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Numerical analysis of semiconductor thermocouple operation in recording exothermic processes in a recovery capsule




 The γray altimeter, containing a γradioactive source 137 Cs with activity of 2.96 ×10 10 Bq,was used to detect the height of the spacecraft recovery capsule during landing.To measure the γdose distribution near to the guidance section, especially at position where the useful load is located in recovery capsule,γdose field at the testsite for one machine test was measured by means of a γdose rate meter FJ317C and a γdose meter AHPИ0102. The result showed that the absorbed... The γray altimeter, containing a γradioactive source 137 Cs with activity of 2.96 ×10 10 Bq,was used to detect the height of the spacecraft recovery capsule during landing.To measure the γdose distribution near to the guidance section, especially at position where the useful load is located in recovery capsule,γdose field at the testsite for one machine test was measured by means of a γdose rate meter FJ317C and a γdose meter AHPИ0102. The result showed that the absorbed dose rate at 5 meters from γsource on the ground is as low as the radiation protection limit when the altimeter is down to 0.16 m from the ground.The ground reflection effect for γray decreases as height of the recovery capsule increases. Therefore, the γdose level at useful load in the recovery capsule will meet the requirements of flight safety.  γ射线高度计用于航天器回收舱回收着陆过程中的近地高度测量。其内装有活度为２．９６×１０１０Ｂｑ的１３７Ｃｓγ放射源。为了解仪表舱附近，特别是回收舱内有效载荷所在处的γ剂量分布，利用ＦＪ－３１７Ｃ＿γ剂量率仪和ＡＨＰИ－０１－０２γ剂量率仪对单机试验现场的γ剂量场进行了测量。结果表明，当高度计下降到距地面０．１６ｍ时，地面上距γ源５ｍ处的吸收剂量率低于辐射防护限值。随着回收舱高度的增加，地面对γ射线的反射作用将下降。因此，回收舱内有效载荷处的γ剂量率水平将满足安全飞行的要求。  A numerical simulation of sub_tranconic and hypersonic flow fields over recovery capsule is studied by solving Euler equations and Navier_Stokes qeuations. The Euler equations are solved by Second Order Godunov Limited Volume Method. Harten_Yee/TVD scheme is applied to solve the Navier_Stokes equations. The surface pressure distributions, aerodynamic coefficients, flow features including shock wave, flow separation and vortex are obtained by using above numerical procedure for capsule in different... A numerical simulation of sub_tranconic and hypersonic flow fields over recovery capsule is studied by solving Euler equations and Navier_Stokes qeuations. The Euler equations are solved by Second Order Godunov Limited Volume Method. Harten_Yee/TVD scheme is applied to solve the Navier_Stokes equations. The surface pressure distributions, aerodynamic coefficients, flow features including shock wave, flow separation and vortex are obtained by using above numerical procedure for capsule in different range of speed. Moreover, the numerical results agree well with those of experiments. Through analyses for the numerical results of flow_field of perfect air, equilibrium and Non_Equilibrium air, this thesis demonstrates that the influence of real air effects on the aerodynamics characters of the capsule is not significant. The numerical results illustrated that the numerical simulation is an effective tool to predict aerodynmic characters capsule.  文章基于Euler方程及N_S方程的数值求解方法 ,对返回舱亚、跨声速和高超声速的流场及气动特性进行了数值模拟 ,其中Euler方程数值求解采用二阶Godunov有限体积法 ;N_S方程数值求解采用二阶Harten_Yee格式的差分法。得到同实验值一致的物面压力、气动力系数和在不同速度范围出现的激波、流动分离及旋涡等流场特征。通过完全气体、平衡气体和非平衡气体的流场数值模拟结果分析比较 ,得出真实气体效应对返回舱气动力特性影响较小这一结论。计算结果表明数值模拟方法是预测返回舱气动特性的有效手段  >=A dose rate calculation of a γray altimeter in ShenZhou spacecraft recovery capsule was studied with Monte Carlo methods.According to experimental measurement data,the structure of theγray altimeter is decided to be a cylinder with the radius of 4.5 cm and 6.0 cm height with inversive Monte Carlo calculation.The model of the recovery capsule is built under the description of the newspaper with a parabola shape superstructure and a cylinder bottom.The height of the recovery capsule is 2.8... >=A dose rate calculation of a γray altimeter in ShenZhou spacecraft recovery capsule was studied with Monte Carlo methods.According to experimental measurement data,the structure of theγray altimeter is decided to be a cylinder with the radius of 4.5 cm and 6.0 cm height with inversive Monte Carlo calculation.The model of the recovery capsule is built under the description of the newspaper with a parabola shape superstructure and a cylinder bottom.The height of the recovery capsule is 2.8 m,the diameter of the bottom is 2.25 m and the height of the bottom is 0.5 m.Theγray altimeter is installed in the center of the bottom.A mathematical male phantom with the data of Chinese Reference Man was placed into the capsule.The phantom is 1.70 m height and 60.0 kg weight.24 kinds of different organs and tissues are identified in the phantom,including 13 types of skeletons.Using these models in Monte Carlo method,the dose rate of organs and tissues are calculated.It shows that in 10 g/cm2 aluminum shielding structure,the dose rate of theγray altimeter is equivalent to space radiation dose rate as 4 μGy/h.  A dose rate calculation of a γray altimeter in ShenZhou spacecraft recovery capsule was studied with Monte Carlo methods.According to experimental measurement data,the structure of theγray altimeter is decided to be a cylinder with the radius of 4.5 cm and 6.0 cm height with inversive Monte Carlo calculation.The model of the recovery capsule is built under the description of the newspaper with a parabola shape superstructure and a cylinder bottom.The height of the recovery capsule is 2.8 m,the diameter of... A dose rate calculation of a γray altimeter in ShenZhou spacecraft recovery capsule was studied with Monte Carlo methods.According to experimental measurement data,the structure of theγray altimeter is decided to be a cylinder with the radius of 4.5 cm and 6.0 cm height with inversive Monte Carlo calculation.The model of the recovery capsule is built under the description of the newspaper with a parabola shape superstructure and a cylinder bottom.The height of the recovery capsule is 2.8 m,the diameter of the bottom is 2.25 m and the height of the bottom is 0.5 m.Theγray altimeter is installed in the center of the bottom.A mathematical male phantom with the data of Chinese Reference Man was placed into the capsule.The phantom is 1.70 m height and 60.0 kg weight.24 kinds of different organs and tissues are identified in the phantom,including 13 types of skeletons.Using these models in Monte Carlo method,the dose rate of organs and tissues are calculated.It shows that in 10 g/cm2 aluminum shielding structure,the dose rate of theγray altimeter is equivalent to space radiation dose rate as 4 μGy/h.  
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