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sunilpatil April 10, 2013 13:20

Grid dependency study in building heat transfer
 
Hello sir,
I am doing my M Tech Project on building heat transfer.i have considered single room of dimensions 4*4*4 m.i am applying heat flux to the walls heat flux is varying with time.i have to run my simulation for 24 hours(Total time = 86400 s) my question is for grid dependency study either i have to very both time step size and grid size(space and time) or any one of them is enough because it takes too much of computational time even for time step of 10 s to solve for given total time
Results which i am interested are
1.Average room temperature
2.avg wall temperature

Thank you sir

imnull April 10, 2013 16:17

1 Attachment(s)
Quote:

Originally Posted by sunilpatil (Post 419695)
Hello sir,
I am doing my M Tech Project on building heat transfer.i have considered single room of dimensions 4*4*4 m.i am applying heat flux to the walls heat flux is varying with time.i have to run my simulation for 24 hours(Total time = 86400 s) my question is for grid dependency study either i have to very both time step size and grid size(space and time) or any one of them is enough because it takes too much of computational time even for time step of 10 s to solve for given total time
Results which i am interested are
1.Average room temperature
2.avg wall temperature

Thank you sir

see attached
Attachment 20646

ghorrocks April 10, 2013 21:00

This is why I strongly recommend using adaptive timestepping. Set adaptive time stepping to home in on 3-5 coeff loops per iteration, then yoru timestep is automatically calculated and you have one less variable to do a sensitivity analysis on.

sunilpatil April 11, 2013 02:10

Grid dependency
 
Hello sir,
Thank you for reply. i will try to run solver with adaptive time stepping as you suggested
Thank you sir
Sunil Patil

JuPa April 11, 2013 09:26

Quote:

Originally Posted by imnull (Post 419718)
see attached
Attachment 20646

Hi,

Where did you get the presentation from? What's the title of the presentation?

Thanks


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