Research On Numerical Simulation Of Heat Flow On Three-dimension Longitudinal Heat Shield

In arbitrary curvilinear coordinate systems,three dimensional turbulent combustion flow fields of the three kinds of turbofan engine afterburner with the longitudinal heat shield,outer cold flow and the jet nozzle are simulated. The three-dimensional body-fitted grids are generated by an elliptical grid generation procedure and zone method. The k-εmodel is employed to describe the turbulent characteristics. EBU-Arrehenius and Second-moment turbulent combustion model are used to determine the reaction rate. To consider the influence of heat radiation on the gas temperature and wall temperature, the six flux model is applied to predictions of heat flux distributions. The discretization of governing equations on a non-staggered grid system is performed by hybrid scheme over the control volume, and discretization equations are solved with SIMPLE algorithm. In arbitrary curvilinear coordinates,the wall function is used for treating near wall regions. The influences of two different inlet gas parameter distributions and turbulent combustion models, as well as three different afterburners on turbulent combustion flow fields and wall temperature profiles are calculated. Comparisons of experiment results and calculations results show that Second-moment combustion model is reasonable for modeling turbulent reacting flows, inlet gas parameter distributions is more important .Calculation method is reliable and can be used for the optimum design of afterburner.