To ensure the safety of aircraft fuel tanks, the FAA issued an airworthiness clause (25.981(b)) suggesting that the risk of combustion and explosion be reduced by installing a Flammability Reduction Means or an Ignition Mitigation Means. The airflow distribution method has a significant effect on the inerting performance. Therefore, this study aims to determine an optimum airflow distribution method of the inerting system.
This paper establishes the calculation model of the oxygen concentration in the ullage of a multi-bay fuel tank, calculates the oxygen concentration in the ullage of an aircraft tank in single-flow and dual-flow modes under series and parallel ventilation methods and analyses the inerting performance of the tank under different airflow distribution methods.
The results show that: (1) the bleed flow rate required to achieve whole process inerting of multi-bay fuel tank in dual-flow mode is lower than that in single-flow mode; (2) under the parallel ventilation method, the decrease of oxygen concentration and the uniformity of each bay are better than that in the series ventilation method; (3) dual-flow mode staged ventilation method can be used to achieve the whole process inerting of the tanks under the minimum engine bleed consumption.
The novelty of this paper is to analyze and optimize the airflow distribution method of the inerting system under the whole flight envelope to minimize the engine bleed consumption.
Improvement of inert-gas distribution for fuel tanks with the objective of minimum bleed flowrate
Aircraft Engineering and Aerospace Technology ; 96 , 6 ; 845-853
2024-08-07
9 pages
Article (Journal)
Electronic Resource
English
DEVICE OF FUEL BLEED FROM TANKS OF SPACECRAFTS UNDER ZERO GRAVITY CONDITIONS
European Patent Office | 2017
|AIR BLEED OBJECTIVE FOR HELICOPTER TURBINE ENGINES
SAE Technical Papers | 1969