Document Type : Original Article


1 Space Transportation Research Institute, Iranian Space Research Center

2 Department of Aerospace Engineering, Sharif University of Technology, Tehran, Iran


The aim of this study is to evaluate the performance of water-jacket cooling system for thermal protection of exhaust large dimension diffuser at high heat fluxes in a wide range of coolant pressure. For this purpose, using the developed calculation code, the parameters of the water-jacket cooling system are determined so that in addition to satisfying the temperature conditions of the metal body, the total pressure drop has remained in the desired range. In the following, the capability of numerical code to design and performance analysis of the cooling system has been evaluated in coolant pressure of 3 to 50 bar and high heat fluxes up to 3.5 MW/m2. The present studies show that the proper selection of coolant pressure is very important in the design of the cooling system with optimal mass flow rate and minimum coolant dimensions, especially at high heat fluxes, so that increasing the coolant pressure from 3 to 10 bar, in addition to significantly reducing the dimensions of the cooling system, reduces the mass flow rate by 75%.


Main Subjects

## N. Fouladi, A. Mohammadi, and H. Rezaei, “Numerical Investigation of Pre-evacuation Influences of Second Throat Exhaust Diffuser,” Journal of Fluid Mechanics and Aerodynamics, vol. 2, pp. 55–69, 2017.##
## N. Fouladi, “Numerical investigation of back flow arrester effect on altitude test simulator starting performance,” Journal of Modares Mechanical Engineering, vol. 17, no. 7, 2017.##
## R. M. Kumaran, T. Sundararajan, and D. R. Manohar, “Performance Evaluation of Second-Throat Diffuser for High-Altitude-Test Facility,” Journal of Propulsion and Power, vol. 26, no. 2, pp. 248–258, 2010.##
##B. H. Park, J. Lim, S. Park, J. H. Lee, and W. Yoon, “Design and Analysis of a Second-Throat Exhaust Diffuser for Altitude Simulation,” Journal of Propulsion and Power, vol. 28, no. 5, pp. 1091–1104, 2012.##
##N. Fouladi,  S. A. Mirbabaei, and M. Khosroanjom, “Experimental Study of the supersonic exhaust diffuser spray cooling system,” Amirkabir Journal of Mechanical Engineering, vol. 52, no. 7, pp. 61–70, 2019.##
## S. Park, B. H. Park, J. Lim, and W. Yoon, “Improvement of Starting Performance in Supersonic Exhaust Diffuser with Second Throat for High Altitude Simulation,” In Proceedings of the Korean Society of Propulsion Engineers Conference, pp. 321-327, 2008.##
## K. Yim, H. Kim, and S. Kim, “A Numerical Study on Flow and Heat Transfer Characteristics of Supersonic Second Throat Exhaust Diffuser for High Altitude Simulation,” Journal of the Korean Society of Propulsion Engineers, vol. 18, no. 5, pp. 70–78, 2014.##
##M. Mahdian, “Design and analysis of an optimal cooling system for a supersonic exhaust diffuser using a water jacket,” Master’s Thesis, Dept. Aerospace Eng., Sharif Univ. of Tech., Tehran, Iran, 2021.##
## S. Jo, S. Han, H. J. Kim, and K. J. Yim, “Numerical study on the flow and heat transfer characteristics of a second throat exhaust diffuser according to variations in operating pressure and geometric shape,” Journal of Energies, vol. 14, no. 3, 2021.##
##      K. Annamalai, K. Visvanathan, V. Sriramulu, and K. A. Bhaskaran, “Evaluation of the performance of supersonic exhaust diffuser using scaled down models,” Journal of  Experimental Thermal and Fluid Science, vol. 17, no. 3, pp. 217–229, 1998.##
##    M. Farahani, N. Fouladi, and A. Mirbabaei, “Design and analysis of a cooling system for a supersonic exhaust diffuser,” Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering, vol. 233, no. 14, pp. 5253–5263, Nov. 2019.##
##  M. E. Boysan, “Analysis Of Regenerative Cooling In Liquid Propellant Rocket Engines,” Master of Science , Dept. Mechanical Eng., Middle East Technical University, Ankara, Turkey, 2008.##
##E. Atefi and M. H. Naraghi, “Optimization of Regeneratively Cooled Rocket Engines Cooling Channel Dimensions,” Conference of AIAA Propulsion and Energy 2019 Forum, p. 3938, Indianapolis, Indiana, USA, 2019.##
## M. Naraghi, S. Dunn, and D. Coats, “A Model for Design and Analysis of Regeneratively Cooled Rocket Engines,” in 40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, p. 3852, Fort Lauderdale, Florida, USA, 2004.##
##M. Q. Brewster, “Radiation-stagnation flow model aluminized solid rocket motor internal insulator heat transfer,” Journal of Thermophysics and Heat Transfer, vol. 3, no. 2, pp. 132–139, 1989.##
## K.-Z. Li, X.-T. Shen, H.-J. Li, S.-Y. Zhang, T. Feng, and L.-L. Zhang, “Ablation of the carbon/carbon composite nozzle-throats in a small solid rocket motor,” Journal of Carbon, vol. 49, no. 4, pp. 1208–1215, 2011.##
## X. Chen, R. Liu, and H. Y. Du, “Erosion Study of Silica Phenolic Nozzles with Graphite Inserts in Solid Rocket Motors,” Advanced Materials Research conference, vol. 1095, pp. 573–578, Trans Tech Publication, Switzerland 2015.##
##  E. ToolBox, (2005), “Water Boiling Points at Higher Pressure,” [On-line], Available:, Visited in Feburary 5th, 2022.##
## J. Dirker and J. P. Meyer, “Convection Heat Transfer In Concentric Annuli,” Journal of Experimental Heat Transfer, vol. 17, no. 1, pp. 19–29, 2004.##
##N. Fouladi, M. Farahani, and M. Mahdian, “Design and analysis of a metal diffuser cooling system by water jacket method,” in 19th Fluid Dynamics Conference, Sharif University of Technology, Tehran, Iran, 2021.##
## T. L. Bergman, F. P. Incropera, D. P. DeWitt, and A. S. Lavine, Fundamentals of heat and mass transfer, 6th ed. New York: John Wiley & Sons, 2006, pp.486-533.##