nonNewtonianIcoFoam equation

Svensen · March 4, 2015, 14:19

In the source of nonNewtonianIcoFoam solver I've found this equation:

fvVectorMatrix UEqn
(
fvm::ddt(U)
+ fvm::div(phi, U)
- fvm::laplacian(fluid.nu(), U)
- (fvc::grad(U) & fvc::grad(fluid.nu()))
);

It's all OK, except last operand "(fvc::grad(U) & fvc::grad(fluid.nu())"..

Why do we need to do bitwise AND with grad_U and grad_Nu ???

alexeym · March 4, 2015, 15:49

Hi,

You know, there is operator overloading, so & can be anything but bitwise AND.

sharonyue · March 5, 2015, 19:13

I hope this may help:http://www.cfd-online.com/Forums/ope...nu-grad-u.html

Svensen · March 6, 2015, 03:03

Thank you very much

March 4, 2015, 14:19	nonNewtonianIcoFoam equation	#1
Svensen Senior Member Join Date: Jan 2015 Posts: 150 Rep Power: 11	In the source of nonNewtonianIcoFoam solver I've found this equation: fvVectorMatrix UEqn ( fvm::ddt(U) + fvm::div(phi, U) - fvm::laplacian(fluid.nu(), U) - (fvc::grad(U) & fvc::grad(fluid.nu())) ); It's all OK, except last operand "(fvc::grad(U) & fvc::grad(fluid.nu())".. Why do we need to do bitwise AND with grad_U and grad_Nu ???

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March 4, 2015, 15:49		#2
alexeym Senior Member Alexey Matveichev Join Date: Aug 2011 Location: Nancy, France Posts: 1,938 Rep Power: 39	Hi, You know, there is operator overloading, so & can be anything but bitwise AND.

March 5, 2015, 19:13		#3
sharonyue Senior Member Dongyue Li Join Date: Jun 2012 Location: Beijing, China Posts: 849 Rep Power: 18	I hope this may help:http://www.cfd-online.com/Forums/ope...nu-grad-u.html

March 6, 2015, 03:03		#4
Svensen Senior Member Join Date: Jan 2015 Posts: 150 Rep Power: 11	Thank you very much