Fuel-air mixing in a direct injection spark ignition (DISI) engine occurs in a highly unsteady, turbulent and three-dimensional flow. As a result, any cycle-to-cycle unsteady variation in the mixing process can directly impact the performance of the DISI engine. To study the unsteady process in these engines, we have developed and implemented a large-eddy simulation (LES) approach with an innovative subgrid scalar mixing model based on the linear-eddy mixing (LEM) model into a commercial IC engine code (KIVA-3V). Time-averaged results of the simulations using the new LES version (KIVALES) are compared to the steady-state predictions of the original KIVA-3V. Significantly different in-cylinder turbulent fuel-air mixing is predicted by these two methods. Analysis shows that KIVALES resolves spatial features larger than the grid and that the subgrid kinetic energy adjusts to the LES resolution. As a result, KIVALES captures a highly unsteady, anisotropic fuel-air mixing process whereas a more diffused mixed field is predicted by the original KIVA-3V. This ability of KIVALES is attributed to the subgrid closure which scales the subgrid dissipation with the local grid size and thus, decreases the overall dissipation in the flow.

Issue Section:
Injection and Fuel Air Mixture Preparation
Keywords:
internal combustion engines, flow simulation, numerical analysis, engineering computing, mixing, fuel, turbulence, convection
Topics:
Cylinders, Eddies (Fluid dynamics), Energy dissipation, Engines, Flow (Dynamics), Fuels, Internal combustion engines, Kinetic energy, Large eddy simulation, Resolution (Optics), Scalars, Simulation, Turbulence, Cycles, Direct injection spark ignition engines, Modeling
1.
Anderson, R. W., Yang, J., Brehob, D. D., Vallance, J. K., and Whiteaker, R. M., 1996, “Understanding the Thermodynamics of Direct Injection Spark Ignition (DISI) Combustion Systems: An Analytical and Experimental Investigation,” SAE Paper No. 962018.
2.
Iwamoto, Y., Noma, K., Nakayama, O., Yamauchi, T., and Ando, H., 1997, “Development of Gasoline Direct Injection Engine,” SAE Paper No. 970541.
3.
Galperin, B., and Orszag, S., eds., 1993, Large Eddy Simulation of Complex Engineering and Geophysical Flows, Cambridge University Press, New York.
4.
Menon
,
S.
,
2000
, “
Subgrid Combustion Modelling for Large-Eddy Simulations
,”
Int. J. Engine Res.
,
1
(
2
), pp.
209
–
227
.
5.
Smagorinsky
,
J.
,
1963
, “
General Circulation Experiments With the Primitive Equations: I. The Basic Equations
,”
Mon. Weather Rev.
,
91
, pp.
99
–
164
.
6.
Mungal
,
M. G.
, and
Dimotakis
,
P. E.
,
1984
, “
Mixing and Combustion With Low Heat Release in a Turbulent Shear Layer
,”
J. Fluid Mech.
,
148
, pp.
349
–
382
.
7.
Menon, S., McMurtry, P. A., and Kerstein, A. R., 1993, “A Linear Eddy Mixing Model for Large Eddy Simulation of Turbulent Combustion,” Large Eddy Simulation of Complex Engineering and Geophysical Flows, B. Galperin and S. Orszag, eds., Cambridge University Press, New York, pp. 287–314.
8.
Han
,
Z.
, and
Reitz
,
R. D.
,
1995
, “
Turbulence Modeling of Internal Combustion Engines Using RNG k-ε Models
,”
Combust. Sci. Technol.
,
106
, pp.
267
–
295
.
9.
Celik
,
I.
,
Yavuz
,
I.
,
Smirnov
,
A.
,
Smith
,
J.
,
Amin
,
E.
, and
Gel
,
A.
,
2000
, “
Prediction of In-Cylinder Turbulence for IC Engines
,”
Combust. Sci. Technol.
,
153
, pp.
339
–
368
.
10.
Menon
,
S.
,
Yeung
,
P.-K.
, and
Kim
,
W.-W.
,
1996
, “
Effect of Subgrid Models on the Computed Interscale Energy Transfer in Isotropic Turbulence
,”
Comput. Fluids
,
25
(
2
), pp.
165
–
180
.
11.
Kim
,
W.-W.
,
Menon
,
S.
, and
Mongia
,
H. C.
,
1999
, “
Numerical Simulations of Reacting Flows in a Gas Turbine Combustor
,”
Combust. Sci. Technol.
,
143
, pp.
25
–
62
.
12.
Kim
,
W.-W.
, and
Menon
,
S.
,
1999
, “
A New Incompressible Solver for Large-Eddy Simulations
,”
Int. J. Numer. Methods Fluids
,
31
, pp.
983
–
1017
.
13.
Chakravarthy
,
V. K.
, and
Menon
,
S.
,
2000
, “
Modeling of Turbulent Premixed Flames in the Flamelet Regime
,”
Combust. Sci. Technol.
,
162
, pp.
1
–
50
.
14.
Chakravarthy
,
V. K.
, and
Menon
,
S.
,
2000
, “
Subgrid Modeling of Premixed Flames in the Flamelet Regime
,”
Flow, Turbul. Combust.
,
65
, pp.
131
–
161
.
15.
Amsden, A. A., O’Rourke, P. J., and Butler, T. D., 1989, “KIVA-II: A Computer Program for Chemically Reactive Flows With Sprays,” Technical Report LA-11560-MS, Los Alamos National Laboratory, May.
16.
Pannala, S., and Menon, S., 2000, “On Large Eddy Simulations of Reacting Two-Phase Flows,” Technical Report CCL-00-006, Georgia Institute of Technology, Atlanta, GA, May.
17.
Menon
,
S.
, and
Calhoon
,
W.
, 1996, “Subgrid Mixing and Molecular Transport Modeling for Large-Eddy Simulations of Turbulent Reacting Flows,” Proc. Combust. Inst., 26, pp. 59–66.
18.
Kerstein
,
A. R.
,
1991
, “
Linear-Eddy Modelling of Turbulent Transport. Part 6. Microstructure of Diffusive Scalar Mixing Fields
,”
J. Fluid Mech.
,
231
, pp.
361
–
394
.
19.
Chakravarthy
,
V. K.
, and
Menon
,
S.
,
2000
, “
Linear-Eddy Simulations of Schmidt and Reynolds Number Scaling of Scalar Mixing
,”
Phys. Fluids
,
13
, pp.
488
–
499
.
20.
Sone, K., Patel, N. V., and Menon, S., 2001, “KIVALES—Large-Eddy Simulations of Internal Combustion Engines. Part I: Theory and Formulation,” Technical Report CCL-2001-008, Georgia Institute of Technology, Atlanta, GA.
21.
Metcalfe
,
R. W.
,
Orszag
,
S. A.
,
Brachet
,
M. E.
,
Menon
,
S.
, and
Riley
,
J. J.
,
1987
, “
Secondary Instability of a Temporally Growing Mixing Layer
,”
J. Fluid Mech.
,
184
, pp.
207
–
243
.
22.
Riley, J. J., and Metcalfe, R. W., 1980, “Direct Numerical Simulation of a Perturbed, Turbulent Mixing Layer,” AIAA Paper No. 80-0274.
23.
Michalke
,
A.
,
1964
, “
On the Inviscid Instability of the Hyperbolic-Tangent Velocity Profile
,”
J. Fluid Mech.
,
19
, pp.
543
–
556
.
24.
Morse
,
A. P.
,
Whitelaw
,
J. H.
, and
Yianneskis
,
M.
,
1979
, “
Turbulent Flow Measurements by Laser-Doppler Anemometry in Motored Piston-Cylinder Assemblies
,”
J. Fluids Eng.
,
101
, pp.
208
–
216
.
25.
Haworth
,
D. C.
, and
Jansen
,
K.
,
2000
, “
Large-Eddy Simulation on Unstructured Deforming Meshes: Towards Reciprocating IC Engines
,”
Comput. Fluids
,
29
, pp.
493
–
524
.
26.
Weclas
,
M.
,
Melling
,
A.
, and
Durst
,
F.
,
1998
, “
Flow Separation in the Inlet Valve Gap of Piston Engines
,”
Prog. Energy Combust. Sci.
,
24
, pp.
165
–
195
.
27.
Nelson, C., and Menon, S., 1998, “Unsteady Simulations of Compressible Spatial Mixing Layers,” AIAA Paper No. 98-0786.
28.
Han, Z., Fan, L., and Reitz, R. D., 1997, “Multidimensional Modeling of Spray Atomization and Air-Fuel Mixing in a Direct-Injection Spark-Ignition Engine,” SAE Paper No. 970884.
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