Finite Element Simulation of Effect of Channel Structure on 7-perforated Propellant Extrusion Flow and Mold Optimization Design

摘要

7-perforated propellant is a kind of standard progressive combustion gunpowder which is used in artilleries currently and effectively improves the muzzle velocity. For now, extrusion is a processing technique widely used in multi-perforated propellants produce. The method takes into account several issues namely, holes dislocation, deformation and tow central density. These problems restrict the development of the propellant. In this paper, the fluid in 7-perforated propellant extrusion die is simulated by finite element software. Orthogonal test is carried out to optimize the structure of the mold. The influence of major structure parameters, such as contraction ratio, contraction zone length and forming zone length, on maximum pressure, pressure distribution and velocity distribution in the channel is analyzed by numerical analysis method. In this work, influence degree of structure parameters on the maximum pressure in the channel and on the mold needles, the pressure distribution of forming zone entrance and the outlet velocity distribution is studied, that provides the basis for the 7-perforated propellant mold improving. The result shows that the quality of propellants extruded by the optimized mold is stable.