Hello, I try to simulate the vortex shedding frequency at a bluff body in a rectangular duct.I use the RSM Model with Enhanced Wall Treatment, PISO, Second order upwind and defined some vertixes around the bluff body, where I let me show the dynamic pressure (vertex average). In the insteady simulation i used about 20 Time Steps/expected period. With these settings I cant observe a periodic pressure characteristic. Does anyone know how to make the simulation show me the frequency? If anyone knows an Article, where the procedure for a similar problem is described it would help me a lot. It would be very helpful to know, where I can see the periodic pressure course and how high I can expect the amplitude to be. Best Regards Gerd Sattler

Hi Gerd,

where is the body positioned within the channel and what kind of body it is? There are some cases at which vortex shedding is suppresed at some degree (for example squar cyllinder in the proximity of a wall at a special size of a gap, or 3-dimensional very flat piramids mounted at a wall).

If it is relevant for you I can provide you with some links.

Regards Ianina

Hello Ianina, thanks for ur Mail It is a kind of triangular bluff body with the flat side in the direction of the inlet. Would be nice if u send me the links u have. So that I can decide which papers are relevant for my problem. I wish u a happy Christmas, Kind Regards Gerd Sattler

Hi Gerd,

some articles/links:

1. About suppression of vortex shedding from rectangular cyllinder: http://www.cfdsc.ca/english/bulletins/13/1309.html

2. 15th Australasian Fluid Mechanics Conference The University of Sydney, Sydney, Australia 13-17 December 2004 Flow Structure Around A Finite-Length Square Prism H.F. Wang, Y. Zhou, C.K. Chan, W. O. Wong

3. AUTHOR = "R. J. Martinuzzi and M. AbuOmar", TITLE = "Study of the flow around surface-mounted pyramids", JOURNAL = "Experiments in Fluids", VOLUME = "34", YEAR = "2003", PAGES = "379-389"

The last two articles i can send you by E-Mail.

Kind reagards

Ianina

One more article:

"Two-Dimensional Study of the Turbulent Wake Behind a Square Cylinder Subject to Uniform Shear"

A. K. Saha G. Biswas K. Muralidhar

in: Journal of Fluids Engineering SEPTEMBER 2001, Vol. 123, p. 595-603

Can be relevant for you : flow at RE = 20 000

Hope it helps

Ianina