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 The heat conductive equations of coat and substrate materials under laser beam radiations are solved using the method of integral transformation, and the 3D temporal distribution of temperature is given under the some approximations. A numerical analysis is given for CrZG 45 steel as an example .  本文采用积分变换法求解了在激光束辐照下涂层和基体材料中的热传导方程,并在一定的近似条件下,给出了温度场的三维、瞬时分布。以Cr—ZG45钢系统为例,进行了数值分析。  The reentry thermoprotection problem of space shuttle was solved mainly through wellconducted experiments. Chinese engineers now find it feasible and more efficient to supplement experiments with theoretical analysis. This paper presents a method for calculating ablative rate and internal temperature distribution of CC nose cap of space shuttle. Theoretical analysis of CC nose cap must overcome two main difficulties. These two difficulties are: 1)Heatconduction is under moving boundary condition.... The reentry thermoprotection problem of space shuttle was solved mainly through wellconducted experiments. Chinese engineers now find it feasible and more efficient to supplement experiments with theoretical analysis. This paper presents a method for calculating ablative rate and internal temperature distribution of CC nose cap of space shuttle. Theoretical analysis of CC nose cap must overcome two main difficulties. These two difficulties are: 1)Heatconduction is under moving boundary condition. With aerodynamic heating, the ablative consumption of material causes the thickness of thermoprotective layer to become thinner and thinner, resulting in continuously changing of heatconduction pattern from body surface into its interior. Thus, heatconductive calculation should take into account the rather difficult problem of moving boundary. 2)With aerodynamic state and thermoprotectiv material previously determined, wall temperature is the decisive factor influencing ablation, but wall temperature itself is much influenced by the heat conducted to structure. On the other hand, the degree of severity of ablation affects not only thermoeffect terms but also the speed of motion of moving boundary and consequently heatconduction. In other words, ablation and heatconduction are coupled, and this presents considerable difficulty which must be overcome in theoretical analysis. Besides, material anisotropy and physical properties that change with temperature also make calculations more difficult. In this paper, we establish equations of ablative outline and ablative rate on the basis of aerodynamicthermochemical model, employ energy balancing method to establish transient heatconductive equation that takes into account anisotropy and changing physical properties, treat properly the ablative moving boundary through coordinate transformation, and finally, successfully carry out the solution of coupled ablation and heatconduction. Calculated distributions of ablative rate and temperature in CC nose cap of shuttle are presented in Figs. 3(b) through . Preliminary tests indicate that our method of calculation shows good promise for perfecting calculations that are in agreement with experimental data.  本文对航天飞机机头的碳碳热防护层,在再入的气动加热条件下,采用气动热化学烧蚀模型建立烧蚀方程,采用单元体能量平衡法建立各向异性、变物性材料的瞬态热传导方程,通过坐标变换处理烧蚀移动边界,并从物理平面转换到计算平面中去,然后成功地进行了烧蚀和温度场的耦合求解。计算结果表明了航天飞机机头碳碳热防护层中的烧蚀和温度分布规律。  Basing on thermal interaction between laser and organization, we discussed the mechanism,and utilize heat conductive equation to describe it guantitatively. An evidence of clinical applications of laser acupuncture and moxibustion are obtained.  从激光对穴位组织的热作用，探讨激光针灸的作用机理，利用能量守恒建立穴位组织的热传导微分方程，对针灸作用作量化描述，为激光针灸的临床治疗提供理论基础。   << 更多相关文摘 
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