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October 26, 2012, 00:02 |
boundary conditions in gambit
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#1 |
New Member
omar
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hi everybody
i'm trying to simulate a section of a gas turbine blade in fluent with cooling holes and for the geometry, mesh and boundary conditions i use gambit. The solution in fluent present a divergence, i think that some detail in the boundary conditions is wrong, i dont know if all the faces in my geometry must have a boundary condition (wall, interior, etc.) because i let some faces without boundary condition, also i dont know the difference between internal and interior bc. could u help me with these doubts please? thanks in advance |
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October 26, 2012, 13:55 |
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#2 |
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Maxime Perelli
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if all your domain is well connected; then you don t need to define interior or internal faces.
Also all the outer surfaces you didn t define will be regrouped as wall boundary. Now in fluent check if all the boundaries are present in the boundary panel and check if you have some shadow-wall
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October 26, 2012, 14:06 |
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#3 |
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omar
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Max, thanks for your response
then i guiess that a bad connection is the reason for my problems, how could i check the coneectiviti in gambit? i thinked that are well connected because all the domains sharing faces. thanks again bro |
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October 26, 2012, 14:14 |
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#4 |
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Maxime Perelli
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yes you cab check the connectivity of faces here http://202.118.250.111:8080/fluent/G...m#gc_speccolor
Surfaces should appear in pink if surfaces are connected. Another method for checking, is picking any volume and trying to MOVE it (not copy) If you can move it; then you have connectivity problem
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October 26, 2012, 14:23 |
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#5 |
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omar
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then maybe isn't connectivity because all my domains appear pinks. aditionally i tried to move all volumes and gambit dont let me. What do u think? is there another way to solve my problem?
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October 26, 2012, 14:29 |
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#6 |
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Maxime Perelli
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any wall-shadow in fluent BC-list?
If you stop the diverging solution, you can display the solution.Then display velocity and check if you don t have "wall" which stop the fluid flowing
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October 26, 2012, 16:20 |
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#7 |
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omar
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5 wall shadows.
i can't display velocity but i can display pressure and nothing interrupt the fluid flowing |
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October 27, 2012, 11:56 |
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#8 |
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Maxime Perelli
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display and locate wall shadows in fluent; and fix connectivity in gambit
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October 28, 2012, 00:28 |
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#9 |
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omar
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then the solution is fix the zones where wall shadows appear although there is heat transfer in those walls?
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October 28, 2012, 02:59 |
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#10 |
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Maxime Perelli
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post some pictures for understanding
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October 28, 2012, 16:43 |
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#11 |
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omar
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Hi Max
100000 thanks for your help a short description, the fluid enters the channel with a temperature a pressure and the cooling enters the plenum and goes out to cool the blade , then there is heat transfer in the blade, the first picture show the geometry and type zones, the second one show the areas that Fluent wall shadows |
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October 28, 2012, 16:51 |
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#12 |
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omar
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another doubt
the surfaces around the cooling holes must be wall oe interior? these surfaces belong to a solid and the cooling holes are fluids Last edited by galapago; October 28, 2012 at 18:40. |
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October 29, 2012, 03:06 |
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#13 |
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Maxime Perelli
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can you post first picture with shaded mode turned on?
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October 29, 2012, 13:46 |
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#14 |
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omar
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Hi Max
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October 30, 2012, 02:37 |
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#15 |
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Maxime Perelli
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I am not experienced with solid conduction, I recommend you: http://aerojet.engr.ucdavis.edu/flue...e567.htm#86350
Also I recommend you to simplify your physic and start without solid elements (no solid conduction). Then when you get congerged solution, increase complexity with solid conduction
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October 1, 2016, 09:49 |
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#16 | |
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suryateja
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Quote:
I am also working on this turbine blade cooling can you please tell me how the boundary conditions were taken.Can we give coolant mass flow inlet? for each cooling channel. |
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