Influence of propagation direction on operation performance of rotating detonation combustor with turbine guide vane

Due to the pressure gain combustion characteristics,the rotating detonation combustor(RDC)can enhance thermodynamic cycle efficiency.Therefore,the performance of gas-turbine engine can be further improved with this combustion technology.In the present study,the RDC operation performance with a turbine guide vane(TGV)is experimentally investigated.Hydrogen and air are used as propellants while hydrogen and air mass flow rate are about 16.1 g/s and 500 g/s and the equivalence ratio is about 1.0.A pre-detonator is used to ignite the mixture.High-frequency dynamic pressure transducers and silicon pressure sensors are employed to measure pressure oscillations and static pressure in the combustion chamber.The experimental results show that the steady propagation of rotating detonation wave(RDW)is observed in the combustion chamber and the mean propagation velocity is above 1650 m/s,reaching over 84%of theoretical Chapman-Jouguet detonation velocity.Clockwise and counterclockwise propagation directions of RDW are obtained.For clockwise propagation direction,the static pressure is about 15%higher in the combustor compared with counterclockwise propagation direction,but the RDW dominant frequency is lower.When the oblique shock wave propagates across the TGV,the pressure oscillations reduces significantly.In addition,as the detonation products flow through the TGV,the static pressure drops up to 32%and 43%for clockwise and counterclockwise propagation process respectively.

Investigation on C_(2)H_(4)-Air combustion mode in a non-premixed rotating detonation combustor

Based on the working characteristics of the rotating detonation combustor,the combustion mode of C_(2)H_(4)-Air under non-premixed injection conditions is experimentally studied in this paper.By changing the equivalence ratio,we observed the acoustic deflagration mode,fast deflagration mode,stable detonation mode,and weak detonation mode in the combustor.The velocity and pressure of the shock wave increase gradually as the equivalence ratio increases from 0.6 to 1.8.The stable detonation region appears near the stoichiometric ratio and the velocity of the detonation wave is relatively stable.When the equivalence ratio of the mixture is larger than 1.32,the stable detonation wave will suddenly extinguish,forming a weak detonation mode until the end of the combustor operation.The combustion mode of weak detonation is greatly affected by the fuel injection pressure ratio,and the release rate of energy is the main reason for the formation of deflagration mode or detonation mode.