One-dimensional simulations of jet fuel thermal-oxidative degradation and deposit formation within cylindrical passages

Flowing aviation fuel is used as a coolant in military aircraft, Dissolved O-2 reacts with the heated fuel to form undesirable surface deposits which disrupt the normal flow. For purposes of aircraft design, it is important t o understand and predict jet fuel oxidation and the resulting surface depos ition. Detailed multi-dimensional numerical simulations are useful in under standing interactions between the fluid dynamics and fuel chemistry. Unfort unately, the detailed simulation of an entire fuel system is impractical. O ne-dimensional and lumped parameter models of fluid dynamics and chemistry can provide the simultaneous simulation of all components which comprise a complex fuel system. In this work, a simplified one-dimensional model of je t fuel oxidation and surface deposition within cylindrical passages is deve loped. Both global and pseudo-detailed chemical kinetic mechanisms are used to model fuel oxidation, while a global chemistry model alone is used to m odel surface deposition. Dissolved O-2 concentration profiles and surface d eposition rates are calculated for nearly isothermal and nonisothermal flow conditions. Flowing experiments are performed using straight-run jet fuels , and the predicted dissolved O-2 concentrations and surface deposition rat es agree reasonably well with measurements over a wide range of temperature and flow conditions The new, model is computationally inexpensive and repr esents ct practical alternative to detailed multi-dimensional calculations of the flow in cylindrical passages. [S0195-0738(00)01204-8].