自然通风下的高压氢气泄露扩散特性

High-pressure Hydrogen Leakage and Diffusion Characteristics under Natural Ventilation

氢能技术备受全球关注,被誉为21世纪发展前景最为广阔的二次能源之一。然而,随着氢燃料汽车的广泛使用,车库等密闭空间内发生高压氢气泄漏事故的风险也随之增加。由于这种事故的多样性,尤其是高压氢气泄漏在密闭空间内的扩散特性的复杂性,因而需要进一步研究和探讨这一问题。为解决密闭空间内高压氢气泄漏的安全问题,采用了数值计算和理论分析相结合的方法,分析了不同自然通风条件下空间内氢气的通风情况,总结了氢气在空间内的扩散和分布规律。主要结论如下:在自然通风条件下,通风口的长宽比越接近1,通风效果越好;将通风口布置在长边的中心位置,效果也更佳;通风口面积增大对氢气扩散影响不大,但在一定范围内增大通风口的面积,会使得高压氢气扩散的初期更加紊乱;提高通风口的高度对提高通风效果作用显著,将通风口高度从0.5m升高到2.5m,相同时间、位置处的氢气体积分数能降低10%左右。研究了高压氢气在受限空间内的扩散特性及参数,研究结果可为氢能技术在受限空间内的安全设计和措施提供参考。

Hydrogen energy technology has attracted global attention and is known as one of the secondary energy sources with the broadest development prospects in the 21st century.However,with the widespread use of hydrogen-fueled vehicles,the risk of high-pressure hydrogen leakage accidents in confined Spaces such as garages increases.Due to the diversity of such accidents,especially the complexity of the diffusion characteristics of high-pressure hydrogen leakage in a confined space,this problem needs to be further studied and discussed.In order to solve the safety problem of high-pressure hydrogen leakage in confined space,this paper adopts the method of combining numerical calculation and theoretical analysis to analyze the ventilation of hydrogen in space under different natural ventilation conditions,and summarizes the diffusion and distribution law of hydrogen in space.The main conclusions are as follows:under natural ventilation conditions,the closer the aspect ratio of the vent is to 1,the better the ventilation effect is;The air vent is arranged in the center of the long side,the effect is better;The increase of vent area has little effect on hydrogen diffusion,but the increase of vent area within a certain range will make the initial stage of high-pressure hydrogen diffusion more chaotic.Increasing the height of the vent has a significant effect on improving the ventilation effect.When the height of the vent is increased from 0.5m to 2.5m,the volume fraction of hydrogen at the same time and position can be reduced by about 10%.In this paper,the diffusion characteristics and parameters of high-pressure hydrogen in confined space are studied.The research results can provide references for the safety design and measures of hydrogen technology in confined space.