圆筒形容器内可燃气体爆燃过程的数值模拟

NUMEROUS SIMULATIONS OF FLAMMABLE GAS DEFLAGRATIONS IN CYLINDRICAL VESSELS

大型密闭容器内可燃气体爆燃的火焰速度存在着一个加速过程 ,压力也不是均匀分布的。根据密闭容器内可燃气体爆燃的实际情况 ,从流体力学和化学反应动力学出发 ,利用一步不可逆化学反应模型处理能量的加入过程 ,通过高精度的差分格式和时间分裂方法 ,对弱点火条件下密闭容器内可燃气体爆燃的压力场、温度场和浓度场进行了数值模拟 ,并进行了圆筒形容器内可燃气体爆炸实验。结果表明 ,最大爆炸压力和最大压力上升速率均与初始压力呈正比。最大压力及其上升速率在燃料组分化学计量浓度的 1.1倍左右达到最大值。数值模拟计算结果与实验结果比较 ,其偏差不超过 10 %。

The flame velocity of flammable gas deflagration in a large closed vessel has an accelerating process, and the pressure distribution is not homogeneous. According to the real situation of flammable gas deflagration in a closed vessel, based on the fluid dynamics and chemical reaction dynamics , using the adding process of model processing energy of one-step irreversible chemical reaction, with high accurate differential pattern and time split method, the numerous simulation is carried out for the temperature, pressure and concentration fields in a closed vessel under weak firing conditions. And the explosion tests of flammable gas in cylindrical vessels are conducted. The results show that the maximum explosion pressure and the maximum pressure rising rate are proportional to the initial pressure. The maximum explosion pressure and the maximum pressure rising rate reach their extreme values when about 1.1 times of chemical measured concentration of the fuel components. Comparing with the experimental results, the deviations of calculated results are within 10%.