Noise Characteristics Analysis And Application Of Centrifugal Pump

The centrifugal pump will produce noise whether it is in a normal working state or a faulty state.While these noise signals bring noise pollution,they also contain a wealth of information about the operation of the centrifugal pump.In the past,the analysis and application of noise signals of centrifugal pumps mainly focused on noise reduction reconstruction and fault diagnosis based on sound pressure value.However,noise reduction transformation based on sound pressure value often cannot effectively solve the problem of noise pollution,and the rich equipment operation information contained in the noise signal can also be used to monitor the operating status of centrifugal pumps,in order to solve the traditional status The problem of insufficient monitoring accuracy of monitoring equipment provides new ideas.Therefore,based on the in-depth analysis of the noise characteristics of the centrifugal pump,this article directly reflects the efficiency change of the centrifugal pump based on the noise signal of the centrifugal pump,and proposes a simple and effective theoretical calculation method for guiding the noise reduction transformation of the centrifugal pump.This paper analyzes the noise of the two centrifugal pumps actually put into use and the centrifugal pumps under different operating conditions in the laboratory.Through the analysis of the noise characteristics of the centrifugal pumps actually put into use,it is pointed out that when the noise reduction transformation of the centrifugal pump is carried out,the targeted transformation scheme based on the analysis of the noise characteristics of the centrifugal pump can be the most effective solution to the noise problem.When the proportion of high-frequency noise is higher,a noise reduction plan based on sound absorption and noise reduction is required.When low-frequency noise is the main noise source,a noise reduction plan based on vibration reduction should be adopted.For the selection of vibration damping equipment,this article gives a calculation method for calculating the noise energy required by noise reduction equipment based on vibration acceleration and building parameters,which is used to guide the selection of vibration damping equipment.In the laboratory,the rotation speed of the centrifugal pump is changed through the frequency converter,so that the centrifugal pump is operated under the small flow condition,the rated flow condition and the large flow condition respectively,and the noise characteristics of the centrifugal pump under different operating conditions are analyzed.Combining the methods of EMD and spectrum analysis,the complex noise of the centrifugal pump is decoupled into a noise component with a single characteristic.Through the analysis of the characteristic change trend,it shows that there are characteristic components in the noise signal that can reflect the change of the efficiency of the centrifugal pump with the flow rate.The change of this characteristic component is mainly reflected in the change of the frequency characteristic.With the change of the flow rate of the centrifugal pump,the noise frequency appears to be consistent with the change of the efficiency of the centrifugal pump.The frequency of this noise component is the highest when operating under rated conditions,and when it deviates from the rated conditions,the frequency of this noise component decreases.Based on theoretical calculations and analysis of the internal flow field of the centrifugal pump,the validity of this conclusion is proved,which shows that the efficiency monitoring of the centrifugal pump based on the analysis of noise signal characteristics is feasible.