Characteristic Analysis And Test Of Pressure Pulsation Of Centrifugal Pump

The centrifugal pump produces both static and dynamic pressure components at the same time,the dynamic pressure component is pressure pulsation,and the pressure pulsation is superimposed on the static pressure component like the AC signal.The pressure pulsation will stimulate the mechanical vibration of the pump body and pipeline,affect the normal operation of the pump and reduce the service life of the pump.It is of practical significance to study the pressure pulsation in centrifugal pumps.In this paper,the CFD(Computational Fluid Dynamics)technology Fluent software is used to monitor the pressure fluctuation in the impeller and the volute,so as to reveal the relationship between the pressure pulsation and the performance of the centrifugal pump,so as to provide the basis for further prediction of the pressure pulsation induced by the unsteady flow of the centrifugal pump.Based on the standard k-? turbulence model,Fluent software is applied to the steady and unsteady three-dimensional simulation of the flow field in the centrifugal pump,and the accurate internal flow field characteristics and the pressure fluctuation of the monitoring point are obtained.The scheme of the measurement system is designed.First,the parameters,functions and principles of the pressure transmitter and data acquisition module are fully grasps to complete the selection of the hardware and the drawing of the circuit wiring diagram.The upper computer is written by Labview software,and the data of the 8 channels are collected continuously through the system settings,sampling and display and so on.The display of the waveform curve.The results show that under the condition of small flow,the pressure fluctuation level of each monitoring point is higher because of the unsteady flow of the flow field in the centrifugal pump,and the vortex and reflux at the tongue and outlet of the volute cause the pressure fluctuation obviously.It can be seen that the pressure pulsation is caused by the non design conditions,so the inlet speed and flow rate of the fluid must be strictly controlled in the centrifugal pump operation,so that the centrifugal pump can work steadily under the standard flow condition.Because of the dynamic and static interference between the impeller and the volute and the function of the complex basin,the tongue of the volute can cause a strong pressure pulsation even under the design condition.For the effective reduction of the pressurefluctuation,the center of gravity can be placed on the asymmetrical structure of the tongue separates because of the uncontrollability of the dynamic and static interference.The pressure pulsation should be prevented and controlled when the parameters of the body model are needed.The pressure fluctuation in the diffuser of the volute is very gentle,which is mainly due to the buffering and steady flow of the diffusion section.