Advanced High-Speed Fuel Pumps for Small Gas-Turbine Engines

摘要

The object of the program was to develop the technology necessary for vane-pump operation at turbine rotational speeds. Major hardware emphasis was devoted to the evaluation of a high-speed fuel pump based upon this technology. A single-lobe vane pump with a centrifugal charging stage was designed and successfully operated at 40,000 rpm pumping JP-4 turbine fuel. The vane pump relies upon the use of a hydrodynamically lubricated pivoting vane tip to support vane assembly radial loading. The hydrodynamic film allows a significant increase in tip surface speed without sacrificing the required endurance life. A 200-hour endurance run at speeds from 24,000 to 40,000 rpm was successfully completed with no noticeable performance degradation. Successful contamination experiments were performed after completion of 175 hours of the endurance schedule. The contamination experiments were not extensive, but they verified that the design concepts were not unduly sensitive to contaminated fuel. Continued development will be required to establish life capability at the design pressure of 650 psig, but short-term capability was established at outlet pressures up to 600 psig. No major limitations with the basic pump design were found. The 50,000-rpm goal appears to be feasible, but further evaluation at speeds above 40,000 rpm was terminated due to bearing problems in the laboratory speed-increaser system. (Author)