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vasava February 27, 2013 06:59

UDF for calculating Oscillatory Shear Index (OSI)
I am writing a UDF for calculating Oscillatory Shear Index (OSI).

The definition of OSI can be found here (right side bottom of 2nd page)

Any hint or help about this?

Mailto October 15, 2013 08:53

I'm trying to do the same actually :)

djing October 22, 2014 07:02

osi in Fluent
hi dear colleague, to calculate the shear oscillation index in FLUENT I found these two links:,1074.0.html

but in the second link the colleague "infocfd" is about a UDF attached, but I canít download it ... if you can download the UDF or help me to understand the principle of calculated OSI on FLUENT please answer me ... thank you for your cooperation.

vasava October 23, 2014 01:46

Sorry but I cant download it either. Anyways I calculated OSI with matlab however visualization of the calculated is still an issue for us.

khuti October 29, 2015 04:24

Osi udf
1 Attachment(s)
Hello Guys,

I did some work in this field awhile ago, you can use the attached UDF I wrote for my uses back then.

Hope it helps, and yeah I know this one is an oldie...


vasava November 18, 2015 02:39

I will give it a try. Thanks Khuti!

dhplsy November 25, 2015 05:49

Thank you, Khuti.
I want to clarify if the OSI values are area-averaged.

khuti December 20, 2015 05:33

Hi Dhplsy,

Sorry for the delayed response.

The values that are being used in the calculation are taken from the Fluent raw data storage, so they are per cell face and averaged by the relevant cell face area.

Also please note, that you might want to delete some of the code related to the names of the UDM:

Set_User_Memory_Name(0, "uWSS");
Set_User_Memory_Name(1, "uWSSx");
Set_User_Memory_Name(2, "uWSSy");
Set_User_Memory_Name(3, "uWSSz");
Set_User_Memory_Name(4, "OSI");

( as I remember it caused some problems, hadn't the chance to figure out what was the problem)


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