Development of a Retractable Vane Starting Pump Integrated within a Vapor Core Fuel Pump. Turbine Engine Technology Demonstrator Component Development Program, Project 668A. Controls Development Program (Part 5).

This report documents a conceptual development program, the bulk of which was performed by Chandler-Evans Controls Systems Division of Colt Industries as sub-contractor to the Detroit Diesel Allison, Div. of GMC. This Air Force funded program demonstrates the feasibility of integrating a starting fuel pump with an existing centrifugal pump to serve as a main engine fuel pump for a joint technology demonstrator turbofan engine. A retracting vane concept was designed to provide starting fuel flow up to a speed where the vanes retract and the vapor core pump takes over. An inlet throttle valve controls pump output to meet engine demand. The combined pump was fabricated and tested at all speeds up to and including max speed of 28000 rpm and met light off, transition and max flow and pressure requirements. Weight and cost estimates are 50% of present-state-of-the art pumps. This report contains detailed design information and preliminary test results that dictated redesign and the final successful test results. In addition to favorable cost and weight estimates, appreciable reduction of fuel heating is demonstrated due to its inlet throttled non-bypassing operating mode. (Author)