To analyze the effect law of die structure parameters in extrusion forming process on the swell ratio and flow uniformity of seven-perforation nitroguanidine gun propellant, the extrusion forming process was simulated by computational fluid dynamic method, the primary and secondary relationship of die structure parameter importance was discussed, the die structure for seven-perforation gun propellant was optimized and experimental validation was performed.The results show that the influence of contraction angle of die on the swell ratio and uniformity of dough exit velocity is the biggest, the compression section height is secondary and the forming section length is smallest.The uniformity of velocity distribution at the flow channel exit end after optimization of die is improved by 36.53%, indicating the reliability and practicability of the simulation calculation.%为了分析挤出成型过程中模具结构参数对七孔硝基胍发射药离模膨胀率及流动均匀性的影响规律,采用计算流体力学方法,对挤出成型过程进行模拟计算,讨论了模具各结构参数重要性的主次关系;对七孔发射药制备模具进行了结构优化,并进行了实验验证.结果表明,模具收缩角对膨胀率和药料出口速度均匀性的影响最大,压缩段高度次之,成型段长度的影响最小.模具优化后流道出口端速度分布均匀性提高36.53%,表明该模拟计算的可靠性与实用性.
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