The Pulse Detonation Engine Inlet Flow Field And Knocking Numerical Study

As a new concept propulsion system, pulse detonation engines show many advantages over their conventional counterparts. During the last decades, the research of pulse detonation engines surged over the world and the application and principle research regarding pulse detonation engines reached a prehistoric peak. Based on the open source code -DUNS for CFD, numerical investigation has been carried out in the thesis to gain an insight into the flow field of a supersonic inlet for pulse detonation engines and the phenomenon of gas mixture detonation.The thesis firstly makes a brief introduction for the open source code-DUNS and reviews the current research of inlets for pulse detonation engines and gas mixture detonation in chapter 1, and then provides a detailed and systematic description of algorithms embedded in the open source code-DUNS in chapter 2, solves a series of problems frequently occurring during the applications of DUNS in flow field simulation and extends some auxiliary functions of DUNS in appendix 2.Based on the above, DUNS is exploited in this thesis to deal with some practical flow field simulations regarding pulse detonation engines.Firstly, a numerical investigation of the internal flow field inside an axisymmetric supersonic inlet for an air-breathing pulse detonation engine has been performed and a detailed analysis of the influences of perturbation pressure with different amplitudes or frequencies and other different boundary conditions imposed at the exit of the supersonic inlet on the motion of terminal shock inside the supersonic inlet have been provided in chapter 3.Secondly, in chapter 4, detailed chemistry and parallel computation have been utilized to run the simulation of gas mixture(30%(2H2+O2)+70%AR in moles) detonation under the initial condition with pressure 6670Pa and temperature 298K. Unique, detailed and regular flow structures in the flow field of detonation have been obtained. The analysis for the formation, characteristic and the interaction between triple points has been provided. And the transitions of strong detonation to self-sustained detonation and deflagration to self-sustained detonation are also illustrated. The results and conclusions obtained show a strong coherence with those by others.At last, chapter 5 summarizes the research work and draws conclusions and points out the recommendation for further research.