FLOX®, or flameless combustion is characterized by ultralow $NOx$ emissions. Therefore the potential for its implementation in gas turbine combustors is investigated in recent research activities. The major concern of the present paper is the numerical simulation of flow and combustion in a FLOX®-combustor [Wünning, J. A., and Wünning, J. G., 1997, “Progress in Energy and Combustion Science,” 23, pp. 81–94; Patent EP 0463218] at high pressure operating conditions with emphasis on the pollutant formation. FLOX®-combustion is a highly turbulent and high-velocity combustion process, which is strongly dominated by turbulent mixing and chemical nonequilibrium effects. By this means the thermal nitric oxide formation is reduced to a minimum, because even in the nonpremixed case the maximum combustion temperature does not or rather slightly exceeds the adiabatic flame temperature of the global mixture due to almost perfectly mixed reactants prior to combustion. In a turbulent flow, the key aspects of a combustion model are twofold: (i) chemistry and (ii) turbulence/chemistry interaction. In the FLOX®-combustion we find that both physical mechanisms are of equal importance. Throughout our simulations we use the complex finite rate chemistry scheme GRI3.0 for methane and a simple partially stirred reactor (PaSR) model to account for the turbulence effect on the combustion. The computational results agree well with experimental data obtained in DLR test facilities. For a pressure level of 20 bar, a burner load of 417 kW and an air to fuel ratio of $λ$=2.16 computational results are presented and compared with experimental data.

1.
Wünning
,
J. A.
, Patent EP 0463218.
2.
Vaz
,
D. C.
,
Borges
,
A. R. J.
,
van Buijtenen
,
J. P.
, and
Spliethoff
,
H.
, 2004, “
On the Stability Range of a Cylindrical Combustor in the Flameless Oxidation Regime
,” GT2004–53790,
Proceedings of the ASME Turbo Expo 2004
, June 14–17,
Vienna, Austria
.
3.
Amsden
,
A. A.
,
O’Rourke
,
P. J.
, and
Butler
,
T. D.
, 1989, KIVA-II: A computer Program for Chemically Reactive Flows with Sprays. LA-11560-MS.
4.
Smith
,
G. P.
,
Golden
,
D. M.
,
Frenklach
,
M.
,
Moriarty
,
N. W.
,
Eiteneer
,
B.
,
Goldenberg
,
M.
,
Bowman
,
C. T.
,
Hanson
,
R. K.
,
Song
,
S.
,
Gardiner
,
W. C.
Jr.
,
Lissianski
,
V. V.
, and
Qin
,
Z.
, 1999, “
GRI3.0 mechanism version 3.07/30/99
,” see http://www.me.berkley.edu/gri_mechhttp://www.me.berkley.edu/gri_mech.
5.
Nordin
,
P. A. N.
, 1995, “
Complex Chemistry Modelling of Diesel Sprays
,” Ph.D. thesis, Chalmers University of Technology, Göteborg.
6.
Karlsson
,
J. A. J.
, 1995, “
Modelling Auto-Ignition, Flame Propagation and Combustion in Non-Stationary Turbulent Sprays
,” Ph.D. thesis, Chalmers University of Technology, Göteborg.
7.
Warnatz
,
J.
,
Maas
,
U.
, and
Dibble
,
R. W.
, 1997,
Verbrennung
,
Springer-Verlag
,
Berlin Heidelberg
, 2. Auflage.
8.
Lückerath
,
R.
,
Schütz
,
H.
,
Noll
,
B.
, and
Aigner
,
M.
, 2005, “
Experimental Investigations of FLOX®-Combustion at High Pressure
,” Flameless Combustion Workshop, Lund, Sweden, June 19–21.
9.
Meier
,
U. E.
,
Wolff-Gaßmann
,
D.
, and
Stricker
,
W.
, 2000, “
LIF Imaging and 2D Temperature Mapping in a Model Combustor at Elevated Pressure
,”
Aerosp. Sci. Technol.
1270-9638,
4
, pp.
403
414
.
10.
Leonard
,
G.
, and
Stegmaier
,
J.
, 1993, “
Development of an Aeroderivative Gas Turbine Dry Low Emission Combustion System
,” ASME Paper No. 93-GT-288.
11.
Byggstøyl
,
S.
, and
Magnussen
,
B. F.
, 1985, “
A Model for Flame Extinction in Turbulent Flow
,”
4th Symposium on Turbulent Shear Flows
, pp.
381
395
.
12.
Karlsson
,
J. A. J.
, and
Chomiak
,
J.
, 1995, “
Physical and Chemical Effects in Diesel Spray Ignition
,”
21st Congress of CIMAC
, Interlaken Switzerland, May 15–18.