燃烧产物特性对燃气弹射内弹道与载荷的影响研究

为了研究燃烧产物特性对燃气弹射初容室二次燃烧流场、内弹道和载荷的影响,采用Realizable k-ε湍流模型、域动分层动网格技术和有限速率/涡耗散模型,建立包含动边界的初容室二次燃烧流动模型。通过与实验数据对比,验证了燃气弹射模型的有效性。数值研究了燃气发生器喷管入口燃烧产物压力和组分浓度比值对燃气弹射内弹道和载荷的影响,计算得到了满足导弹出筒要求的喷管入口压力和组分浓度比值的变化范围。数值研究表明:随着燃气发生器喷管入口压力的增大,初容室中O2完全消耗的时间变短,导弹出筒时间缩短,出筒速度增加,加速度峰值增大;随着喷管入口CO与H2浓度比值的增大,初容室中O2完全消耗的时间变长,导弹出筒时间延长,出筒速度减小,加速度峰值减小。研究结果为燃气弹射内弹道设计提供了理论基础。

The Influence of Combustion Product Properties on Gas-ejection Interior Ballistic and Load Characteristics

Realizable k-ε turbulence model, dynamic mesh update method and finite-rate/dissipation model are used to establish an initial cavity secondary combustion flow model with missile movement for research on the influence of combustion product properties on gas-ejection secondary combustion, interior ballistic and load characteristics. The effectiveness of gas ejection model is proven by comparing the calculated data with the experimental data. The influences of combustion product pressure in gas generator inlet and component concentration on gas-ejection interior ballistic and load characteristics are analyzed. The variation ranges of inlet pressure and concentration ratio are obtained. The numerical results show that, with the increase in inlet pressure，the times of O₂ exhaustion and the time out of tube decrease, and the velocity out of tube and the acceleration peak value increase. With the increase in the concentration ratio of CO and H₂, the time of O₂ exhaustion increases, the time out of tube is extended, and the velocity out of tube and the acceleration peak value decrease.