激波喷出过程和在林带中的传播  

Shock Ejection from a Tube and Propagation in Forest Belt

作　　者：常熹钰[1] 易仕和[1] 罗俊荣 周勇为[1] 文定元[2] 邓湘雯[2] 

机构地区：[1]国防科技大学航天技术系,湖南长沙410073 [2]中南林学院资源环境系,湖南株洲412006

出　　处：《爆炸与冲击》2000年第4期373-378,共6页Explosion and Shock Waves

基　　金：国家自然科学基金项目!( 39770 62 3)

摘　　要：运用激波管技术研究了激波从管口喷出和在林带中传播这两个基本问题。给出了三方面的结果 :揭示了激波从管口喷出时的复杂流场 ,显示了主激波弯曲和衰减 ,二次激波的形成和合拢 ,涡环的长大和发展 ,以及涡环前缘出现正激波等基本物理现象 ;显示了激波在林带中的传播过程 ,取得了激波遇林地的反射 ,马赫杆形成 ,激波与林冠的相遇 ,林冠对涡环的阻滞效应等纹影照片 ;沿激波在林地的传播方向测量了地面压力 ,证实林带有明显的消波效应。The diffra ction process produces a very complex flow fi eld when a moving shock wave emerges fro m the open end of a shock tube.In this p aper,the experiments by using a shock tu be and its primary results are presented .Two basic problems are considered:the s hock wave ejecting from a tube and propa gating in forest belt.The experimental r esults are:1.The complex flow field intr oduced by the shock wave ejecting from a tube was observed,such as the curvature and attenuation of primary shock wave,t he formation and joint of the secondary shock wave,the growth and development of the vortex rings,the occurrence of norm al shock wave in front of the vortex rin gs and so on.2.The propagation process o f a shock wave in the forest belt is sho wn on photographs,such as the shock wave reflection on the forest,the formation of Mach stem,the intersection of a shock wave with the forest crown,the obstruct ion effect of the forest crown and so o n .3.The ground pressure along the propaga tion direction of a shock wave was measur e d;the results show that the wave elimina tion effect of the forest belt is very o bvious.

关 键 词：森林 模拟 激波传播 激波喷出过程 林火 灭火 

分 类 号：O354.5[理学—流体力学] S762.3[理学—力学]