Numerical simulation of a connected-pipe test ramjet motor

Resumo

This work presents both analytical and numerical simulations of a ramjet engine developed at the Chemical
Propulsion Laboratory (CPL) of the University of Brasilia (UnB) to aid its design and safety for future hot tests.
The test facility comprises a connected-pipe test bench with a heater simulating the diffuser flow. The test bench’s
primary objective is to study the ramjet combustion chamber performance and the cooling wall effect provided by
the presence of the flame holders. Transient time-averaged Navier-Stokes equations in two-dimensional form and
the k− turbulence model describe the flow behavior. The non-premixed model based on GriMech 3.0 mechanism
takes into account chemical transformations. Implementation of the structured mesh and mesh sensitivity analysis
yielded optimal simulation accuracy and time. The numerical simulation studies the motor performance in three
flight regimes. The validation of the simulation results to analytical and numerical ones presented an acceptable
level of data conformity. As a main result, CFD simulations proved the ramjet wall cooling concept with an efficient
flame holder and separator. Consequently, more advanced simulations will be provided in the future resulting in
recommendations for hot tests.