Micro Fuel Pump Technology Benefits Small, Heavy-Fuel Engines

  • Published
  • By Tom Brown
  • Aerospace Systems
WRIGHT-PATTERSON AIR FORCE BASE, Ohio --  The rapid growth of Unmanned Aircraft Systems (UAS) used across the Department of Defense (DoD) has introduced propulsion system logistics support and operational power issues. One primary issue is the multitude of propulsion systems designed to use a variety of sometimes difficult to obtain fuels instead of commonly available JP-8. Additionally, the small engines typically used do not characteristically have adequate power, durability and reliability needed for many DoD mission scenarios.

In response to these challenges, the Air Force Research Laboratory (AFRL) Propulsion Directorate's Efficient Small Scale Propulsion (ESSP) program focused on UAS engine component enhancement initiatives, including fuel pump capabilities. The ESSP office teamed with Turnkey Design Services, LLC, of Blue Island, Illinois, to develop a "smart" micro fuel metering pump to address the limitations of conventional UAS fuel system pump durability, reliability and compatibility for operation on JP-8 fuel.

The Turnkey Design Systems' miniature, lightweight fixed displacement pump developed for UAS applications is driven by a highly reliable permanent magnet, brushless motor that is controlled by "smart" electronics. The integration of smart electronics:

· Incorporates the capability of setting the required minimum and maximum flow
· Prevents pump or system damage by limiting current draw
· Maintains constant pump flow over the entire operating temperature range
· Enables high flow accuracy and transient response
· Provides health monitoring and predicts remaining pump life

The MFP30-1 can be programmed to power engines between 7-60 shaft horsepower (SHP) and can provide flows up to 11 gallons per hour and pressures up to 100 PSID. A pump to power 200-300 SHP engines has also been developed. Over 300 hours of endurance testing has been completed and the pump technology has been matured to Technology Readiness Level 6.

The MFP30-1 technology can be utilized in numerous applications. Designed as flow metering device for gas turbine engines, it can also be used in a common rail fuel injection system. Because of its pressure regulating accuracy and transient response capability, a fuel injector pressure regulating valve is not needed. This technology was developed for unmanned aerial vehicles but other markets have evolved, including lightweight portable power generation systems, turbocharger oil scavenge pumps, medical infusion therapy applications and supplying water and methanol to fuel cells.