Investigations On The Field Structure And Performance Of The Rotating Detonation Combustion Chamber

Rotating detonation combustor will be widely applied because of its such prominent features as simple construction,stably burning,small volume and high energy efficiency.As a new kind of combustor,the researches on the rotating detonation combustor are still in a primary stage;the combustor geometry,structure and boundary conditions are significant factors that affect its good performances.Therefore,the analysis of the flow-field structure and the influential factors of Rotating detonation combustor are significant to the further researches on Rotating Detonation Combustor.In order to analyze flow field structure and effects of different factors on RDC performance,this paper is to use two-dimension numerical simulation on ring section and unfolded surface of rotating detonation combustor respectly,to solve two-dimensional unsteady Euler equations on the basis of display format,and to analyze respective propagation processes of detonation wave in the annular flow field and rectangular flow field with the ignorance of viscous,heat conduction and diffusion.The main contents are as follows.1.This thesis makes two-dimension numerical simulation on ring section to analyze the annular flow field when detonation wave propagates stably.The results show that,in the annular flow field of detonation,the detonation products have tendency to move to the external wall due to the effects of the high temperature expansion and the internal and external wall convergence divergence after the detonation wave,which forms flow field characteristics that fuel can be conducively filled.2.This thesis makes studies on how geometry parameters affect the features of the detonation wave propagation and its flow field structure in the annular flow field.The results show that,in the scope of this thesis calculated,when the ratio of the width and diameter is no greater than 1/6,the pressure of the detonation products area is relatively low,which is more conducive for the premixed gas injection;3.It is to study the flow field structure and its performances at the expanded circumferential surface of combustor and explore the influence of boundary conditions on the characteristics of RDC.The results show that the supercharge ratio of the detonation combustor can reach 2.88.The propagation speed of the detonation wave will arise when the injection pressure increases,the pressure ratio will first increase and then decrease;The propagation speed of the detonation wave and the pressure ratio of the combustion chamber will arise when the flow temperature decreases at the entrance of the combustor;The combustor's back pressure have great impact on initiating process.4.The propagation process of the detonation wave is studied in the obstacle of a wedge structure laid by the combustor inlet side,and the flow field structure of RDC and its performances are analyzed by initiating one or two strands of detonation wave both in the obstacle-free detonation combustor and wedge detonation combustor.The results show that wedge combustor contributes to the production of the detonation wave propagating in one direction;Using the appropriate slope of the combustor entrance will help to increase the propagation speed of the detonation wave and the pressure ratio of the combustion chamber.Initiating double detonation wave in a lager-sized combustor can improve the stability of its work performance but may lower down its ability to work.