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January 30, 2013, 08:31 
Non Boussinesq approximation

#1 
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Hari
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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  
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Filippo Maria Denaro
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February 5, 2013, 09:04 
Non Boussinesq approximation

#3 
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Hari
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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 

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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 
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Hari
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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

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Jonas T. Holdeman, Jr.
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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  
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