商场促销计划.doc

May 11, 2004 DP - 7
REACTING FLOW ENVIRONMENTS BRANCH ELORET
DECOUPLING FLOW & MATERIAL RESPONSE
解耦流及材料反应
• TPS materials not selected at the preliminary design phase – computations should guide this choice
初始设计阶段未选择防热系统材料–计算应引导至此选择
• Assume that the surface is non-conducting and can only re-radiate – adiabatic back wall assumption
假设表面无传导性,只有再辐射性–隔热后墙假设
• Assume that the surface plete bination of atoms reaching it – conservative assumption because maximum heat release can be expected
假设表面促使到达表面的原子完全重组–保守假设从而得出最大散热
• Aerothermal analysis can now be performed with a steady flow assumption at any trajectory point – time discretization
气动热分析只能在稳定流场假设下的任意轨道点进行–时间离散化
•Time discretization cannot be too fine for putations – enormous number putations required
时间离散化不太适用于CFD计算–需要对大量数据进行计算
• Need to supplement putations with engineering methodology of acceptable accuracy – engineering methods are much quicker
需要使用合适精准度的工程学方法补充CFD计算–工程学方法更为快速
May 11, 2004 DP - 8
REACTING FLOW ENVIRONMENTS BRANCH ELORET
ABOUT THIS PRESENTATION 关于此次演示
• To demonstrate bination of CFD and engineering methodology in defining aerothermal environments for TPS design
演示为防热设计所定义的气动热环境下的CFD与工程学方法的结合
• Assumes Earth atmospheric flight – flow medium consists of N2, O2, & products
假设地球大气层飞行–气场至少包含氮气、氧气及其化合物
• Does not call out material choices or sizing
不涉及材料选择及大小
• Uses X-33 flight vehicle as a case study
使用X-33飞行器作为案例研究
• The presentation is not prehensive account of various approaches
此演示非多种方法的综合预计
• The presentation is a focused one – drawn on the experience of a small team at NASA Ames Research Center
此次演示为一次集中演示–由NASA阿姆斯研究中心一个小组经验绘出
May 11, 2004 DP - 9
REACTING FLOW ENVIRONMENTS BRANCH ELORET
REQUIREMENTS – CONFIGURATION
要求–结构
• Since in-depth conduction is neglected, only the outer surface (outer mold line or OML) definition is required
由于已忽略深度传导性问题,此处只要求对外表(外模线,又称OML)做出定义
• Configuration is usually available in some CAD format
在一些CAD公式中可得出结构
• Translation of C