Project Title:

Acoustic Interactions with Spray Combustion in Liquid Propellant Rocket Thrust Chambers

92-1-11.03-6576                                                   NAS08-39813
Acoustic Interactions with Spray Combustion in
     Liquid Propellant Rocket Thrust Chambers
CFD Research Corporation
3325-D Triana Boulevard
Huntsville, AL  35805
Maciej Pindera                                       (205-536-6576)

Abstract:

     Combustion instabilities in liquid rocket motors result from
complex, transient, nonlinear interactions between gas flow,
pressure waves, and processes associated with heat release. Recent
developments in numerical technology, allow for viable simulations
of these interactions. The current numerical models for combustion
instability, however, do not make use of available highly accurate
schemes. This project will develop a high accuracy numerical model
capable of resolving nonlinear interactions among liquid fuel
sprays, fluid dynamics, and chemistry, and understanding their
effects on combustion instabilities in the rocket motor environ-
ment. Phase I will concentrate on the coupling between spray
characteristics and droplet transport, using simple chemistry in a
two-and three-dimensional compressible flow field. After the flow
field has been calculated using highly accurate TVD or Godunov
schemes, it will be tested and made available at the company.
Spray physics will include a correlation type spray model coupled
to existing unsteady droplet evaporation and Lagrangian tracking
algorithms. Simulations will be performed to study the response of
combustion to different spray configurations. This research will
result in an advanced multi-dimensional combustion instability
code that can be used by NASA to design future rocket thrust
chambers and predict combustion stability limits.

Potential Commercial Application:

Potential Commercial Applications:  This project will produce an
advanced numerical methodology for studies of nonlinear combustion
instabilities in liquid rocket engines. The developed computer
code will be of interest to all injection spray designers and
rocket chamber manufacturers where accurate simulations of
acoustically coupled flow transients is of paramount importance.

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