Numerical simulations of the transient flow of helium injected into an established background flow of nitrogen were carried out to identify the dominant features of the transient mixing process between these two dissimilar gases. The geometry of interest is composed of two helium slots on either side of a central nitrogen channel feeding into a rectangular mixing chamber that was experimentally designed to give “two-dimensional” flow. Simulations were accomplished on both two- and three-dimensional grids. The 3D solutions employ an unsteady DES approach, while the 2D results are based upon a reduced dimension, “DES-like” method. Results are compared with quantitative experimental measurements of species distributions both in terms of contour plots and local point measurements. The 2D solutions give a reasonable qualitative picture of the transient mixing process in the center of the chamber while also providing quantitative estimates of representative characteristic times for guiding the 3D calculations. The 3D solutions give a reasonable approximation to span-wise variations observed in the experiment.

References

References
1.
Jahnke
,
S.
,
Kornev
,
N.
,
Tkatcheno
,
I.
,
Hassel
,
E.
, and
Leder
,
A.
, 2005, “
Numerical study of influence of different parameters on mixing in a coaxial jet mixer using LES
,”
Heat Mass Transfer
,
41
, pp.
471
481
.
2.
Feng
,
H.
,
Olsen
,
M. G.
,
Liu
,
Y.
,
Fox
,
R. O.
, and
Hill
,
J. C.
, 2005, “
Investigation of turbulent mixing in a confined planar-jet reactor
,”
AICHE J.
,
51
(
10
), pp.
2649
2664
.
3.
Feng
,
H.
,
Olsen
,
M. G.
,
Hill
,
J. C.
, and
Fox
,
R. O.
, 2007, “
Simultaneous velocity and concentration field measurements of passive scalar in a confined rectangular jet
,”
Exp. Fluids
42
, pp.
847
862
.
4.
Stanley
,
S. A.
,
Sarkar
,
S.
, and
Mellado
,
J. P.
, 2002, “
A study of the flowfield evolution and mixing in a planar turbulent jet using direct numerical simulation
,”
J Fluid Mech
450
, pp.
377
407
.
5.
Johnson
,
B. V.
Bennett
,
J. C.
, 1981, Mass and momentum turbulent transport experiments with confined coaxial jets. NASA Contractor Rep. NASA, CR-165574, UTRC Rep R81-915540-9.
6.
Durst
,
F.
,
Pereira
,
J. F. C.
, and
Tropea
,
C.
, 1993, “
The plane symmetric sudden-expansion flow at low Reynolds numbers
,”
J. Fluid Mech.
248
, pp.
567
581
.
7.
Fearn
,
R. M.
,
Mullin
,
T.
, and
Cliffe
,
K. A.
, 1990, “
Nonlinear flow phenomena in a symmetric ducts with sudden expansion
,”
J. Fluid Mech
211
, pp.
595
608
.
8.
De Zilwa
,
S. R. N.
,
Khezzar
,
L.
, and
Whitelaw
,
J. H.
, 2000, “
Flows through plane sudden-expansions
,”
J. Numer. Meth. Fluids
32
, pp.
313
329
.
9.
Balarac
,
G.
,
Si-Ameur
,
M.
,
Lesieur
,
M.
, and
Metais
,
O.
, 2007, “
Direct numerical simulations of high velocity ratio coaxial jets: mixing properties and influence of upstream conditions
,”
J. Turbul.
8
(
22
) pp.
1
27
.
10.
Tkatchenko
,
I.
,
Kornev
,
N.
,
Jahnke
,
S.
,
Steffen
,
G.
, and
Hassel
,
E.
, 2007, “
Performance of LES and RANS models for simulation of complex flows in a coaxial jet mixer
,”
Flow Turbul. Combust.
78
, pp.
111
127
.
11.
Akselvoll
,
K.
, and
Moin
,
P.
, 1996, “
Large-eddy simulation of turbulent confined coannular jets
,”
J. Fluid Mech.
315
, pp.
387
411
.
12.
Baloch
,
A.
,
Townsend
,
P.
, and
Webster
,
M. F.
, and 1995,
On two- and three-dimensional expansion flows
.
J. Comp. Fluids
24
(
8
) pp.
863
882
.
13.
Tseng
,
C. C.
,
Kulatilaka
,
W. D.
, and
Lucht
,
R. P.
, 2006, “
Laser imaging of transient mixing in a simulated chamber
,” AIAA Paper No. 2006-4530, July 2006.
14.
Tseng
,
C. C.
,
Kulatilaka
,
W. D.
,
Bhuiyan
,
A.
,
Merkle
,
C. L.
, and
Lucht
,
R. P.
2007,
Laser imaging of transient injection and mixing in a simulated rocket chamber
. AIAA Paper No. 2007-5589, July 2007.
15.
Tseng
,
C. C.
,
Voytovych
,
D. M.
,
Kulatilaka
,
W. D.
,
Bhuiyan
,
A. H.
,
Lucht
,
R. P.
,
Merkle
,
C. L.
,
Hulka
,
J. R.
, and
Jones
,
G. W.
, 2009, “
Structure and mixing of a transient flow of helium injected into an established flow of nitrogen: two dimensional measurement and simulation
,”
Exp. Fluids
,
46
, pp.
559
575
.
16.
Travin
,
A.
,
Shur
,
M.
,
Strelets
,
M.
, and
Spalart
,
P. R.
, 2000, Physical and Numerical Upgrades in the Detached-Eddy Simulation of Complex Turbulent Flows. In 412 EUROMECH Colloquium on LES of Complex Transitional and Turbulence Flows, Munich, Oct. 2000, Book of Abstracts.
17.
Menter
,
F. R.
, and
Egorov
,
Y.
, 2005, “
A Scale-Adaptive Simulation Model Using Two-Equation Models
,” AIAA Paper 2005-1095.
18.
Basu
,
D.
,
Hamed
,
A.
, and
Das
,
K.
, 2005, DES, Hybrid RANS/LES and PANS Models for Unsteady Separated Turbulent Flow Simulations. FEDSM2005-77421, Proceedings of FEDSM’05.
19.
Baurle
,
R. A.
,
Tam
,
C.-J.
,
Edwards
,
J. R.
, and
Hassan
,
H. A.
, 2003, “
Hybrid Simulation Approach for Cavity Flows: Blending, Algorithm, and Boundary Treatment Issues
,”
AIAA J.
,
41
(
8
), pp.
1463
1480
.
20.
Wilcox
,
D. C.
, 1998,
Turbulence Modeling for CFD
,
2nd Ed.
DCW Industries
,
La Canada
.
21.
Li
,
D.
,
Xia
,
G.
,
Merkle
,
C. L.
, 2003, “
Analysis of real fluid flows in converging diverging nozzles
,” AIAA Paper 2003-4132.
22.
Li
,
D.
,
Sankaran
,
V.
,
Merkle
,
C. L.
,
Lindau
,
J.
, 2005, “
A unified computational formulation for multi-component and multi-phase flows
,” AIAA Paper 2005-1391.
23.
Lian
,
C.
,
Xia
,
G.
, and
Merkle
,
C. L.
, 2009, “
Solution-Limited Time Stepping to Enhance Reliability in CFD Applications
,”
J. Comput. Phys.
228
, pp.
4836
4857
.
24.
Lian
,
C.
, “
Solution-Limited Time Stepping Method and Numerical Simulation of Single-Element Rocket Engine Combustor
,” Major Professor: Charles L. Merkle, Ph.D. Dissertation, School of Mechanical Engineering, Purdue University, West Lafayette, August 2009.
25.
Lian
,
C.
,
Merkle
,
C. L.
, and
Xia
,
G.
, 2010, “
Flowfield Initialization and Approach to Stationary Conditions in Unsteady Combustion Simulations
,”
Comput. Fluids
39
, pp.
310
323
(2010).
26.
Lian
,
C.
Xia
,
G.
, and
Merkle
,
C. L.
, “
Effects of Back-Step Height and Recirculation Zones on Unsteady Mixing and Combustion
,” The 39th AIAA Fluid Dynamics Conference, June 22–25, 2009, San Antonio, TX.
You do not currently have access to this content.