compressor body well.By comparing the measured data with the theoretical analysis data on the centrifugal compressor test workshop of SBW,the measured results are basically consistent with the theoretical analysis and prediction results,and the noise value of the unit running in the user site also meets the requirements of relevant technical standards.