热量损失和气相凝结对电爆阀建压影响研究

为了研究爆炸燃气热量损失和气相产物凝结对电爆阀建压过程的影响,在一维半无限平板对流传热模型的基础上建立了一种简单的气相凝结仿真模型,预估的铝/高氯酸钾电爆管密闭爆发器试验曲线基本符合试验结果。基于仿真模型研究了铝/高氯酸钾电爆阀建压阶段对流传热和气相氯化钾凝结受传火孔影响的机理。结果表明:建压阶段燃气流动加剧了壁面对流传热和气相凝结,从而导致压力损失严重,传火孔直径越小影响越显著。对于采用金属粉末/高氯酸钾作为输出药的电爆阀,均应避免小传火孔结构。

Effects of Heat Loss and Gas Condensation on Pressurization in Pyrovalves

A simple gas product condensation model was developed on semi-infinite wall convective heat transfer model,to simulate the influence of heat loss and condensation of condensable gas-products on pressurization in pyrovalves.The model was used to simulate the interior ballistics of aluminum/potassium perchlorate cartridge closed bomb tests,which approves that heat loss and gas phase condensation is one of the main reasons for that the pressure decreases rapidly.Then the processes of convective heat transfer and condensation of potassium chloride vapour influenced by port in a normally-closed pyrovalve were predicted,which indicates that,gas flow enhances convective heat transfer and gas condensation during the pressurization period,which results in considerable pressure loss and turns more grievous with smaller port.So small port structures should be avoided in the pyrovalves that use metal powders/potassium perchlorate as main charges.