The steady flow due to a nonuniform source in an otherwise uniform stream is studied, the source taking the form of an upstream-pointing and a downstream-pointing slender jet, or sheet-jet. The planar-model setting is described, along with applications, and then viscous flow computations are presented. The results show that the sheet-jet source together with the entrainment into the jets upstream and downstream induce an almost sink-like response in the overall flow, in contrast with the effects of a uniform source. The response yields a small eddy at the higher Reynolds numbers of the computations and suggests that large-scale eddies may occur for increased Reynolds numbers; yet the uniform-source model predicts the upstream stagnation point and some other features well.

1.
Davis, S. S., and Chang, I.-C., 1986, “The Critical Role of Computational Fluid Dynamics in Rotary-Wing Dynamics,” AIAA paper no. 86-0336.
2.
Strawn, R. C., and Caradonna, F. X., 1986, “Numerical Modeling of Rotor Flows With a Conservative Form of the Full-Potential Equations,” AIAA paper no. 86-0079.
3.
Seddon, J., 1990, Basic Helicopter Dynamics, BSP Prof. Books.
4.
Brouwer
,
H. H.
,
1992
, “
On the Use of the Method of Matched Asymptotic Expansions in Propellor Aeronautics and Astronautics
,”
J. Fluid Mech.
,
242
, pp.
117
144
.
5.
Landgrebe, A. J., 1994, “New Direction in Rotorcraft Computational Aerodynamics Research in the U.S.,” AGARD Rept. 1.
6.
Wake, B. E., and Baeder, J. D., 1994, “Evaluation of the TURNS Analysis for Hover Performance Prediction,” Am. Helic. Soc. Aeromech. Spec. Conf., Jan., San Fransisco, CA.
7.
Conlisk
,
A. T.
,
1994
, “
Modern Helicopter Aerodynamics
,”
Annu. Rev. Fluid Mech.
,
21
, pp.
515
567
.
8.
Smith
,
F. T.
, and
Timoshin
,
S. N.
,
1996a
, “
Blade-Wake Interactions and Rotary Boundary Layers
,”
Proc. R. Soc. London, Ser. A
,
A452
, pp.
1303
1329
.
9.
Smith
,
F. T.
, and
Timoshin
,
S. N.
,
1996b
, “
Planar Flows Past Thin Multi-Blade Configurations
,”
J. Fluid Mech.
,
324
, pp.
355
377
.
10.
Hawkings
,
D. L.
, and
Lowson
,
M. V.
,
1974
, “
Theory of Open Supersonic Rotor Noise
,”
J. Sound Vib.
,
36
, pp.
1
20
.
11.
Parry
,
A. B.
, and
Crighton
,
D. G.
,
1989
, “
Asymptotic Theory of Propellor Noise: 1. Subsonic Single-Rotation Propellor
,”
AIAA J.
,
27
, pp.
1184
1190
.
12.
Bowles
,
R. G. A.
, and
Smith
,
F. T.
,
2000a
, “
Interactive Flow Past Multiple Blades and Wakes
,”
Q. J. Mech. Appl. Math.
,
52
, pp.
1
45
.
13.
Bowles
,
R. G. A.
, and
Smith
,
F. T.
,
2000b
, “
Lifting Multi-Blade Flows with Interaction
,”
J. Fluid Mech.
,
415
, pp.
203
226
.
14.
Rayner
,
J. M. V.
,
1979
, “
A Vortex Theory of Animal Flight. Part 1. The Vortex Wake of a Hovering Animal
,”
J. Fluid Mech.
,
91
, pp.
697
730
.
15.
Bhattacharyya
,
S.
,
Dennis
,
S. C. R.
, and
Smith
,
F. T.
,
2001
, “
Separating Shear Flow Past a Surface-Mounted Blunt Obstacle
,”
J. Engg. Math.
,
39
, pp.
47
62
.
16.
Smith
,
F. T.
,
1985
, “
A Structure for Laminar Flow Past a Bluff Body at High Reynolds Number
,”
J. Fluid Mech.
,
155
, pp.
175
191
.
17.
Smith
,
F. T.
,
1986
, “
Concerning Inviscid Solutions for Large-Scale Separated Flows
,”
J. Eng. Math.
,
20
, pp.
271
292
.
18.
Peregrine
,
D. H.
,
1985
, “
A Note on the Steady High-Reynolds-Number Flow About a Circular Cylinder
,”
J. Fluid Mech.
,
157
, pp.
493
500
.
19.
Chernyshenko
,
S. I.
,
1998
, “
Asymptotic Theory of Global Separation
,”
Appl. Mech. Rev.
,
51
, pp.
523
536
.
20.
Purvis, R., 2002, “Rotor Blades and Ground Effect,” Ph.D. thesis, Univ. of London.
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