Numerical analysis of the radiation characteristics of a elliptical exhaust jet

The exhaust gas from a helicopter infra red suppressor is one of the significant infra-red radiation sources and a numerical analysis was conducted to investigate radiation characteristics for its design. A computational method for 3-D turbulent free flame jet exhausted from an elliptical jet pipe of helicopter was described. A k-Ε twin-equation turbulence model is used and a six-flux model is also used because it simulates radiative transfer by equations which are differential in form, and can be easily incorporated into existing computation schemes for solving the simultaneous differential equations representing the balance of mass, momentum, energy and chemical species. The SIMPLE algorithm and the formulation of the CTDMA are used to solve the finite-difference equations. The comparison of numerical results with experimental data shows that the numerical method presented here is generally feasible.