The Research On Flow-induced Vibration Noise Of Roto-jet Pump

Today,with the rapid development of industry,the use of pumps is becoming more and more widespread.Inevitably,the requirements for all aspects of the pump also become strict,especially for noise.Noise is a kind of noise pollution in human living environment,which will seriously affect the quality of human life.The rotary jet pump is a small flow,high head of the very low specific speed pump,because its structure principle is similar to Pitot tube,also known as pitot pump.Because the design of the conventional centrifugal pump centrifugal supercharging principle and space technology in the stamping stagnation supercharging principle is composed of a simple structure,compact size,reliable seal,easy to operate,low maintenance cost,high pressure,the most stable operation of the single-stage high-pressure pump.It is suitable for petroleum,chemical industry,chemical fertilizer,metallurgy,mining,carbon black,papermaking and other industries.Of the jet grouting pump,this paper analyzes the internal flow field of jet pump,through the flow field of the sound source information,analyzes the jet grouting pump flow induced vibration noise of main noise source,through the study of the numerical simulation of the interior sound field,get inside the acoustic field characteristics,the analysis of the structural parameters of the change of the influence of flow field and acoustic field,for rotary spray pump noise optimization to provide certain reference.The main work of this paper is as follows:1.The research background of this subject is described,the working principle and structure characteristics of rotary jet pump are briefly introduced,the domestic and foreign research status of rotary jet pump and pump flow noise is summarized,and the CFX and virtual.lab acoustics software needed in this paper are introduced finally.2.The design theory and method of the long and short blade compound impeller and the collector pipe of the rotary jet pump are introduced.Based on the design method,the hydraulic design and three-dimensional modeling of the impeller and the collector pipe are carried out according to the design parameters.3.The flow control equation for numerical calculation of the flow field is briefly introduced,and the model is grid-divided and grid-independent tested by ICEM.CFX is used to simulate the internal flow field of the rotary jet pump.Taking the steady calculation result as the initial value,the pressure pulsation monitoring point is set in the special part of the rotary jet pump,the unsteady calculation is carried out on the rotary jet pump,the unsteady pressure and velocity distribution is analyzed,the pressure pulsation time domain diagram and frequency domain of each monitoring point are mainly analyzed,and the cause and location point of sound source are preliminarily obtained.4.The basic knowledge and basic parameters of acoustics are introduced,and the generation mechanism of flow induced vibration noise and the calculated flow field of sound field are analyzed.Based on the direct boundary element method,the internal radiated noise of the blade dipole sound source and the collector tube dipole sound source of the spinner pump was calculated by using the software of Virtual.lab acoustics.5.Key structural parameters were selected,and the flow field and sound field of the rotary jet pump were taken as the analysis target.By changing the structural parameters,the models with different structural parameters were obtained,and the flow field and sound field of each model were numerically simulated to obtain the corresponding flow field and sound field characteristics,and the flow field and sound field rules were compared.Finally,the influence of each structure parameter on the flow field and sound field was obtained.