Development of the Electric Fuel System for the More Electric Engine

Abstract

This paper describes the experimental rig test result of the electric motor-driven fuel pump system for the MEE (More Electric Engine). The MEE is an aircraft engine system concept, which replaces conventional mechanical/hydraulic driven components with electric motor-driven components. Various MEE approaches have been studied since the early 2000s and one of its key concepts is an electric motor-driven fuel pump [1–4]. The authors commenced a feasibility study of the electric motor-driven gear pump system for what was assumed to be a small-sized turbofan engine. The concept study and system design were conducted, whereupon technical issues for the electric fuel pump system, which both supplies and meters fuel via the motor speed control, were clarified [5, 6]. Since one of the key issues is fuel-metering accuracy, the electric fuel system, including a flow feedback closed-loop control, was designed to ensure accurate fuel-flow metering for aircraft engine applications. To verify the rig system, an experimental model of the electric fuel pump system is assumed for a small-sized turbofan engine. The hardware of the motor-driven fuel pump and flow measurement mechanism, including an FPV (Fuel-Pressurizing Valve) and orifice, were designed, manufactured and fabricated and a differential pressure sensor for flow feedback was selected. Other equipment was also prepared, including a motor controller, power source and measurement devices, and the entire rig set-up was constructed. A bench test using the rig test set-up was conducted to verify the fuel-metering accuracy, response and system stability. Data, including the static performance and frequency response, were obtained for the electric motor, motor-driven fuel pump and entire fuel system respectively. The rig test results indicate the feasibility of the system, which will provide an accurate engine fuel flow (Wf) measurement and frequency response required for actual engine operation, via an electric motor speed control and fuel-flow feedback system, as proposed in the MEE electric fuel system.

Study of flow ripple characteristics in an innovative two-dimensional fuel piston pump

“…Due to advances in aero-engines and the prevalence of airborne multi-electrical power drives, there is an ever-increasing demand for fuel pumps with high efficiency and power density [1,2], as conventional gear pumps or axial piston pumps can hardly match the pace of progress in aero-engine technology. The efficiency of gear pumps decreases to unacceptable levels at high pressures and temperatures, which are routine operating conditions for modern advanced aeroengines [3].…”

Robust Control for Electric Fuel Pump with Variant Nonlinear Loads Based on a New Combined Sliding Mode Surface

“…temperature of fuel and power loss caused by wasting fan discharge air. Moreover, the fuel bypass is removed and AGB is simplified to enhance engine efficiency with improved SFC(Specific Fuel Consumption) [9]. Therefore, the electric fuel system will contribute to the reduction of engine power extraction to drive the fuel pump, leading to an improvement in engine efficiency.…”

“…After the application of EFP, the pump discharges exact fuel flow demanded by the FADEC, resulting in that a large part of performance of engine is depended on the property of intelligent controllers, which is crucial for aircraft safety. Besides, the FMU(Fuel Management Unit) [9] is eliminated in MEE, leading to the situation that the EFP itself will be used as a metering device, setting new request for controllers including accuracy,good dynamic performance, reliability and robustness.…”

Numerical and experimental investigations on flow regulation of fuel vapor core pump

“…3,4 At the same time, minimum weight and volume are almost overriding requirements for any fuel pumps employed on aeroengines. 5,6 A vapor core pump (VCP), developed from a centrifugal pump, is added an inlet throttling assembly to widely regulate the fuel flow instead of bypass throttling. Moreover, low power loss and temperature rise under small flow rate favor the adoption as afterburner pump.…”