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Fluid–thermal–structural interactions in hypersonic flows is an extremely complex coupling problem, which puts forward higher requirements on the coupling calculation method and computational effic...

Latent heat storage has proved to be an effective means for thermal management for spacecraft due to its high storage capacity and small temperature variation from storage to retrieval. Although pa...

An improved method for reconstructing internal transit temperature distribution in a heat material is presented in this paper. This method combines the advantages of the ultrasonic measurement and inverse analysis. Firstly, a numerical model of sensing interior temperature field is obtained based on temperature dependence of the velocity of ultrasonic wave (acoustic velocity) propagating through heated materials. Then, an inverse analysis by the sensitivity method for estimating equivalent thermal boundary conditions are developed to determine the non-uniform temperature fields. Experiments are referred to validate the feasibility and reliability of the presented method, whose robustness and accuracy is also analyzed through a comprehensive parameter analysis. Numerical results reveal that internal temperature gradient and its variation estimated by the developed method agree well with the measured values using thermocouples installed in the steel. Besides, this method can be helpful for solving the problems of transient state boundary using the quasi-steady approximation. It demonstrates that the method presented in this work is a promising means for high-accurately determining internal transient temperature distributions in heat materials by ultrasonic pulse-echo measurements.

The theories of heat transfer, thermodynamics and fluid dynamics are employed to develop the coupled heat transfer analytical methods for the heat-pipe-cooled thermal protection structure (HPC TPS), and a three-dimensional numerical method considering the sonic limit of heat pipe is proposed. To verify the calculation correctness, computations are carried out for a typical heat pipe and the results agree well with experimental data. Then, the heat transfer characteristics and limitations of HPC TPS are mainly studied. The studies indicate that the use of heat pipe can reduce the temperature at high heat flux region of structure efficiently. However, there is a frozen startup period before the heat pipe reaching a steady operating state, and the sonic limit will be a restriction on the heat transfer capability. Thus, the effects of frozen startup must be considered for the design of HPC TPS. The simulation model and numerical method proposed in this paper can predict the heat transfer characteristics of HPC TPS quickly and exactly, and the results will provide important references for the design or performance evaluation of HPC TPS.