Research On Superfine Atomization And Detonation Airflow Distribution Structure

After nearly 100 years of development,the technology of gas turbine and turbofan engine based on isobaric combustion technology has been very mature and perfect.It has become very difficult to greatly improve the propulsion efficiency of these machines.Detonation combustion overcomes the inherent defects of the existing isobaric combustion resulting in the decrease of working capacity of the working fluid,and improves the work capacity of its working substance in the process of combustion and heating.Therefore,the detonation engine has gained great attention from various advanced ways.The detonation propulsion device is organized by detonation,and the combustion process is approximately equal to the constant volume combustion.Detonation wave is a combustion form that is coupled by shock wave and combustion wave and propagate at supersonic speed.The energy release rate is fast,and its product has higher pressure and temperature.The efficiency of thermal cycle is high,which is nearly 20% higher than that of conventional isobaric combustion.Based on detonation combustion technology,the study of rotary detonation combustion is carried out.Diesel is used as fuel,and then the superfine atomization,cold mixing and detonation flow characteristics of diesel are analyzed sequentially.1.Ater the model validation,using KH-RT model to simulate the Laval nozzle,superfine atomization in Laval throat injection can meet the basic diesel(SMD ? 10?m),also found that the increase of Laval nozzle size can enhance the atomization characteristics,but the empty gas atomization was required to increase,also easy to cause tempering.The fuel is sprayed into the vertical atomization of Laval nozzle in the best appropriate small angle can increase the fuel evaporation.2.Analyze the different jet design of a rotating detonation engine through the axisymmetric non reaction calculation method.The stoichiometric ratio of C10H22 and air is passed into the RDE of the two-dimensional simplified model,numerical simulation with the air inlet groove structure best mixing effect prediction of ignition position is more than 60 mm,with an air inlet groove structure has better mixing effect,predict the ignition position more than 20 mm.3.we have detonated the mixed flow field and detonated successfully within or near the mixing boundary.The continuous detonation wave structure is obtained.The pressure of the detonation wave surface reaches 2MPa,and the temperature reaches 3000 K.4.Analyze the detonation characteristics of C10H22-Air with the different inflow total pressure,the total inlet temperature,the axial size and the circumferential dimension by the numerical simulation.The inflow pressure has a great influence on mass flow,peak pressure and outlet pressure,and the mass flow rate increases by nearly 30% per 1atm.The increase of flow temperature will reduce the turbocharging characteristics of the detonation chamber.The temperature increases by about 50 K,and the turbocharging characteristics are reduced by about 5%.The height of the detonation wave is influenced by the circumferential dimension,and the axial size depends on the height of the detonation wave.