Numerical Study On Internal Flow Field Of Metallic Fuel Burner

With the progress of science and technology,the application of metal fuel engines in the Aerospace field is becoming more and more extensive in underwater navigation.As to metal fuel engine,no matter what kind of propulsion principle and fuel supply mode,as the core part of the whole power system,the combustion reaction organization inside the burner are very important.In order to improve the overall dynamic performance of Underwater weapon,it is crucial that to improve its internal combustion reaction.In this paper,for powdered supply of the combustion form of metal fuel mode,using FLUENT simulate the internal flow field of the metal fuel burner with different configuration calculation,consider the different physical structure factors: the second position of the nozzle spray droplets,the atomization of droplet,the different injection angle of spray droplets for the effect on the combustion efficiency of metal fuel.through research found:The same combustor configuration,the basic physical structure factors will not change the internal flow field of combustor pressure distribution,velocity distribution,the main influence of internal flow field of the combustion reaction,the temperature distribution,the aluminum metal particles and combustion products.the distance of the second position of the nozzle spray droplets and front burner is close,the position of high temperature and aluminum metal's reaction completely will be advanced,then promote aluminum particles and water more fully combustion reaction occurs.The atomization degree of droplet is higher,the location of the main reaction area will also be advanced,so as to make the reaction more complete.the different injection angle of spray droplets mainly affects the internal flow field at the front of the burner.the injection angle is 0 degrees,the product and heat of combustion in the combustor is gathered will have a certain impact on the structural material,the injection angle is 45 degree,make the temperature field distribution more uniform,the requirements for structural materials heat degree is low,which is conducive to improve the overall performance of the power system.The different configuration of burner will make very different internal flow field.Because of the existence of convergent section structure,the configuration of metal fuel burner that the ratio of the burner diameter is 1:0.8 or 1:0.6,where the first and second droplet nozzle position,can better increase the internal aluminum metal particle and water mixing effect,to further promote the reaction.In order to improve internal combustion efficiency,for the same configuration,considering a variety of factors,the distance of the second position of the nozzle spray droplets and front burner is close,the atomization degree is higher and the injection angle is 45 degree is the optimal design form;for the different burner configurations,it is the optimal design form that the configuration of metal fuel burner that the ratio of the burner diameter is 1:0.6,where the first and second droplet nozzle position.This study will provide a technical reference for improving the optimal design of the burners in Torpedo power system.