Influence of the geometry of the nozzle on the characteristics of an exhaust jet

Two solutions for the parameters of a turbulent exhaust jet of a dual-duct engine - the traditional solution within the framework of Prandtl equations of the type of boundary-layer equations and calculation of the near-range field within the framework of the Navier-Stokes equations with subsequent calculation within the framework of the Prandtl equations for large distances - have been compared. It has been shown that the influence of the real geometry of the nozzle exit section, including the shift of the center body and the main duct forward from the exit section of the cold secondary duct, can be allowed for by correcting the constant of the source term in the differential equation for turbulent kinematic viscosity. © Springer Science+Business Media, Inc. 2006.