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 bjk87 April 20, 2012 14:05

new to CFD and have a simple question about models

I am a 2nd year student at university studying engineering. I have absolutely no formal training or experience with CFD yet but I am interested in the aerodynamics field. My question is why is it common to use only half of the model for analysis? I was told that analyzing a symmetrical half of complex models reduces CPU power. Is that true? Thanks.

 cfdnewbie April 20, 2012 14:11

Quote:
 Originally Posted by bjk87 (Post 355891) I am a 2nd year student at university studying engineering. I have absolutely no formal training or experience with CFD yet but I am interested in the aerodynamics field. My question is why is it common to use only half of the model for analysis? I was told that analyzing a symmetrical half of complex models reduces CPU power. Is that true? Thanks.
well, the answer to your question is pretty straightforward: If the flow is symmetric about a certain axis, then yes, it is often common to model only half of the flow. Why? because the other half (the one you are not computing) would just give you the same results (mirrored) than the one you are actually modelling.

Two assumptions behind this:
a) the flow is indeed symmetric to a given axis/plane
b) your code has symmetry boundary conditions you can apply to the "cut"

Hope this clears it up!
Cheers!

 bjk87 April 20, 2012 14:16

Thank you. This was just one of the things I have been curious about.

 cfdnewbie April 20, 2012 14:18

Quote:
 Originally Posted by bjk87 (Post 355893) Thank you. This was just one of the things I have been curious about.