Experimental and theoretical investigation of heat transfer in a gun barrel

The action of the hot and compressed propellant gas flow in the bore behind a projectile on heat transfer into the barrel wall is investigated by experimental and theoretical methods. For theoretical description of the in-bore flow development two interior ballistic models will be applied: a numerical model for solving the full Navier-Stokes equations, and an analytical boundary layer model using the boundary layer equations of Prandtl. For verification the results of both models describing the development of the compressible, turbulent boundary layer at the inner tube wall are compared with heat transfer measurements performed by means of thermocouples in the ISL 20-mm test gun.