| Rotating machinery equipment as vibration source needs to predict the radiated noise and vibration status after it is installed in place before it is shipped or installed.At present,China basically adopts the post-evaluation method in this respect,the equipment will be tested after installation and commissioning.If the test results can not reach the expected technical specifications,it will bring great difficulties to the follow-up work.At the same time,the rotating mechanical equipment will adopt different mounting methods according to different demands in actual application,and it also needs to be connected with load when working,which will cause obvious changes in radiated noise and vibration state due to complex coupling effect.Therefore,it is necessary to know whether the mounting mode of base will affect the radiated noise of rotating machinery equipment.If the relationship between the mounting mode and the radiated noise of rotating machinery equipment can be established,it can be evaluated beforehand so as to forecast the radiated noise and vibration state of the base.It has very important engineering application value.This paper takes rotating machinery equipment as the research object,and the influence of changing the installation mode of the base on the vibration state and radiated noise of the rotating machinery equipment.The influence of changing the installation mode of the base,that is,changing the impedance condition of the base,the vibration state and mechanical impedance change of the base part under different base installation mode are studied from the simulation aspect.In the experimental aspect,the vertical three-phase asynchronous motor and horizontal one-way asynchronous motor are taken as the research objects,and the influence of changing the installation mode of the base on the base,the vibration state of the fuselage and the radiated sound power level is measured,the conclusions are as follows: 1.For rotating machinery,the mechanical impedance of the foundation is inversely proportional to the vibration response.When the mechanical impedance of the equipment increases,the speed decreases and the vibration decreases.2.Taking the free speed and foot admittance of rotating machinery as the source parameters,the corresponding vibration response can be converted by the impedance condition of the structure.The overall trend of the converted value is basically consistent with the measured value in the frequency band of 10hz-1khz.3.When the reverberation chamber method is used to measure the radiated sound power of sound source,if the sound energy is unevenly distributed in the reverberation chamber,the scanning method can be used to obtain more accurate measurement results.4.The vibration state of the installation foundation of rotating machinery will be greatly affected under different base installation methods.When fixed on the ground,the vibration below 1k Hz will be reduced.The rubber pad at the bottom is only different from the free installation state in the low frequency band.When the accuracy requirement is not high,it can be used as the free installation method of mechanical equipment.At the same time,different base installation methods are opposite The difference of sound power level is less than 1.5d B. |
PDF Full Text Request