The Studies of Shock Wave Structure of the Release from High Pressure Hydrogen

• Main Authors: Sin-Ying Wu, 吳信穎
• Other Authors: Jenq-Renn Chen
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/37158371904471043463

碩士 === 國立高雄第一科技大學 === 環境與安全衛生工程研究所 === 99 === In recent year, the development of alternative energy such as solar, biomass, hydrogen, etc. has been growing significantly in each country owing to the increasing global warning and energy issues. Among these, hydrogen is a clean energy carrier with high energy-conversion efficiency, low pollution and producing no greenhouse effect. It is also widely used in petrochemical, semiconductor, optoelectronics and other industries. However, hydrogen has a very wide explosion limit (4% to 75%), and is a highly hazardous flammable gas. Although hydrogen is not a pyrophoric gas, it may ignite under certain high-pressure release conditions. Current literatures on the ignition mechanism and condition remain unclear. It is generally suggested that it is shock wave generated from the release that heated the air/hydrogen interface caused the ignition. This study designed a hydrogen release control and measurement system to test the release in a rectangular duct at specific pressures. A high pressure solenoid valve is used to control the release to ensure a consistent release. A high-speed video camera and a shadowgraph system are used to visualize the shock wave structure inside and outside the test duct. The results showed that shock wave propagation was observed for the high-pressure hydrogen release tests in the smallest duct diameter and some particular pressure but not in larger duct diameter tests. It is clear that shock waves generation is strongly related to the duct diameter and the pressure. This result should help to better understand the ignition mechanism, benefit the design and operation in hydrogen related industries, and prevent future incident from occurring.