Fuel System Design for the More Electric Engine

2012 ◽  
Author(s):  
Noriko Morioka ◽  
Hitoshi Oyori
Keyword(s):  
System Design ◽  
Feedback System ◽  
Gear Pump ◽  
Fuel System ◽  
Pump System ◽  
Fuel Pump ◽  
Technical Challenge ◽  
Speed Range ◽  
Technical Challenges ◽  
Electric Engine

This paper describes the system design of an electric motor-driven fuel pump system for the MEE (More Electric Engine). The MEE is a new aircraft engine system concept which will reduce fuel burn and CO2 emissions, and improve engine safety, reliability and maintainability. At the initial concept design stage of the MEE, a feasibility study indicated that the electric fuel pump system helped improve engine efficiency. The selected fuel pump system configuration for the MEE was a fixed displacement gear pump system, the speed of which is controlled by an electric motor. Simplification of the fuel system will be expected because the electric gear pump itself is used as a metering device, but there are several technical challenges which should be overcome to realize the system. One of the technical challenges involves ensuring fuel metering accuracy via motor speed control. To address the issue, studies of the fuel flow rate feedback system were performed. A novel flow feedback system was investigated and the potential to ensure metering accuracy was confirmed. The other technical challenge is the wide speed range operation of the gear pump system. If only a single electric gear pump is used in the MEE system, the pump should accommodate a speed range of 5 to 100% because the ground starting flow rate is about 5% of the maximum flow. Operation at such low speeds is significantly harsh for the LP pump pressurizing capability and bearing film lubrication. However, optimized pump performance and operational condition were established, and it is expected that a single pump system, in which both LP and HP pumps are directly motor-driven via a single shaft, can be constructed. In addition, there is a technical challenge involved in supplying electrical power to the pump motor during the windmill engine start-up. The system design focused on the above technical challenges, and the consequent feasibility of the simplified MEE fuel pump system construction was confirmed.

Development of the Electric Fuel System for the More Electric Engine

2014 ◽  
Author(s):  
Noriko Morioka ◽  
Hitoshi Oyori ◽  
Yukinori Gonda ◽  
Kenji Takamiya ◽  
Yasuhiko Yamamoto
Keyword(s):  
Electric Motor ◽  
Aircraft Engine ◽  
Fuel System ◽  
Motor Speed ◽  
Pump System ◽  
Fuel Pump ◽  
Fuel Flow ◽  
Set Up ◽  
Electric Fuel Pump ◽  
Electric Engine

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.

Development of Double Gear Fuel Pump for Heat Management Improvement

2010 ◽  
Vol 132 (8) ◽  
Author(s):  
Yasushi Matsunaga ◽  
Noriko Morioka ◽  
Seiei Masuda ◽  
Masahiro Kurosaki
Keyword(s):  
Fuel Consumption ◽  
High Efficiency ◽  
Mode Switching ◽  
Gear Pump ◽  
Management Problem ◽  
Fuel Temperature ◽  
Heat Management ◽  
Pump System ◽  
Fuel Pump ◽  
Pump Speed

A unique double gear fuel pump system with operation mode switching capability for aircraft engines was developed to solve the heat management problem of current high efficiency turbofan engines and improve specific fuel consumption (SFC). Mode switching from parallel operations to series operations was found to reduce the discharge flow and pump work to nearly half. This resulted in the reduction of the rise in fuel temperature due to the fuel recirculation at the high altitude low Mach number flight condition. Air cooled oil cooler (ACOC) is usually required for sufficient oil cooling at descent or approach flight conditions. Since fuel consumption at those conditions is not very high, most of the gear pump discharge fuel flow proportional to the engine speed is returned to the fuel pump inlet resulting in significant heating. The ACOC that provides additional cooling capability degrades SFC due not only to the increased weight but also to the wasted fan discharge air. By reducing fuel temperature rise at the pump at those flight conditions, the necessity of ACOC may be eliminated. Further, it is shown that a reduction by half of the double gear pump weight can be achieved by increasing pump speed twice without incurring a durability penalty. Extensive tests showed sufficient steady state pump performance, switching characteristics, and durability.

Development of Fuel Control System for More Electric Engine

2015 ◽  
Author(s):  
Naoki Seki ◽  
Noriko Morioka ◽  
Hitoshi Oyori ◽  
Yasuhiko Yamamoto
Keyword(s):  
Control Method ◽  
Pressure Oscillation ◽  
System Stability ◽  
Gear Pump ◽  
Engine Fuel ◽  
Fuel System ◽  
Loop Control ◽  
Fuel Flow ◽  
Electric Engine ◽  
Experimental Rig

This paper describes the experimental rig test result and an investigation into issues of system stability and pressure oscillation transmission in the MEE (More Electric Engine) fuel system. This system employs an electric motor-driven pump and directly meters the fuel flow based on the motor rotating speed. The MEE is a system architecture concept for the aircraft turbine engine that reduces fuel consumption and environmental load while improving safety, reliability and maintainability. The improvements were demonstrated by conducting a feasibility study of MEE system for small sized turbofan engine [5, 6]. The authors also conducted an experimental rig test showing capabilities in terms of fuel-metering range, accuracy and response [7]. The capability of the feedback loop control under the engine start condition was shown by the result, but meanwhile, pressure oscillation under the higher fuel flow condition was also observed. The authors repeated the rig test to investigate its root cause. This paper describes the study, which investigates the characteristics of the MEE fuel system and seeks stable control methods under conditions of higher pressure fluctuation, higher instrumentation noise or applying worn gear pump. The paper also describes the study of the pressure oscillation transmission from pump to engine combustor, which may damage the engine combustor and structures. As a result of these studies, a novel control method for the MEE fuel system is proposed, with improved oscillation stability.

Development of Double Gear Fuel Pump for Heat Managment Improvement

2006 ◽  
Author(s):  
Yasushi Matsunaga ◽  
Noriko Morioka ◽  
Seiei Masuda ◽  
Masahiro Kurosaki
Keyword(s):  
Fuel Consumption ◽  
High Efficiency ◽  
Operation Mode ◽  
Mode Switching ◽  
Gear Pump ◽  
Management Problem ◽  
Fuel Temperature ◽  
Pump System ◽  
Fuel Pump ◽  
Pump Speed

A unique double gear fuel pump system with operation mode switching capability for aircraft engines was developed to solve the heat management problem of current high efficiency turbofan engines and improve Specific Fuel Consumption (SFC). Mode switching from parallel operations to series operations was found to reduce the discharge flow and pump work to nearly half. This resulted in the reduction of the rise in fuel temperature due to the fuel re-circulation at the high altitude low Mach number flight condition. Air Cooled Oil Cooler (ACOC) is usually required for sufficient oil cooling at decent or approach flight conditions. Since fuel consumption at those conditions is not very high, most of the gear pump discharge fuel flow proportional to the engine speed is returned to the fuel pump inlet resulting in significant heating. The ACOC that provides additional cooling capability degrades SFC due to not only increased weight but also wasted fan discharge air. By reducing fuel temperature rise at the pump at those flight conditions, the necessity of ACOC may be eliminated. Further, it is shown that a reduction by half of the double gear pump weight can be achieved by increasing pump speed twice (2x) without incurring a durability penalty. Extensive tests showed sufficient steady state pump performance, switching characteristics, and durability.

Fuel system design of the smart UAV considering operational reliability

2006 ◽  
Vol 78 (3) ◽  
pp. 204-210
Author(s):  
Changduk Kong ◽  
Myoung‐cheol Kang ◽  
Chang‐ho Lee ◽  
Dong‐ju Han
Keyword(s):  
System Design ◽  
Operational Reliability ◽  
Fuel System
Sign in / Sign up

Export Citation Format

Share Document