Denis Roger Henri Ansart

Ramjet NOx Emission: Use of a 3D CFD Method for the Combustor Design of a Super/Hyper-Sonic Transport Propulsion System

As part of SNECMA participation in developing the ramjet of Large-scale Japanese Project for “SUPER/HYPER-SONIC TRANSPORT PROPULSION SYSTEM”, an injection system of lean premix type has been studied.This concept based on a low fuel/air ratio combustion allows a high reduction of NOx emission. Fuel and air mixing must be rapid and homogeneous in order to obtain the full potential of this principle.For that purpose, a numerical study has been carried out to find the optimal mechanism on carburation homogeneity. Results of a parametric study are presented and show influences of various injection and flame holder systems on air/fuel flow distributions.Numerical simulations have been performed with the 3D CFD ECRIN code. It is commonly used at SNECMA for combustion analysis. The main features of this code are presented and more particularly the combustion and NOx emission modeling. A comparison of calculated NOx emission indexes with experimental results obtained in a tubular combustor conducts to a good agreement between experiments and computations.Copyright