COMPUTATIONAL STUDY OF THE FLOW AROUND A PROJECTILE MOVING THROUGH A GUN BARREL

摘要

Computation of the flow field around a projectile moving through a gun barrel is a complex problem. The complications are due to presence of numerous factors, such as turbulence, compressibility, anisotropy of the stress field, complexities due to surface geometry, and change of the computational domain in time. In this study, calculation of the flow characteristics around 155 mm moving projectile in gun barrel is undertaken. The flow is considered to be unsteady, compressible, turbulent, and nonisothermal. An anisotropic two-equation model for the Reynolds stress that was developed through a novel technique involving the representation of the energy spectrum and invariance based scaling is used in performing calculations. The model was implemented in a commercial code (Fluent) and its performance was validated with benchmark experimental flows. Computations are performed for stagnation pressures of up to 600 Mpa, temperatures of up to 5000K, and free-stream velocities of about 1000 m/s in this study. The results are analyzed and the predictive capability of the model is discussed.