横風を受ける水素噴流拡散火炎の形状に関する特性〔熱工学, 内燃機関, 動力など〕

抄録

The combustion characteristics of hydrogen jet diffusion flames on a flat plate in a cross flow were studied experimentally and two distinct types of hydrogen jet diffusion flames were observed. The first type was the hole opening flame, which had a hole on the front side of the flame at the transition point from laminar to turbulent flow. It was found that the turbulence intensity was suddenly increased at the lowest position of the hole. The hole opening phenomenon may be explained by the mass and heat transfer rate exceeding the finite chemical reaction rate of hydrogen with air. As the hydrogen injection velocity increased, the hole opening flame changed to the second type of flame. This was a stick flame which formed along the recirculation zone of the hydrogen jet acting on the cross flow as a "rod". Detailed observations showed that a premixture was formed in a mixing layer between the hydrogen jet and the surrounding cross air flow, and it burned just behind the hydrogen jet.