Thermodynamic Analysis And Numerical Simulation Of Metal Powdered Fuel Afterburner

With the continuous development of aviation technology,high-altitude aircraft will play an increasingly important role,and was put forward a higher performance requirements?long life,supersonic flight,anti-jamming,etc.?.Ordinary fuel-based aero engines make it difficult for the aircraft to meet this high performance requirement.When the aircraft is flying at high altitude,the oxygen content of the air is greatly reduced compared to the ground,and the oxygen content in the afterburner will be further reduced.Under the conditions of poor oxygen,is not conducive to aviation kerosene fire and complete combustion,affecting the flight performance of the aircraft.It has become the main obstacle to the aircraft at high altitude for a long time to maintain high-speed flight.This paper will initially explore and study a kind of magnesium powder based afterburner system,and its feasibility also be analyzed and discussed.Firstly,the combustion reaction of magnesium powder in aerosol engine exhaust and nitrogen was calculated by CEA?Chemical Equilibrium and Application?software.Magnesium powder particles in the aeroengine exhaust combustion,the first reaction with the exhaust O₂ and CO₂,and then react with N₂;magnesium particles in the nitrogen when ignited,and nitrogen reaction will produce Mg₃N₂ and MgN.However,in both cases,the amount of magnesium powder particles reacted with nitrogen is particularly small.Secondly,the theoretical analysis of the aerodynamic process of the aeroengine is carried out in two cases without additional afterburner and metal powder afterburner.The results show that the metal powder afterburner system can provide positive thrust for the system.Finally,based on a small turbojet engine model,on the basis of its original device for the design of a cavity afterburner combustion chamber structure.The internal flow field of three different aspect ratio cavities is simulated and analyzed.The basic idea and hypothesis of combustion model of magnesium powder particles are established.The combustion model of magnesium powder and nitrogen reaction is assumed.The reaction of magnesium powder with nitrogen was numerically simulated.The simulation results show that the cavity combustion chamber can be used as a special combustion chamber structure to form a vortex structure in the cavity to promote the effective combustion of the fuel.The combustion of the magnesium powder particles shows that the magnesium powder can react with nitrogen to produce a lot of heat.