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February 20, 2008, 04:56 |
Hello
First post on the mes
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#1 |
Member
Juho Peltola
Join Date: Mar 2009
Location: Finland
Posts: 89
Rep Power: 17 |
Hello
First post on the message board. I've only begun looking into OpenFOAM a few weeks ago. I'm trying to simulate a intake plenum of a car and I'm using rhoTurbFoam. My problem is how to define the time dependant boundary conditions for the outlets to each cylinder. In a test case I currently have defined them as: =============================================== 0/U: out1 { type inletOutlet; inletValue uniform (0 0 0); value uniform (0 0 0); } inlet { type pressureInletOutletVelocity; phi phi; value uniform (0 0 0); } 0/p: out1 { type timeVaryingUniformFixedValue; timeDataFileName ".../out1p.dat"; value uniform 100000; } inlet { type totalPressure; U U; phi phi; rho none; psi none; gamma 1; p0 uniform 100000; value uniform 100000; } =============================================== The out1.dat has a period of constant inlet pressure followed by a sine curve of a lower pressure. This setup gives something resembling the boundary conditions I want but it's not really correct. I would like to change the type of the boundary depending on time: =============================================== T1: =============================================== p: out1 { type timeVaryingUniformFixedValue; timeDataFileName ".../out1p.dat"; value uniform 100000; } U: out1 { type zeroGradient; } =============================================== T2: =============================================== p: out1 { type zeroGradient } U: out1 { type fixedValue; value uniform (0 0 0); } =============================================== Is there an easy way to accomplish this? Or is there a better way to approach the issue all together? I would greatly appreciate any help or guidance! Juho |
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February 21, 2008, 03:17 |
At first glance, it would seem
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#2 |
Senior Member
Mark Olesen
Join Date: Mar 2009
Location: https://olesenm.github.io/
Posts: 1,715
Rep Power: 40 |
At first glance, it would seem that you need to write a time-varying mixed boundary condition and use the mixing parameter to switch between the value and the gradient.
The example input file might look like this: // time fraction refValue refGradient // using 10m/s ( 0.1 1 10 0) ... // using zero-gradient ( 0.2 0 10 0) /mark |
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February 21, 2008, 10:21 |
Thank you!
I'll start looki
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#3 |
Member
Juho Peltola
Join Date: Mar 2009
Location: Finland
Posts: 89
Rep Power: 17 |
Thank you!
I'll start looking into writing a timeVaryingMixed boundary condition. Let's see how it goes... Juho |
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December 8, 2008, 05:03 |
Hi, Juho
I'm also intereste
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#4 |
Member
florian
Join Date: Mar 2009
Location: Mannheim - Vincennes - Valenciennes, Deutchland - France
Posts: 34
Rep Power: 17 |
Hi, Juho
I'm also interested on timeVaryingMixed boundary condition. Have you successfully done it ?? Florian |
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February 17, 2010, 01:41 |
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#5 | |
Member
Join Date: Mar 2009
Location: Sydney, New South Wales, Australia
Posts: 42
Rep Power: 17 |
Quote:
Hi Juho, Floooo, Did you get anywhere with your Boundary Condition problems? I too am looking at developing a time based BC that changes from an inlet to a wall at a specified time during the run. I am looking at using an IF, THEN, ELSE statement within the condition code to try and get it working, however so far I have had no luck. If you have had any success with your problems, then I would love to hear about it! R |
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May 26, 2019, 20:04 |
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#6 |
New Member
Nadun Palmada
Join Date: Apr 2017
Posts: 15
Rep Power: 9 |
Hi rassilon
Did you manage to figure out how to achieve this? Thanks Nadun |
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