Inlet Speed

rouco75 · March 12, 2018, 19:02

Hi,
I would like to make a simulation where my inlet velocity goes from 0 to x m/s, i meant like a pulse of air, or like static structural when you can input a ramped force.
I am studying and i dont know how to do that so i am searching for help.
PD: Forgive me if this shouldnt be asked here.

LuckyTran · March 13, 2018, 19:19

Open the Fluent User's Guide (open the help and go to the user's guide). Or you can just search the help.

In v17 you can find an example n 6.6.5 Defining Transient Cell Zone and Boundary Conditions and 6.6.5.1 Standard Transient Profiles. If you have a different version it should be somewhere around there. The profile is a text file which looks like this:

Code:

profilename 2 3 0
time u
1 10
2 20
3 30

The 2 means 2 variable columns (time and u). The 3 means number of data points (3 in this example: [1 10] [2 20] and [3 30]). The 0 is the false flag for periodic. If you had a periodic profile you would make this 1 for true. Fluent interpolates so you only need key points for ramps.

You read this file into your case and then you can assign it as a boundary condition.

If this isn't powerful enough then you can try a udf. There's also an example of how to do this but in the Customization Manual. Search for DEFINE_PROFILE

rouco75 · March 13, 2018, 19:39

Thank you so much, you were very helpfull

March 12, 2018, 19:02	Inlet Speed	#1
rouco75 New Member Adrian Rouco Join Date: Mar 2018 Posts: 13 Rep Power: 8	Hi, I would like to make a simulation where my inlet velocity goes from 0 to x m/s, i meant like a pulse of air, or like static structural when you can input a ramped force. I am studying and i dont know how to do that so i am searching for help. PD: Forgive me if this shouldnt be asked here.

March 13, 2018, 19:19		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,761 Rep Power: 66	Open the Fluent User's Guide (open the help and go to the user's guide). Or you can just search the help. In v17 you can find an example n 6.6.5 Defining Transient Cell Zone and Boundary Conditions and 6.6.5.1 Standard Transient Profiles. If you have a different version it should be somewhere around there. The profile is a text file which looks like this: Code: profilename 2 3 0 time u 1 10 2 20 3 30 The 2 means 2 variable columns (time and u). The 3 means number of data points (3 in this example: [1 10] [2 20] and [3 30]). The 0 is the false flag for periodic. If you had a periodic profile you would make this 1 for true. Fluent interpolates so you only need key points for ramps. You read this file into your case and then you can assign it as a boundary condition. If this isn't powerful enough then you can try a udf. There's also an example of how to do this but in the Customization Manual. Search for DEFINE_PROFILE

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March 13, 2018, 19:39		#3
rouco75 New Member Adrian Rouco Join Date: Mar 2018 Posts: 13 Rep Power: 8	Thank you so much, you were very helpfull