The Modeling And Analysis Of The Automotive Fuel Pump Flow-induced Noise

As the development of the computational fluid dynamics and the computer technology,using numerical simulation method to solve the flow noise of the blade machines becomes more convenient and faster.Automotive fuel pump,an important component of the fuel supply system,is also a major source of noise.However,there were relatively less studies on the noise of fuel pumps using numerical simulation tools.Therefore,in this article,the CFD method and aero-acoustics based on the FEM were used to do modeling and analysis on the flow-induced noise of the fuel pump.This dissertation aims to explore a precise numerical method to obtain the flow-induced noise of fuel pumps.The study on the influence of some important parameters on the noise was conducted.Firstly,a high-precision fluid hexahedral finite element mesh of the pump was established,of which the wall zone is densified and the wall y + value was close to 1.The SST turbulence model was selected for CFD calculations.Grid independent verification was made,indicating that the mesh size is small enough.In the same time,the calculation results agreed well with the experimental results.Simulation of transient flow conditions inside the pump was conducted.By the way the sound source data of wall dipole which is needed in the acoustic simulation was obtained.Analysis of the vortex,turbulence and pressure pulsations was made.Fuel tank pump system transfer path analysis was made and the main noise transfer mode was pointed out.Then the whole system was simplified based on the transfer path analysis.In consideration of the highest frequency,the finite element model of the fuel tank system was established,which include both acoustic and structural mesh.The type and location of the main sound source were analyzed,indicating that the flow channel wall dipole sound source was the main noise source caused by flow.The AML technology was used for acoustic-vibration coupling calculations.Pump noise test was conducted to verify the calculation results.The calculation sound pressure results agreed well with the experimental results in the high frequencies,especially in the blade passing frequency.The study on the influence of important parameters on flow-induced noise was conducted,indicating that the lower is the speed the higher is the blade passing frequency noise.The number of blades made the most influence on the amplitude of noise.,while The blade pitch angle and blade thickness made little influence on the blade passing frequency noise.The study on the influence of parameters on the performance of the pump was also conducted.It was found that mass flow rate,effective power and shaft power were respectively linear functions of speed.The higher is the speed the lower is the efficiency.All of the performance parameters of the pump were respectively monotonous functions of the structural parameters.