Computation and Analysis of Dual Nozzle Flow Fields and Infrared Radiation

Abstract

Now adays, dual engines have been widely used on heavy aircraft , as shown in figure 1 . Distance between two engines is so short that gas exhausts from nozzles interact with each other, which affect the plume distribution and infrared radiation. The whole paper includes the following parts. Firstly, dual nozzle flow field is obtained via solving Reynolds averaged N -S equations. In the purpose of comput ing flow field, 'O' typed grids are used, and the grids between two nozzle are compressed, for that the distance between two nozzle is not so far enough . Consequently, it makes grids generation more complex . Finite volume method is used to solve the N -S equation, and the turbulent model is traditional B -L model. Computation region is extended and general boundary co ndition is like this, the inlet boundary condition s include both nozzle inner inlet and outer inlet , are giving total pressure, total temperature and Mach number . F ar-field is giving Mach number and static pressure . Outlet parameters are based on its Mach number. When the Mach number greater than 1, all the parameters are deduced from upstream , while the Mach number less than 1, all the parameters are deduced from upstream except for static pressure.