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In rocket systems, the re-entry speed to atmosphere is very high which leads to compression of air molecules and appearance of strong bow shock waves in the leading edge; consequently, this yields aerodynamic heating. Using ablating-dispensing materials on the leading edge surfaces, it is important to accurately determine heat flux on these moving boundaries. Measuring heat flux directly is very difficult or impossible in some situations. In the present study, the online Kalman filtering is used to determine heat flux accurately. Since the heat flux is estimated in online (non-iterative) fashion, the optimum location of temperature sensors can be effectively determined. In addition, the results of this study can be used to design heat flux sensors. In this paper, the optimum locations of three temperature sensors are calculated on the basis that the disturbances occur due to burning of sensors are reduced. More robust solutions are obtained for heat flux on the ablating surfaces.

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In this paper, an inverse analysis of combined radiation and convection heat transfer in a 2-D rectangular duct is presented. The working fluid is a mixture of air including CO2 and H2O as two radiating gases. The purpose is to verify the effects of gas mole fractions on the solution of inverse design problem in which the conjugate gradient method is used to find the temperature distribution over the heater surface to satisfy the prescribed temperature and heat flux distributions over the design surface. The radiating gas is considered to be a gray participating medium with absorption, emission and isotropic scattering. The Planck mean absorption coefficient is calculated and used in radiative calculations. The discrete ordinates method is used to solve the radiative transfer equation. An attempt is made to determine the temperature distributions over the heater surface while the enclosure is filled with different mole fractions of CO2 and H2O. The effects of other parameters such as radiation conduction parameter on the solution of inverse problem is examined.

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In orthopedic surgery, the drilling process is used to internally fix the fracture zone. During bone drilling, if the temperature exceeds the limit of 47 °C, it results in altered bone alkaline phosphatase nature, occurrence of thermal necrosis, non-fixation and inadequate bone fusion In order to investigate the effective parameters of the drilling process, after three-dimensional modeling of the femur bone in Mimics software and determination of bone coefficients based on the Johnson-Cook model, numerical simulation of the cortical and trabecular bone oblique drilling process have been performed. The drilling process was performed in both normal and high speed modes based on reverse heat transfer theory using DEFORM-3D software. The results of numerical simulation after validation with experimental results showed that this theory is capable of estimating the temperature and heat flux in this process and the occurrence of necrosis in both processes (normal and high speed) is imminent. The temperature in the drilling area of the trabecular bone is higher than the cortical bone at all speeds and feed rates and the axial force of the trabecular bone is less than the cortical bone at all speeds and feed rates. The optimum point leading to the minimum temperature in normal drilling of trabecular and cortical bone is the feed rate of 150 mm/min and the rotational speed of 2000 rpm. This optimum point is obtained in the high-speed drilling of trabecular and cortical bone at the feed rate of 150 mm/min and rotational speed of 4,000 rpm and 7,000 rpm.