Technical Paper
Mechanism of Deposit Formation in Wing Tanks
1968-02-01
680733
Deposits form in the “empty” wing tank environment as a result of a complex autoxidative degradation of the hydrocarbon fuel. For the past two years, Esso Research and Engineering Co. has been carrying out a fundamental study for the Air Force of the variables which control such deposit formation. Extensive studies have been carried out in a specially designed apparatus which simulates the kinetic environment found in a wing tank. Independent Advanced Aircraft Fuel System Simulator studies have shown that this apparatus is the only small test apparatus currently available which accurately rates the wing tank deposit formation tendency of jet fuels. Rigorous exclusion of oxygen has been demonstrated to eliminate deposit formation at temperatures up to 500 F. The rate of deposit formation from typical jet fuels exhibits a 10 kcal/mole apparent activation energy and a 0.2 order in oxygen partial pressure at moderate oxygen partial pressure levels.