Defining Pressure outlet boundary condition in CFX

ROY4 · September 26, 2017, 15:40

Hello
I want to define pressure outlet boundary condition for a bubble column outlet in CFX. Does any one know which boundary condition is equivalent with pressure outlet?
I have chosen opening condition with static pressure but now it is asking me for volume fraction of air and water. What should I enter for air and water volume fractions in outlet?
Thanks in advance

evcelica · September 26, 2017, 17:11

Use outlet instead of opening if you want an outlet, and not an opening.

ROY4 · September 27, 2017, 07:04

And in outlet what should I give for pressure? Entrainment?or pressure direction or others?
Beside that what is the volume fraction of air and water in outlet?

ROY4 · September 27, 2017, 07:05

Quote:

Originally Posted by evcelica

Use outlet instead of opening if you want an outlet, and not an opening.

And in outlet what should I give for pressure? Entrainment?or pressure direction or others?
Beside that what is the volume fraction of air and water in outlet?

-Maxim- · September 27, 2017, 08:03

Did you do the tutorials? Those are some basic questions here...

ROY4 · September 27, 2017, 18:54

Quote:

Originally Posted by -Maxim-

Did you do the tutorials? Those are some basic questions here...

dear Maxim..

yeah, I did them as much as my time allowed..And by the way my question is basic because I am completely new in CFX. Sorry to take your time and I understand its kind of annoying, but I know nowhere else to ask my questions.

-Maxim- · September 28, 2017, 03:16

Here's the thing: it is usually faster to get the tutorials done and read the manual than writing here and wait/hope for an answer.
Furthermore, you have to consider that people help here for free and invest some of their free time. Answering basic questions is no fun, especially if we first have to guess what the person asking the questions actually means.

Okay. Next thing: please read this: Before you post a question please read this

Regarding your question: How should we know what to enter for water and vapor fractions if you don't give us details about your problem? A good description of your problem along with pictures of your problem would help.

For your question about what to set as pressure: please read the manual about "pressure" and "reference pressure" and decide what fits your problem. There are also tons of threads here in this forum discussing reference pressure etc.

September 26, 2017, 15:40	Defining Pressure outlet boundary condition in CFX	#1
ROY4 Member Roy Join Date: Sep 2017 Posts: 80 Rep Power: 9	Hello I want to define pressure outlet boundary condition for a bubble column outlet in CFX. Does any one know which boundary condition is equivalent with pressure outlet? I have chosen opening condition with static pressure but now it is asking me for volume fraction of air and water. What should I enter for air and water volume fractions in outlet? Thanks in advance Svetlana likes this.

September 26, 2017, 17:11		#2
evcelica Senior Member Erik Join Date: Feb 2011 Location: Earth (Land portion) Posts: 1,188 Rep Power: 23	Use outlet instead of opening if you want an outlet, and not an opening. Svetlana likes this.

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September 27, 2017, 07:04		#3
ROY4 Member Roy Join Date: Sep 2017 Posts: 80 Rep Power: 9	And in outlet what should I give for pressure? Entrainment?or pressure direction or others? Beside that what is the volume fraction of air and water in outlet?

September 27, 2017, 08:03		#5
-Maxim- Senior Member Maxim Join Date: Aug 2015 Location: Germany Posts: 413 Rep Power: 13	Did you do the tutorials? Those are some basic questions here...

September 28, 2017, 03:16		#7
-Maxim- Senior Member Maxim Join Date: Aug 2015 Location: Germany Posts: 413 Rep Power: 13	Here's the thing: it is usually faster to get the tutorials done and read the manual than writing here and wait/hope for an answer. Furthermore, you have to consider that people help here for free and invest some of their free time. Answering basic questions is no fun, especially if we first have to guess what the person asking the questions actually means. Okay. Next thing: please read this: Before you post a question please read this Regarding your question: How should we know what to enter for water and vapor fractions if you don't give us details about your problem? A good description of your problem along with pictures of your problem would help. For your question about what to set as pressure: please read the manual about "pressure" and "reference pressure" and decide what fits your problem. There are also tons of threads here in this forum discussing reference pressure etc.