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 sasanghomi September 27, 2013 11:09

Hi foamers

I have two questions about swak4Foam :

1) I want to calculate radial velocity in an engine . Can I do this action by using swak4Foam? How? which type ? Can you write an example here?

2) How can I calculate an expression according to variables ? for example I want to use probe and I want to have sqrt(2*k/3) in a specific point versus time { k is turbulent energy }.How can I do that?

I appreciate any help,
Thanks and best regards,
Sasan.

 gschaider September 27, 2013 15:08

Quote:
 Originally Posted by sasanghomi (Post 453897) Hi foamers I have two questions about swak4Foam : 1) I want to calculate radial velocity in an engine . Can I do this action by using swak4Foam? How? which type ? Can you write an example here?
I've got to hand you back this question: can you be more specific? Do you want a new field, an average or what? You want it during the run or afterwards? And what is your definition of "radial velocity"?

Anyway: if you can write that definition as an expression on a piece of paper then you can calculate it in swak (probably in terms of velocity, position and the axis). Only thing you need to know is that & is the inner product of two vectors and ^ is the cross product (but you were probably aware of that if you looked at the Wiki-page and the incomplete reference guide http://openfoamwiki.net/images/d/db/...mReference.pdf)

Quote:
 Originally Posted by sasanghomi (Post 453897) 2) How can I calculate an expression according to variables ? for example I want to use probe and I want to have sqrt(2*k/3) in a specific point versus time { k is turbulent energy }.How can I do that?
That'd be a swakExpression-function object with valueType "set". There are examples for that in the Examples-folder of the distro and something like that is for instance explained in the presentation from the 6th workshop (linked from the Wiki-page)

Please have a look at the mentioned presentation and the reference guide before asking further. I only have a limited amount of time for supporting these things and every time I answer questions that are already documented I have less time to complete the actual documentation.

 sasanghomi September 28, 2013 05:44

Dear Bernhard ,

I have another question . Can you help me?
I want to calculate engine swirl :

That : {v= velocity & V=volume & r = position & Rs=swirl ratio &N=rpm}

I want to calculate Rs. Can I calculate Rs by using swak4Foam? I think swak doesn't have integration.Also I don't know how can I use r vector in swak !!! Can you guide me?

Best regards
Sasan.

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