Design,Fabrication,and Testing of a Full-Scale Breadboard Nitrogen Generator for Fuel Tank Inerting Application.

摘要

Aircraft fuel tank ullage may contain a mixture of fuel vapor in air that presents a fire and explosion hazard. This hazard can be eliminated if the air is replaced by an inert gas containing insufficient oxygen to allow ignition. Fuel tank inerting systems using onboard storage of liquid nitrogen to supply the inert gas have been demonstrated by the FAA and others and have been retrofitted into some U. S. Air Force transport aircraft. Tests by NAFEC and the Air Force have shown that fuel ullage oxygen concentration must be reduced to 9 percent or less to protect against ignition sources. The use of hollow fiber permeable membranes in an onboard inert gas generator (IGG) fuel tank inerting system has been shown to be a feasible alternative to systems using stored liquid nitrogen, which must be periodically replenished. A program to optimize the permeable membrane geometry; generate data required for system design; and to design, fabricate, and test full-scale breadboard permeable membrane air separation modules was conducted using the McDonnell-Douglas DC-9 aircraft as a design baseline. Results of membrane development, full-scale breadboard module design, and testing are reported; a preliminary design is presented for a hollow fiber permeable membrane IGG system for the DC-9; and ownership considerations for the airborne system design, including a life cycle cost analysis, are discussed. (Author)