Numerical Simulation On Three Dimensional Heat Transfer And Flow Of Supercritical Hydrocarbon Fuel

Scramjet-powered air-breathing hypersonic vehicle has become a research focus nowadays. The regenerative cooling technology, which is one of the key technologies of thermal protection for scramjet engine, has become increasingly promient. So far, there is little research about three dimensional fluid dynamics and heat transfer for hydrocarbon fuel in regenerative cooling tube in our country, especially the research about the fuel decomposition and flow-rate distribution. Thus the research and systems analysis of regenerative cooling system is important for theoretical and engineering application.The article consists of six chapters. In the first one, the history and current status of the regenerative cooling technology at home and abroad are reviewed. The development of the numerical method based on the SIMPLE algorithm is introduced, the suitability of SIMPLE algorithm is validated for the simulation of fluid dynamics and heat transfer in the regenerative cooling tube. At last, the main content of the article is presented.The second chapter introduces the mathematical and physical models. First, based on the density variation with pressure and temperature at the supercritical state of the fuel, the incompressible SIMPLE algorighm is extended. A computational methods are development for the three-dimensional complicated laminar/turbulent flow, heat absorption and decomposition are developed. he generalized governing equations are deduced in curvilinear coordinates based on collocated grids with cancellation of pressure effect by momentum interpolation. Finally the parallel calculation algorighm is carried out and the corresponding software is written.In the third chapter, the software is validated through numerical simulation of the flows in a rectangular cavity, a 180-degree bended tube and a small curvature bended tube with square cross-section. Then the preliminary research is presented about the hydrocarbon fuel pyrolysis with heat absorption in the axisymmetric tube.The fourth chapter is the research for the heat transfer of cooling panel. First, The three-dimensional flow and heat transfer characteristics of refrigerant are explored in the scramjet regenerative cooling channels with focus on the convection and pyrolysis with heat absorption. Second, an experiment about the heat transfer of cooling panel for scramjet is finished, which may be the first one in china, and the results of numerical simulation shows good agreement with the experimental one. The results show that the pyrolysis of fuel can be achieved without catalyst when the temperature is above 870K. The fifth chapter is about the flow rate distribution in the sidewall of the scramjet engine. An experimental equipment is established with water as the cooling material. With experiment and numerical simulation, the influence of channel structure on the flow rate distribution of cooling material is researched, from which amount of data is collected that can be used for designing regenerative cooling structure of scramjet.The sixth chapter is conclusion. Most of the research and innovative points are reviewed and the outlook of future development is given.