Mathematical modeling of hydrogen fuel for advanced airbreathing jet propulsion simulations

The versatile QNEP (Quick Navy Engine Program) has been extended to allow treatment of advanced airbreathing jet propulsion engines using hydrogen or hydrocarbon fuels. This modification of the engine code has been exercised for turbofan, augmented turbofan, and ramjet engines using both hydrogen and hydrocarbon fuels.

Examination of modified QNEP (denoted MNEP) thermodynamic routine performance and comparison of this performance with other standard references have been presented. This includes combustion temperature rise for air-hydrogen combustion, air-hydrocarbon fuel combustion, and air thermodynamic properties.

This code can include or preclude the effect of dissociation in the engine cycle performance evaluation. It can also treat the gas mixture as frozen or equilibrium flow through the nozzle. A listing of the MNEP program is included.

Recommendations have been included for the study of the overall merits of hydrogen and hydrocarbon fueled engines and incorporation of analytical models of additional turboaccelerator features in the MNEP code.