Session: 04-30 Emissions I

Paper Number: 153021

CFD Evaluation of Soot Formation in a Gas Turbine Combustor Using a Flamelet Progress Variable Approach 

An overview is provided of a CFD evaluation of soot formation in a RQL-type gas-turbine model combustor flowing ethylene and air at near-stoichiometric conditions. The National Combustion Code (OpenNCC) was used to perform reacting flow computations with a newly formulated Multiple Time-Scale (MTS) Flamelet Progress Variable (FPV) approach for DLR’s experimental combustor [1]. The MTS approach helped accelerate the convergence of soot quantities of interest by solving them as secondary progress variables, in addition to solving for the primary progress variable solution an FPV approach. Flow and flame characteristics, along with soot mass-fraction and soot-number density were predicted using a 75 species chemical kinetics model [2]. The CFD analysis predicted very similar flow characteristics and qualitatively similar soot mass fractions when compared with experimental data. The OpenNCC CFD analysis using the new MTSFPV approach and a two-equation soot-model [3] helped establish the framework to evaluate more detailed soot-modeling approaches in future computational studies.

1. Eberle, C., Gerlinger, P., & Aigner, M., ”A Comparison of URANS and LES For Soot Predictions in an Aero-Engine Model Combustor,” Deutscher Luft- und Raumfahrtkongress 2015, DocumentID: 370050.

2. Davis, S. G., Law, C. K., & Wang, H. (1999). Propene pyrolysis and oxidation kinetics in a flow reactor and laminar flames. Combustion and Flame, 119(4), 375-399. https://doi.org/10.1016/S0010-2180(99)00070-X

3. Fairweather, M., Jones, W. P., and Lindstedt, R. P., ”Predictions of Radiative Transfer from a Turbulent Reacting Jet in a Cross-Wind”, Combustion & Flame, Vol. 89, 1992, pp. 45-63.

Presenting Author: Kumud Ajmani HX5 LLC

Presenting Author Biography: Dr Ajmani has been associated with NASA Glenn Research Center in Cleveland, Ohio for over thirty years as a research engineer in the fields of aircraft engine and space propulsion design. His current interests include CFD development and analysis of gas turbine engine injectors and combustors for sustainable fuels and emissions reduction.

Authors:

Kumud Ajmani HX5 LLC
Francisco J. Guzman NASA Glenn Research Center
Kenji Miki NASA Glenn Research Center