CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > CFX

Writing Equation

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   May 20, 2014, 04:23
Default Writing Equation
  #1
New Member
 
Join Date: Mar 2014
Posts: 23
Rep Power: 12
brahmarishiraj is on a distinguished road
Dear Friends,

I have to calculate an expression which includes a term as written below:

|Ui-Vi|

Where Ui and Vi are velocity vectors of gas and particles.

Could you plz suggest me how to write these vectors in expression.
In results I found velocities in x, y and z direction available in drop down list.

Thanks
brahmarishiraj is offline   Reply With Quote

Old   May 20, 2014, 04:37
Default
  #2
Senior Member
 
Matthias Voß
Join Date: Mar 2009
Location: Berlin, Germany
Posts: 449
Rep Power: 20
mvoss is on a distinguished road
Subtract each component and save them in an Expression
myVelU = Fluid.Velocity u - Gas.Velocity u
myVelV =...
myVelW=...
and create a User Variable Vector from these 3 components.

Or you can skip the variable and apply the norm directly to you expression like
myVelNorm = sqrt((myVelU)^2 +....)
mvoss is offline   Reply With Quote

Old   May 20, 2014, 04:54
Default
  #3
New Member
 
Join Date: Mar 2014
Posts: 23
Rep Power: 12
brahmarishiraj is on a distinguished road
Quote:
Originally Posted by mvoss View Post
Subtract each component and save them in an Expression
myVelU = Fluid.Velocity u - Gas.Velocity u
myVelV =...
myVelW=...
and create a User Variable Vector from these 3 components.

Or you can skip the variable and apply the norm directly to you expression like
myVelNorm = sqrt((myVelU)^2 +....)

Dear Matthias,

Thank you for the reply, I will follow this:

"myVelNorm = sqrt((myVelU)^2 +....)"

At the same time could you plz suggest me on how to create a User Variable Vector?


Regards
brahmarishiraj is offline   Reply With Quote

Old   May 20, 2014, 05:00
Default
  #4
Senior Member
 
Matthias Voß
Join Date: Mar 2009
Location: Berlin, Germany
Posts: 449
Rep Power: 20
mvoss is on a distinguished road
In CFD-Post--> click on Create Variable (little alpha) and select vector instead of scalar.
mvoss is offline   Reply With Quote

Old   May 20, 2014, 05:04
Default
  #5
New Member
 
Join Date: Mar 2014
Posts: 23
Rep Power: 12
brahmarishiraj is on a distinguished road
Quote:
Originally Posted by mvoss View Post
In CFD-Post--> click on Create Variable (little alpha) and select vector instead of scalar.

Thank you again Matthias, its great.
brahmarishiraj is offline   Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Problem with cyclic boundaries in Openfoam 1.5 fs82 OpenFOAM 36 January 7, 2015 01:31
Calculation of the Governing Equations Mihail CFX 7 September 7, 2014 07:27
How to add bodyforce in momentum equation in viscoelasticFluidFoam? arshoon OpenFOAM Running, Solving & CFD 0 April 9, 2013 11:03
How to? Extra term in k-e equation. Implicit-Explicit be_inspired OpenFOAM Programming & Development 1 March 19, 2013 11:50
Poisson equation vs continuity equation DJ Main CFD Forum 1 August 5, 2004 21:01


All times are GMT -4. The time now is 23:41.