Steady Flow Combustion Model for Solid-Fuel Ramjet Projectiles
Abstract
Various solid-fuel ramjet (SFRJ) tubular projectiles have been developed. A spin-stabilized 75mm version has been designed for use as a tank gun training round (TGTR) for the 105mm, M68 tank cannon. Computational efforts aimed at modeling the combustion in the SFRJ are essential to future design modifications and applications of the SFRJ to high-velocity, low drag, anti-tank projectile systems. The steady flow Navier-Stokes equations are written in stream function-vorticity form and solved using a Gauss-Seidel relaxation scheme. A diffusion-flame combustion model is formulated and linked to the Navier-Stokes equations by equations for the conservation of chemical species mass and source terms in the energy equation. Since a steady-state solution is produced, solid fuel ignition and depletion events are ignored. Radiation effects due to combustion are also neglected. The diffusion-flame combustion model assumes a mass-controlled reaction between fuel and oxidizer (air). The reaction occurs in one step and is undirectional. The reaction is diffusion- controlled so that the reaction rate is faster than the diffusion rate. An actual value for the reaction rate is not required since a single equation for the conservation of fuel and oxidizer mass is formulated. The model includes the effects of axial rotation of the combustion chamber. A phenomenological turbulence model is used. Computed solid fuel regression rate and thrust for a solid-fuel ramjet projectile agree well with experimental data and in-flight observations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1989
- Accession Number
- ADA206748
Entities
People
- Michael J. Nusca
Organizations
- Ballistic Research Laboratory