One-Dimensional Modeling of Liquid Injection in a Regenerative Propellant Gun.
Abstract
The experimental data from a 30-mm regenerative liquid propellant gun has been analyzed. The injection of the liquid propellant into the combustion chamber is usually modeled as steady state Bernoulli flow with a fixed discharge coefficient. However, the data analysis indicates that the discharge coefficient increases slowly to approximately a steady value. To explain this phenomenon, a series of codes have been developed to model the injection process. These are a zero-dimensional (lumped parameter) model (LPIN), a one-dimensional model (ODIN), and a two-dimensional model (MAGIC). For a simple test problem, the three codes are in reasonable agreement. The two-dimensional code is currently under development, and cannot presently model the large area changes typical of an inline regenerative propellant gun. The zero-dimensional and one-dimensional codes have been applied to an injector resembling that of an actual gun fixture, and agree closely for this case. However, they predict a rapid rise to a steady value. Preliminary indications are that the two-dimensional code will give similar results. The models do not agree well with the data obtained from the experimental gun firings. Once the two-dimensional model is fully functional, the agreement may improve. But it appears that other phenomena not included in the model are important. Keywords: Computational fluid dynamics; Transient flow; Fuel injection; One-dimensional modeling; Discharge coefficient; Liquid flow; regenerative gun.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1988
- Accession Number
- ADA195173
Entities
People
- Terence P. Coffee
Organizations
- Ballistic Research Laboratory