Analysis Of Characteristics Of Aero-engine Fuel Pump Regulator

The fuel pump regulator can adjust the amount of fuel supplied to the combustion chamber according to different working conditions.Its performance determines the reliability of the aviation engine fuel control system.Research on the fuel pump regulator’s operating characteristics is of great significance for the control and optimization of aircraft engines.However,there are problems such as the uncertainty of the pressure and flow of each node position under different working conditions and the fatigue fracture under vibration.Therefore,the paper focuses on the working characteristics of the fuel pump regulator,and carries out the hydraulic performance analysis of the system and the fatigue characteristics analysis of the key component protection cover,which can provide theoretical basis and data support for the performance prediction,parameter optimization and system upgrade of the fuel pump regulator.These studies have important practical value and application significance.The main work of this paper is as follows:Firstly,a fuel pump hydraulic system simulation model including metering valve,differential pressure valve,parking valve,fuel combination pump,etc.was built to study the system outlet flow and metering valve front and back pressure changes with valve opening,pump speed and load pressure.The steady-state and dynamic characteristics of the fuel pump regulator under typical working conditions were analyzed,and the accuracy of the simulation model was compared through the hydraulic performance test.The error of the two is controlled within 5%under steadystate conditions,and within 10%under dynamic conditions.Secondly,the finite element model of the differential pressure valve was constructed,and the CFD flow model under the relevant design parameters was obtained to capture the flow field characteristic distribution law inside the valve.Then,the influence of design parameters such as the overflow hole type of the valve,the oil pressure acting area of the control chamber and the spring structure on the device characteristics was analyzed.Through analysis,it is found that the increase of the number of overflow holes will lead to the increase of oil return,and reduce the outlet flow of the system.The increase of the pressure differential valve spring stiffness will lead to the increase of the outlet flow of the system.The increase of the oil pressure area of the differential pressure valve will improve the steady-state error of the system,but also lead to the increase of the volume and weight of the device.Thirdly,the finite element model of the protective cover belt test tooling was built,and the frequency response of the structure was calculated,and the transfer function of the structure was obtained.Then,the S-N curve of 3D-printed aluminum alloy material was obtained through experiments.Finally,using the finite element fatigue analysis software and the given power spectral density(PSD)test load,the vibration fatigue condition of the fuel pump regulator protective cover device was analyzed from the frequency domain,the stress characteristic curve of the protective cover was obtained,the fatigue life curve under the given load was obtained,and a fatigue characteristic simulation analysis method was formed.