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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.

The heat transfer characteristics of aircraft icing process were investigated based on the theories of liquid–solid phase change and film flow. The heat transfer model which couples runback water flow with liquid–solid phase change was established and the influence of airflow parameters on the characteristics of icing growth was analyzed. The results indicate that the runback water on the icing surface will accelerate the liquid–solid phase change and the icing process. The shear stress caused by the airflow is the key factor to the runback water flow. The higher the airflow velocity, the greater the shear stress and stronger the runback water flow. Under the condition of runback water flow, the velocity and temperature of the airflow are the main causes effecting on the icing accretion. The higher the airflow velocity or the lower the temperature is, the greater the icing rate will be. The liquid water content (LWC) and the collection efficiency have weak effect on the icing rate comparatively.

Complex lifting entry was selected for precise landing performance during the Mars Science Laboratory entry. This study aims to develop the three-dimensional numerical method for precise computation and the surface panel method for rapid engineering prediction. Detailed flow field analysis for Mars exploration mission was performed by carrying on a series of fully three-dimensional Navier-Stokes computations. The static aerodynamic performance was then discussed, including the surface pressure, lift and drag coefficient, lift-to-drag ratio with the numerical and engineering method. Computation results shown that the shock layer is thin because of lower effective specific heat ratio, and that calculated results from both methods agree well with each other, and is consistent with the reference data. Aerodynamic performance analysis shows that CG location determines trim characteristics and pitch stability, and certain radially and axially shift of the CG location can alter the capsule lifting entry performance, which is of vital significance for the aerodynamic configuration design and inner instrument layout of the Mars entry capsule., {"references":["R.D. Braun, R.M. Manning, Mars exploration entry, descent, and landing\nchallenges, J. Spacecr. Rockets 44 (2) (2007) 310-323.","R. Prakash, P.D. Burkhart, A. Chen, K.A. Comeaux, C.S. Guernsey, D.M.\nKipp, D.W. Way, Mars Science Laboratory entry, descent, and landing\nsystem overview, in: Proceedings of Aerospace Conference, IEEE, 2008,\npp. 1-18.","K.T. Edquist, A.A. Dyakonov, M.J. Wright, C.Y. Tang,\nAerothermodynamic environments definition for the Mars Science\nLaboratory entry capsule, AIAA Pap. 1206 (2007) 8-11.","M.J. Wright, C.Y. Tang, K.T. Edquist, B.R. Hollis, P. Krasa, C.A.\nCampbell, A review of aerothermal modeling for Mars entry missions,\nAIAA Pap. 443 (2010) 4-7.","P.A. Gnoffo, K.J. Weilmuenster, R.D. Braun, C.I. Cruz, Effects of sonic\nline transition on aerothermodynamics of the Mars pathfinder probe, in:\nProceedings of AIAA, 1995, 1825-CP.","D.K. Prabhu, D.A. Saunders, On heatshield shapes for Mars entry\ncapsules, in: Proceedings of AIAA, 2002, 1221.","A. Viviani, G. Pezzella, Aerodynamic analysis of a capsule vehicle for a\nmanned exploration mission to Mars, in: Proceedings of the 16th\nAIAA/DLR/DGLR International Space Planes and Hypersonic Systems\nand Technologies Conference, AIAA, 2009, 7386.","P.A. Liever, S.D. Habchi, S.I. Burnell, J.S. Lingard, CFD prediction of\nthe Beagle 2 aerodynamic database, in: AIAA (2002) 0683.","E.H. Hirschel, C. Weiland, Selected aerothermodynamic design problems\nof hypersonic flight vehicles, Springer Press, New York, 2009.\n[10] J.D. Anderson, Jr., Hypersonic and high-temperature gas dynamics,\nAIAA, 2006.\n[11] G.J. Brauckmann, J.W. Paulson Jr., K.J. Weilmuenster, Experimental and\ncomputational analysis of shuttle orbiter hypersonic trim anomaly, J.\nSpacecr. Rockets 32 (5) (1995) 758–764.\n[12] K.J. Weilmuenster, H.H. Hamilton, A comparison of computed space\nshuttle orbiter surface pressures with flight measurements, AIAA, 1982,\n0937.\n[13] R.A. Mitcheltree, P.A. Gnoffo, Wake flow about the Mars pathfinder\nentry vehicle, J. Spacecr. Rockets 32.5 (1995) 771-776.\n[14] K.T. Edquist, P.N. Desai, M. Schoenenberger, Aerodynamics for the\nMars Phoenix entry capsule, in: Proceedings of AIAA/AAS\nAstrodynamics Specialist Conference and Exhibit, AIAA, 2008, 7219.\n[15] R.C. Weast, CRC Handbook of Chemistry and Physics, 65th ed.\nChemical Rubber Company Press, Cleveland, 1984.\n[16] A Fenghour, W.A. Wakeham, V. Vesovic, The viscosity of carbon\ndioxide, J. Phys. Chem. Ref. Data 27 (1) (1998) 31–44.\n[17] M.S. Holden, T.P. Wadhams, G.J. Smolinski, M.G. MacLean, J. Harvey,\nB.J. Walker, Experimental and numerical studies on hypersonic vehicle\nperformance in the LENS shock and expansion tunnels, AIAA Pap. 125\n(2006) 2006.\n[18] M. MacLean, M.S. Holden, Catalytic effects on heat transfer\nmeasurements for aerothermal studies with CO2, AIAA Pap. 182 (2006)\n9-12.\n[19] X. Yang, W. Tang, Y. Gui, Y. Du, G. Xiao, L. Liu,Hypersonic static\naerodynamics for Mars science laboratory entry capsule, Acta Astronaut.\n103 (2014) 168-175."]}

Investigation on the heat transfer mechanisms of liquid and solid is important to predicting the icing process. Messige model is a typical model for the process of mass and heat transfer, but the effect of surface tension of water droplet is been ignored in the model. We established a model which was add the infection of surface energy based on traditional thermodynamic model. Some cases at NACA0012are simulated with our model in order to verify its correctness. The calculated results show that, ourmodel was consistent with the traditional thermodynamic model in Low temperature, but our model havebetterresults in high temperatures