4e0bc426-9a3e-4480-b692-709a10c892f920230109080006437wseas:wseasmdt@crossref.orgMDT DepositWSEAS TRANSACTIONS ON ENVIRONMENT AND DEVELOPMENT2224-34961790-507910.37394/232015http://wseas.org/wseas/cms.action?id=40311420221420221810.37394/232015.2022.18https://wseas.com/journals/ead/2022.phpMustafa B.Al-HadithiChemical and Petrochemical Engineering Department, College of Engineering, University of Anbar, Anbar, IRAQAbdulhassan A.KaramallaMechanical Engineering Department, University of Technology, Baghdad, IRAQThis paper describes the developed method for predictions of transient internal surface temperatures and heat-flux obtained from thermocouples, which are installed through the wall of the rocket motor nozzle. Heat-Flux was estimated by using the prediction of internal surface temperatures from numerical solutions of the inverse heat conduction problem (IHCP). Three Heat-Flux gauges are manufactured and used in convergent, throat, and divergent sections. The temperatures are measured with starting operation of the rocket motor along the gauges where the thermocouples are connected to the data acquisition system interfacing with the PC. The measured unsteady temperature behavior is approximated by polynomials third degree in space and time. The measurement results indicate that the maximum reading temperatures are at the throat section. No differences in time were appearing in curves to reach maximum prediction surface temperatures.123120221231202213041311123https://wseas.com/journals/ead/2022/c545115-950.pdf10.37394/232015.2022.18.123https://wseas.com/journals/ead/2022/c545115-950.pdfLiebert C.H., "An Investigation of the Compatibility of Radiation and Convection Heat Flux Measurements", NASA – TM – 107205, 1996. 10.1155/2018/8783946W. Shoubin, Z. Li, S. Xiaogang, and J. Huangchao, "Inversion of thermal conductivity in two-dimensional unsteadystate heat transfer system based on boundary element method and decentralized fuzzy inference", Complexity, vol. 2018, Article ID 8783946, pp.1-9, 2018. 10.1155/2018/6741632S. Wang, Y. Deng and X. Sun, "Solving of two-dimensional unsteady inverse heat conduction problems based on boundary element method and sequential function specification method", Complexity, vol. 2018, Article ID 6741632, 2018, 11 pages. 10.1155/2018/3723949S.Wang, H. Jia, X. Sun, and L. Zhang, "Research on the recognition algorithm concerning geometric boundary regarding heat conduction based on BEM and CG", Mathematical Problems in Engineering, vol. 2018, Article ID 3723949, pp. 1-13, 2018. 10.1155/2017/2861342S. Wang, L. Zhang, X. Sun et al., "Solution to two-dimensional steady inverse heat transfer problems with interior heat source based on the conjugate gradient method", Mathematical Problems in Engineering, vol. 2017, Article ID 2861342, pp. 1-9, 2017. 10.1155/2017/2461498S. Wang, H. Jia, X. Sun et al., "Twodimensional steady state boundary shape inversion of CGM-SPSO algorithm on temperature information", Advances in Materials Science and Engineering, vol. 2017, Article ID 2461498, pp.1-12,2017. 10.1016/j.ijheatmasstransfer.2007.05.004C. Fieberg, R. Kneer, "Determination of thermal contact resistance from transient temperature measurements", International Journal of Heat and Mass Transfer, Vol.51, pp 1017–1023, 2008. 10.1515/ijnsns.2008.9.3.275M. S. Dargusch1, A. Hamasaiid1 et al., "An Inverse Model to Determine the Heat Transfer Coefficient and its Evolution with Time during Solidification of Light Alloys", International Journal of Nonlinear Sciences and Numerical Simulation, Vol.9, No.3, pp 275-282, 2008. 10.1016/j.expthermflusci.2017.01.021Hua Liu, Xinlin Xia et al., "Experimental investigations on temperature-dependent effective thermal conductivity of nanoporous silica aerogel composite", Experimental Thermal and Fluid Science, Vol.84, pp 67-77, 2017. 10.1155/2019/7432138Shoubin Wang and Rui Ni, "Solving of TwoDimensional Unsteady-State Heat-Transfer Inverse Problem Using Finite Difference Method and Model Prediction Control Method", Hindawi Complexity, Vol. 2019,Article ID 7432138, pp.1-12, 2019. 10.2514/3.7846Mehta R.C., "Estimation of Heat – Transfer Coefficient in a Rocket Nozzle", AIAA Journal, Vol.19, No.8, 1981, pp 1085-1086,. Anderson D.A., "Computational Fluid Dynamics", McGraw-Hill Inc., 1995. Nogier J.P , "Methodes de Calcul Numerique", ISBN 2-225-78980-0, Masson, Paris, 1983. Bolton W. , "Measurement and Instrumentation System", ISBN 0 7506 3114 7, British Library, London, 1996. "Manual on the Use of Thermocouples in Temperatures Measurements", ASTM Publications, 1971. Marvian D.S. and Isoidore W., “Experimental Determination of Time Constant and Nusselt Numbers for Bare-Wire Thermocouples in High-Velocity air Streams and Analytic Approximation of Conduction and Radiation Errors”, NASA- TN 2599, Washington, January, 1952. 10.2514/3.60607Sternfelf H. J. and Reinkenhof J., "Technique for Determining Local Heat – Transfer Coefficients”, AIAA Journal, Vol.15, No.1, 1977, pp 105-109.