For an impinging free shear layer having a fundamental instability frequency β, either a 0.5β component or components of ∼0.4β and ∼0.6β may be generated. Neither possibility results directly from vortex coalescence; instead, they are due to newly discovered patterns of vortex‐edge interaction.

1.
D. Rockwell and E. Naudascher, in Annual Review of Fluid Mechanics (Annual Reviews, Palo Alto, Calif., 1979), Vol. 11, p. 67.
2.
P.
Freymuth
,
J. Fluid Mech.
25
,
683
(
1966
).
3.
D.
Rockwell
and
W.
Niccolls
,
J. Basic Eng.
93
,
720
(
1972
).
4.
D.
Rockwell
,
J. Appl. Mech.
39
,
883
(
1972
).
5.
C. D.
Winant
and
F. K.
Browand
,
J. Fluid Mech.
63
,
237
(
1974
).
6.
A.
Roshko
,
AIAA J.
14
,
1349
(
1976
).
7.
D.
Rockwell
and
C.
Knisely
,
J. Fluid Mech.
93
,
413
(
1979
).
This content is only available via PDF.
You do not currently have access to this content.