期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
精准定需 以需导教
1
作者 张岸刚 《作文成功之路(中考冲刺)》 2018年第11期25-25,共1页
语文教学要实现最大化,就要精准定位学生的需求,以学生的需求来确定语文教学具体内容。在具体的教学中,教在缺失处、教在易混处和教在疑难处是以需导教的三种重要形式。
关键词 定位 需求点 缺失 易混处 疑难
下载PDF
Numerical simulation for explosion wave propagation of combustible mixture gas 被引量:2
2
作者 王成 宁建国 马天宝 《Journal of Central South University of Technology》 EI 2008年第3期361-367,共7页
A two-dimensional multi-material code was indigenously developed to investigate the effects of duct boundary conditions and ignition positions on the propagation law of explosion wave for hydrogen and methane-based co... A two-dimensional multi-material code was indigenously developed to investigate the effects of duct boundary conditions and ignition positions on the propagation law of explosion wave for hydrogen and methane-based combustible mixture gas. In the code,Young's technique was employed to track the interface between the explosion products and air,and combustible function model was adopted to simulate ignition process. The code was employed to study explosion flow field inside and outside the duct and to obtain peak pressures in different boundary conditions and ignition positions. Numerical results suggest that during the propagation in a duct,for point initiation,the curvature of spherical wave front gradually decreases and evolves into plane wave. Due to the multiple reflections on the duct wall,multi-peak values appear on pressure-time curve,and peak pressure strongly relies on the duct boundary conditions and ignition position. When explosive wave reaches the exit of the duct,explosion products expand outward and forms shock wave in air. Multiple rarefaction waves also occur and propagate upstream along the duct to decrease the pressure in the duct. The results are in agreement with one-dimensional isentropic gas flow theory of the explosion products,and indicate that the ignition model and multi-material interface treatment method are feasible. 展开更多
关键词 combustible mixture gas explosion wave interface treatment combustion function mode
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部