1 ERCOFTAC UFR 2-02: Flow past a square cylinder

1.1 Description

For a full description of the case see:
http://qnet-ercoftac.cfms.org.uk/index.php?title=Flow_past_cylinder

U_in = 0.54 m/s with 2% turbulence
Re_D = 22 000

Size of the square cylinder is 0.04 m wide and 0.392 m high.
Its situated in a tunnel with a width of 14D = 0.56 m.

1.2 Results

Experimental values are:
The Strouhal number is around 0.132
Drag coefficient is around 1.9-2.2

OpenFOAM results

The drag coefficient fluctuates a bit but after 5-6 seconds the average settles around 2-2.1.
The calculated Strouhal value in the above picture is approximately 0.136.

1.3 Notes

In the case directory there is a perl script called generateMeshDict.pl.
This script will generate the blockMeshDict file given input arguments. To see what they are just run it without any input arguments and it will write some helpful usage info.

If you want to run a 2D simulation just edit the generateMeshDict.pl and remove the comment infront of $nz.

my $nz = int(0.2*$H1/$dx) + 1;
#$nz = 1;

and change the wall bc to empty for lowerUpper patches

    print "    wall lowerUpper\n";

1.4 Download

The application to use is pisoFoam and the case can be downloaded here

1.5 References

This list only contains references that can be obtained for free and that are not subject to any copyright infringement...I hope.

It is just a small list that is by no means complete.

--Niklas 13:29, 24 April 2010 (UTC)

Benchmark ercoftac ufr2-02

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