- Author
-
Bonnell, J. W.
|
Vranos, A.
- Title
- Theoretical Study of Combustion Stability in an Air-Liquid Fuel Combustion Zone.
- Coporate
- Pratt and Whitney Aircraft, East Hartford, CT
- Keywords
-
combustion stability
|
liquid fuels
|
burning rate
|
equations
- Identifiers
- jet engine burner
- Abstract
- A linearized analysis is performed to determine the conditions for either stable or unstable combustion in the primary combustion zone of a jet engine burner. The combustion system analyzed consists of liquid fuel droplets burning in air; part of the primary air flows into the control volume from ports in the chamber wall. The burning rate is governed by a droplet vaporization rate-controlled mechanism. The system of conservation equations is perturbed by a longtidudinal pressure disturbance. The resulting perturbation equations are linearized and combined to form wave equations for the pressure and velocity distrubances. The stability characteristics of the system are determined from the sign and magnitude of the damping (or amplification) coefficient in the wave equation. Trends toward stable or unstable combustion are determined for changes in operating and flow conditions, vaporization rate parameters, and primary air injection parameters.