
[Sponsors] 
January 30, 2013, 08:31 
Non Boussinesq approximation

#1 
New Member
Hari
Join Date: Jan 2013
Posts: 4
Rep Power: 5 
Hi,
I need to simulate natural convection in square cavity (bottom wall heated) without using Boussinesq approximation. I need to take the density changes into account with nonBoussinesq approximation. Can I solve this with an incompressible solver with treating density as constant? I need help about the formulation and way of solving. With regards, Hari 

January 30, 2013, 09:15 

#2  
Senior Member
Filippo Maria Denaro
Join Date: Jul 2010
Posts: 2,693
Rep Power: 33 
Quote:


February 5, 2013, 09:04 
Non Boussinesq approximation

#3 
New Member
Hari
Join Date: Jan 2013
Posts: 4
Rep Power: 5 
Thank you for replying. I need to develop a pressure based solver without boussinesq approximation. Is it possible to work on incompressible flows without treating density as constant.


February 5, 2013, 09:37 

#4 
Senior Member
Join Date: Jul 2009
Posts: 238
Rep Power: 11 
If the density can vary, then the flow by definition is not incompressible. however, you can develop segregated solvers for variable density flows. One example of such a solver can be found in a JCP paper by Hou and Mahesh. If you put their names into google scholar, the second or third entry will point you to a pdf version of that paper.


February 5, 2013, 10:42 
Non Boussinesq approximation

#5 
New Member
Hari
Join Date: Jan 2013
Posts: 4
Rep Power: 5 
Thankyou for replying.
I was referring to the following ASME J.heat transfer paper where they say the flow is incompressible with non boussinesq approximation in a differentially heated cavity. I have mentioned the details of the paper below. A Numerical Simulation of Combined Radiation and Natural Convection in a Differential Heated Cubic Cavity P. Kumar and V. Eswaran J. Heat Transfer,2010,Volume 132,Issue 2, 

February 5, 2013, 11:28 
Non Boussinesq approximation

#6 
Senior Member
Jonas T. Holdeman, Jr.
Join Date: Mar 2009
Location: Knoxville, Tennessee
Posts: 108
Rep Power: 10 
But doesn't "incompressible" just mean that the density is not a function of pressure? Isn't constant density just an additional simplification? I would think that an (idealized) incompressible fluid could still have the density a function of temperature or concentration. Isn't bouyancy just the result of density differences?


February 6, 2013, 10:01 

#7  
Senior Member

Quote:


Thread Tools  
Display Modes  


Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
InterFoam with boussinesq approximation  sinusmontis  OpenFOAM Running, Solving & CFD  1  November 24, 2016 21:07 
Boussinesq approximation, help please!  engahmed  FLUENT  0  May 20, 2010 11:25 
Question on boussinesq approximation  panos_metal  FLUENT  1  January 11, 2010 12:18 
boussinesq approximation  jamal  FLUENT  2  March 25, 2008 09:57 
Boussinesq approximation again  Gabriel  Main CFD Forum  3  May 11, 2000 09:24 