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Old   October 20, 2016, 12:47
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I would like to ask question about transient solution.

The model which I work on reach steady state conditions after approxiamately 10800s. I added picture.

I analyzed as statedy state solution. But result is not same transient solution due to the time scale reach steady state is very large.

I will try to analyze as transient solution.

time step < (smallest mesh size/velocity)

time step < 0.0006s

For 10800s

Time step size 0.0005
Number of time step 21600000

This take long time. How can I solve this problem. Is there sımple way for this.

Can you advise me.

Thank you in advance

Best Regards
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Old   October 21, 2016, 02:00
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Try to do steady state with density and chose implicit approach
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Old   October 21, 2016, 05:35
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Thank you for your answer. Could you please explain a little more.
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Old   October 21, 2016, 06:56
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in implicit method, the solution progresses stably, hence possible to get the desired solution. Whatever may be the solution method, it is important to analyze with reference to the physics of the problem.

If you can send a brief writeup about you case, we can provide you the specific solution for your case. you can send text messages on:
http://workshopwale.com/ or can email at: adarsh@workshopwale.com

Quote:
Originally Posted by typhoon1010 View Post
I would like to ask question about transient solution.

The model which I work on reach steady state conditions after approxiamately 10800s. I added picture.

I analyzed as statedy state solution. But result is not same transient solution due to the time scale reach steady state is very large.

I will try to analyze as transient solution.

time step < (smallest mesh size/velocity)

time step < 0.0006s

For 10800s

Time step size 0.0005
Number of time step 21600000

This take long time. How can I solve this problem. Is there sımple way for this.

Can you advise me.

Thank you in advance

Best Regards
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Old   October 22, 2016, 05:04
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Quote:
Originally Posted by Workshop Technologies View Post
in implicit method, the solution progresses stably, hence possible to get the desired solution. Whatever may be the solution method, it is important to analyze with reference to the physics of the problem.

If you can send a brief writeup about you case, we can provide you the specific solution for your case. you can send text messages on:
http://workshopwale.com/ or can email at: adarsh@workshopwale.com
Thank you for your answer. I will try.

Best Regards.
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Old   October 22, 2016, 07:33
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Actually the thing is in implicit the number of equations to be solved is same as tge number of variable hence a constructive approach is made to all the equations but in explicit each variable have different equation easy to solve but explocit depends on time where as implicit is time independent
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Old   October 22, 2016, 11:16
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Quote:
Originally Posted by babanjaria View Post
Actually the thing is in implicit the number of equations to be solved is same as tge number of variable hence a constructive approach is made to all the equations but in explicit each variable have different equation easy to solve but explocit depends on time where as implicit is time independent

Thank you for your answer. I will try. and share result.
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