This paper reports on the experimental investigation of the flow inside a low aspect ratio (length less than the reattachment length of separated flow) dump combustor with a tapered exit. The flow field in the combustor is evaluated using wall pressure and velocity measurements at varying flow Reynolds numbers. The mean velocity and turbulence variation closer to the wall of the combustor was found to be different from that at other radial locations due to the presence of recirculation and possible thickening of the shear layer caused by a decrease in the strength of the potential core. The power spectral study of the wall pressure and velocity fluctuations suggested the dominant presence of acoustic perturbations with amplitude modulation of such perturbations due to viscous dissipation in the shear layer.

References

References
1.
Robinson
,
S. K.
,
1991
, “
Coherent Motions in the Turbulent Boundary Layer
,”
Ann. Rev. Fluid Mech.
,
23
, pp.
601
639
.10.1146/annurev.fl.23.010191.003125
2.
Schadow
,
K. C.
,
Gutmark
,
E.
, and
Wilson
,
K. J.
,
1992
, “
Active Combustion Control in a Coaxial Dump Combustor
,”
Comb. Sci. Technol.
,
81
, pp.
285
300
.10.1080/00102209208951807
3.
Rhode
,
D. L.
,
Lilley
,
D. G.
, and
McLaughlin
,
D. K.
,
1983
, “
Mean Flow Fields in Axisymmetric Combustor Geometries With Swirl
,”
AIAA J.
,
21
(
4
), pp.
593
600
.10.2514/3.60127
4.
Escudier
,
M. P.
, and
Keller
,
J. J.
,
1985
, “
Recirculation in Swirling Flow: Manifestation of Vortex Breakdown
,”
AIAA J.
,
23
(
1
), pp.
111
116
.10.2514/3.8878
5.
Joos
,
F.
, and
Vortmeyer
,
D.
,
1986
, “
Self-Excited Oscillations in Combustion Chambers With Premixed Flames and Several Frequencies
,”
Combust. Flame
,
65
, pp.
253
262
.10.1016/0010-2180(86)90039-8
6.
Schadow
,
K. C.
,
Wilson
,
K. J.
, and
Gutmark
,
E.
,
1987
, “
Characterization of Large-Scale Structures in a Forced Ducted Flow With Dump
,”
AIAA J.
,
25
(
9
), pp.
1164
1170
.10.2514/3.9763
7.
Yu
,
K.
,
Wilson
,
K. J.
,
Parr
,
T. P.
,
Smith
,
R. A.
, and
Schadow
,
K. C.
,
1996
, “
Characterization of Pulsating Spray Droplets and Their Interaction With Vortical Structures
,” AIAA Paper No. 96-0083.
8.
Schadow
,
K. C.
,
Yu
,
K.
,
Parr
,
T. P.
, and
Wilson
,
K. J.
,
1997
, “
Active Combustion Control With Pulsed Fuel Injection
,” ISABE Paper No. 97-7153.
9.
Drewry
,
J. E.
,
1978
, “
Fluid Dynamic Characterization of Sudden-Expansion Ramjet Combustor Flowfields
,”
AIAA J.
,
16
(
4
), pp.
313
319
.10.2514/3.60894
10.
Viets
,
H.
, and
Drewry
,
J. E.
,
1981
, “
Quantitative Prediction of Dump Combustor Flowfields
,”
AIAA J.
,
19
(
4
), pp.
484
491
.10.2514/3.7857
11.
Yang
,
B. T.
, and
Yu
,
M. H.
,
1983
, “
The Flow Field in a Suddenly Enlarged Combustion Chamber
,”
AIAA J.
,
21
(
1
), pp.
92
97
.10.2514/3.8033
12.
Usui
,
H.
, and
Sano
,
Y.
,
1989
, “
Recirculating Flow in a Confined Space With Axisymmetric Sudden Expansion Followed by Conical Contraction
,”
J. Chem. Eng. Jpn.
,
22
(
1
), pp.
1
5
.10.1252/jcej.22.1
13.
Farabee
,
T. M.
, and
Casarella
,
M. J.
,
1991
, “
Spectral Features of Wall Pressure Fluctuations Beneath Turbulent Boundary Layers
,”
Phys. Fluids
,
3
(10)
, pp.
2410
2420
.10.1063/1.858179
14.
Simpson
,
R. L.
,
Ghodbane
,
M.
, and
McGrath
,
B. E.
,
1987
, “
Surface Pressure Fluctuations in a Separating Boundary Layer
,”
J. Fluid Mech.
,
177
, pp.
167
186
.10.1017/S0022112087000909
15.
Bull
,
M. K.
,
1996
, “
Wall Pressure Fluctuations Beneath Turbulent Boundary Layers: Some Reflections on Forty Years of Research
,”
J. Sound Vib.
,
190
(
3
), pp.
299
315
.10.1006/jsvi.1996.0066
16.
Menon
,
S.
, and
Wen
,
H. J.
,
1990
, “
Numerical Simulation of Oscillatory Cold Flows in an Axisymmetric Ramjet Combustor
,”
J. Propul. Power
,
6
(
5
), pp.
525
534
.10.2514/3.23252
17.
McManus
,
K. R.
,
Vandsburger
,
U.
, and
Bowman
,
C. T.
,
1990
, “
Combustor Performance Enhancement Through Direct Shear Layer Excitation
,”
Combust. Flame
,
82
, pp.
75
92
.10.1016/0010-2180(90)90079-7
18.
Schadow
,
K. C.
,
Wilson
,
K. J.
, and
Gutmark
,
E.
,
1987
, “
Characterization of Large-Scale Structures in a Forced Flow With Dump
,”
AIAA J.
,
25
(
9
), pp.
1164
1170
.10.2514/3.9763
19.
Gutmark
,
E.
, and
Ho
,
C. M.
,
1983
, “
Preferred Modes and the Spreading Rate of the Jets
,”
Phys. Fluids
,
26
(
10
), pp.
2932
2938
.10.1063/1.864058
20.
Nigam
,
S.
,
Ahmed
,
D.
, and
Kushari
,
A.
,
2009
, “
Macroscopic Flow Behavior in a Low Aspect Ratio Dump Combustor With Tapered Exit
,”
Int. J. Turbo Jet Engines
,
26
(
1
), pp.
19
31
.10.1515/TJJ.2009.26.1.19
21.
Yadav
,
N. P.
, and
Kushari
,
A.
,
2009
, “
Vortex Combustion in Low Aspect Ratio Dump Combustor With Tapered Exit
,”
Energy Convers. Manage.
,
50
(
12
), pp.
2983
2991
.10.1016/j.enconman.2009.07.017
22.
Yadav
,
N. P.
, and
Kushari
,
A.
,
2010
, “
Effect of Swirl on Turbulent Behaviour of a Dump Combustor Flow
,”
Proc. IMechE Part G: J. Aerosp. Eng.
,
224
(
6
), pp.
705
717
.10.1243/09544100JAERO627
23.
Moffat
,
R. J.
,
1988
, “
Describing the Uncertainties in the Experimental Results
,”
Exp. Therm. Fluid Sci.
,
1
, pp.
3
17
.10.1016/0894-1777(88)90043-X
24.
Tran
,
N.
,
Ducruix
,
S.
, and
Schuller
,
T.
,
2009
, “
Damping Combustion Instabilities With Perforates at the Premixer Inlet of a Swirled Burner
,”
Proc. Combust. Inst.
,
32
(
2
), pp.
2917
2924
.10.1016/j.proci.2008.06.123
You do not currently have access to this content.