Numerical Investigation Of Effusion-cooling Of Annular Flame Tube

The development of modern aero-engine requires combustion has high-temperature characteristics.Under the conditions of a fixed fuel/ air ratio,the burning gas consumption must be increased. Under condition of certain inlet flow of combustor,which means the cooling air consumption continuously decreases. Temperature-rise needs less cooling air,but wall cooling needs more cooling air ,this is contradictory. Therefore,a new and efficient cooling technology is urgently used in the flame tube .In this article,the effusion-cooling is used in the actual combustion chamber flame tube. In the actual working conditions, The article studies flame tube combustor with cooling film holes(model A) and four kind of inclined effusion cooling(model Bβ=0,H=0.2P; model C:β=0,H=0.4P;model Dβ=0,H=0.5P;model E:β=30o,H=0.5P).This article studies the effects of deflection angleβ=0 ,different Circumferential displacement H ,as well as Circumferential displacement H=0.5P, different deflection angleβon flow fields, Pressure fields, fuel spray fields, species fields, temperature fields and wall cooling effective.Numerical data are shown that:(1)The flame tube requires less cooling air, which is only about 23% of the total inlet flow rate of the combustor. It is 7% less than the cooling film holes.The wall temperature of flame tube with effusion cooling is between 900 and 1300K. Total pressure recovery coefficient is about 0.94 and OTDF is from 0.34 to 0.46.(2)Different circumferential displacement has an obvious effect on heat transfer charicteristics.The effusion-cooling combustor with circumferential displacement H=0.5P has well-proportioned flow fields and pressure fields, Total pressure recovery coefficient is relatively big. The OTDF of flame tube is small. The wall temperature distribution of flame tube shows a certain degree of regularity. The cooling air is about 22.9% of the total inlet flow rate of the combustor.The wall temperature of flame tube with effusion cooling is between 900 and 1160K.The effective is well than model B and C(3)Different deflection angle has an obvious effect on heat transfer charicteristics. The effusion-cooling combustor with deflection angleβ=30°has well-proportioned flow fields and pressure fields, The OTDF of flame tube is relatively small. The cooling air is about 22.9% of the total inlet flow rate of the combustor. The wall temperature of flame tube with effusion cooling is between 900 and 1120K. The effective is well than model D. Total pressure recovery coefficient is smaller than model D.The effusion-cooling of flame tube is a new compound and efficient cooling technology. To the development of high-performance aero-engine has great potential application value.