Numerical Study On Performance And Wall Heat Transfer Of Rotating Detonation Engine Combustion Chamber

With the continuous improvement of aero-engine technology,it has been found that detonation combustion has the advantages of rapid heat release and high thermal cycle efficiency.The rotating detonation engine(RDE)can achieve a continuous rotation of a single ignition to produce a stable thrust.In order to understand the performance of RDE combustion chamber and explore the method of wall cooling,this paper mainly studies the effects of mixed gas equivalent ratio,total injection pressure,outlet back pressure and axial length of combustion chamber on the rotating detonation engine combustion chamber.Give the method to study the method for unsteady wall change the heat and use the 2D numerical prediction distribution of RDE combustion chamber wall temperature.Finally,the impact cooling characteristics under the large heat flux are studied and analysis the influence of the RDE combustion chamber wall cooling.In this paper,the performance of RDE combustion chamber is studied.In the range of the parameters studied in this paper,the study shows that: When the inlet equivalent ratio φ is increases from 0.3 to 1.5,the combustion chamber pressure ratio is first increase and then decrease,when the equivalence ratio is 1,the maximum value is reached,but the combustion efficiency decreased gradually with the increase of equivalence ratio,and the combustion efficiency decreases slightly when the equivalence ratio is less than 1,and the combustion efficiency decreases rapidly when the equivalence ratio is greater than 1;The combustion efficiency increases with the increase of the total injection pressure and the back pressure ratio;When the combustion chamber axial length X is increases from 0.05 m to 0.1m,the combustion chamber pressure ratio decreases,and the combustion efficiency increases.In this paper,a method for studying the unsteady wall temperature of RDE at high frequency is presented,and using 2D numerical calculation method to predict the RDE wall temperature of combustion chamber.It is found that when there is not the cooling structure,within a short time after ignition,the wall temperature reached more than 1000 K,And the temperature distribution along the axial direction is uneven.Finally,the distribution of heat flux and temperature in the combustion chamber of a rotating detonation engine is analyzed.The 3D numerical calculation of the cooling characteristics of the impingement cooling wall of RDE combustor is carried out.The results show that the impact cooling effect is better when the impact hole diameter is d = 4mm,the impact spacing is H = 4mm,and the hole spacing is Xn = Yn = 35.168 mm under the same boundary condition.Stdudies have shown that when the jet Reynolds number reached 50000,and the wall temperature can reduce to a reasonable range at high heat flux.