Convection Term in Linearized Navier Stokes Equations

And901 · October 22, 2014, 10:53

Hi guys,

i'm trying to solve Linearized Navier Stokes Equations.
As we know the convective term is splitted in two parts:

[math] (U\ cdot \nabla) u + (u\ cdot \nabla) U [math]

where U is the base flux.

How can i write the second term in OpenFoam?

RodriguezFatz · October 23, 2014, 02:33

Andrea, this "two parts" splitting only comes up, if you write the equations in a non-conservative way. This is not done in openFOAM, it handles these terms conservatively (thus using tensors):
d/dt(rho U) + nabla dot (rho U U).
You can find how to write these terms for example in "PisoFoam.C":

Code:

 fvm::ddt(U) + fvm::div(phi, U)

October 22, 2014, 10:53	Convection Term in Linearized Navier Stokes Equations	#1
And901 New Member Andrea Join Date: Sep 2014 Posts: 17 Rep Power: 11	Hi guys, i'm trying to solve Linearized Navier Stokes Equations. As we know the convective term is splitted in two parts: [math] (U\ cdot \nabla) u + (u\ cdot \nabla) U [math] where U is the base flux. How can i write the second term in OpenFoam?

October 23, 2014, 02:33		#2
RodriguezFatz Senior Member Philipp Join Date: Jun 2011 Location: Germany Posts: 1,297 Rep Power: 26	Andrea, this "two parts" splitting only comes up, if you write the equations in a non-conservative way. This is not done in openFOAM, it handles these terms conservatively (thus using tensors): d/dt(rho U) + nabla dot (rho U U). You can find how to write these terms for example in "PisoFoam.C": Code: fvm::ddt(U) + fvm::div(phi, U) __________________ The skeleton ran out of shampoo in the shower.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
PISO algorithm for particular NS equation (special convection term)	Cyp	OpenFOAM Programming & Development	8	June 12, 2012 09:36
Navier stokes compresible viscid flow fea, somebody can help?	Jose Choy	Main CFD Forum	3	October 24, 2003 02:28
Navier Stokes Equations	J.J.	Main CFD Forum	2	June 29, 2000 09:31
help: I am trying to solve Navier Stokes compressible and viscid flow	Jose Choy	Main CFD Forum	2	May 18, 2000 05:45
Computational complexity of Navier Stokes equations	Marco Ellero	Main CFD Forum	5	May 5, 1999 21:07