论文部分内容阅读
氢气从高压储存系统的泄漏将在出口外形成高压、欠膨胀射流,并形成被称为马赫盘的激波结构.本文利用二维轴对称几何模型模拟了储存压力为10 MPa和20 MPa的高压氢气通过直径为1 mm的小孔向周围环境泄漏的问题,并与理论计算结果和实验数据进行了比较.模拟结果表明:由于存在黏性阻力,气流通过马赫盘后的速度低于理论计算的速度,马赫盘下游沿径向的气流参数分布并不均匀.氢气沿射流中心线的浓度分布与实验数据基本吻合.模拟还得到了不同滞止压力下氢气的最低可燃轮廓和泄漏出口外的危险区域范围.“,”Hydrogen leakage from high pressure storage systems will result in high pressure,under-expanded jets outside the exit with a shock wave structure called the Mach disk.High pressure hydrogen releases with storage pressures of 10 MPa and 20 MPa into the surrounding ambient through a small orifice of 1 mm diameter are numerically studied using a 2D axisymmetric model.The numerical results are compared with theoretical calculations and experimental data.The results show lower velocities and non-uniform profiles of the flow parameter distributions after the Mach disk compared with the theoretical results due to the viscous resistance.The hydrogen concentrations along the jet centerline compare well with the experimental data.The simulations also predict the flammability envelopes and hazardous zones for a range of stagnation pressures.