# [GAMBIT] Problem with split option

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 January 21, 2014, 01:45 #21 Super Moderator     Maxime Perelli Join Date: Mar 2009 Location: Switzerland Posts: 3,291 Rep Power: 38 did you see this tutorial: https://www.sharcnet.ca/Software/Flu.../tg/node23.htm I think you have to set your periodic BC with mass flow rate (as you already did), but I am not agree as you writing that du/dy= 0. If you impose the massflow, then in the middle (0.5*l1) of your domain you have the critical section and your fluid will accelerate for maintaining same massflow. Do you already have some results? can you display the velocity distribution? __________________ In memory of my friend Hervé: CFD engineer & freerider

 January 21, 2014, 03:17 Concept of periodic conditions #22 Member   Join Date: Dec 2013 Posts: 53 Rep Power: 9 Hi Thanks for the response. 1.I have gone through the tutorial you suggested before starting my work. 2.I have done the tutorial for the developed flow through pipes. for both of the above cases,same periodic conditions with pressure drop will be given. In the second case,there is no change in the velocity profile (du/dy=0) after simulation. In the first case,du/dy should not be the same.But we follow the same procedure of giving periodic conditions as that was done for case2. How are this happening?

 January 21, 2014, 03:43 #23 Super Moderator     Maxime Perelli Join Date: Mar 2009 Location: Switzerland Posts: 3,291 Rep Power: 38 display velocity and pressure distribution __________________ In memory of my friend Hervé: CFD engineer & freerider

January 21, 2014, 04:49
Concept of periodic conditions
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Hi
Thanks for the reply.Please find attached the contours of X velocity,and pressure. mass flow rate is 0.0003575kg/s
Attached Files
 tecplot.docx (33.8 KB, 1 views)

 January 21, 2014, 05:12 #25 Super Moderator     Maxime Perelli Join Date: Mar 2009 Location: Switzerland Posts: 3,291 Rep Power: 38 if you set the max velocity very low in the scale , do you see any velocity between all your squares? __________________ In memory of my friend Hervé: CFD engineer & freerider

 January 22, 2014, 04:07 Concept of periodic conditions #26 Member   Join Date: Dec 2013 Posts: 53 Rep Power: 9 Hi MAx, How can we use same periodic conditions to 1.flow with a pressure drop,which is geometrically periodic in nature,and is not fully developed(like the model in fig 4.2 which I use for simulation). and also to 2.Flow with a pressure drop,and fully developed flow(like fully developed flow through circular pipe) Iam getting confused.

 January 22, 2014, 04:44 #27 Super Moderator     Maxime Perelli Join Date: Mar 2009 Location: Switzerland Posts: 3,291 Rep Power: 38 I don't know. I am not experienced with periodic flow. Did you check if you get velocity distribution between your solid squares ? __________________ In memory of my friend Hervé: CFD engineer & freerider

 January 22, 2014, 05:00 #28 Member   Join Date: Dec 2013 Posts: 53 Rep Power: 9 Max, I also have one more doubt.. I am studying the heat transfer rate within an isothermal medium which is not moving(still) and it s at temp T1. The medium is confined within two large black isothermal walls of temp T2. If we have to specify a wall as isothermAL, we can just give the value of the temperature in boundary conditions>>edit>>thermal >>thermal conditions>>temperature.... Am i right?? And if we want to specify a medium (fluid /solid) as isothermal, how to give a specified temperature for that? Because in boundary conditions panel, for solid or fluid, we can only edit the name and nothing else.. plssssssssssss tell me how to specify a still medium as isothermal... ?? Do we have to specify it in reference values section ?? or do we have to give it under cell zone conditions>>edit>>Fixed values>>Temperature ??? I tried it with fixed value once an as i am wrking in radiation heat transfer problems, i dont think I am right... plsssssssssssss give me ur suggestions, max... I badly need it..

 January 22, 2014, 05:11 #29 Super Moderator     Maxime Perelli Join Date: Mar 2009 Location: Switzerland Posts: 3,291 Rep Power: 38 I suggest you to open a new thread in the fluent subforum You will have more chance to have answer of your thermal question __________________ In memory of my friend Hervé: CFD engineer & freerider

 March 25, 2014, 00:00 pressure drop in periodic flow #30 Member   Join Date: Dec 2013 Posts: 53 Rep Power: 9 Hi Max, I have simulated flow over solids through a channel.I have applied periodic boundary conditions at the inlet and exit of the pipe. Can I use the pressure drop indicated in periodic boundary conditions menu after the convergence of the case as pressure drop /L for my further work? Can you please clarify.

 Tags gambit, geometry