CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > ANSYS > CFX

Cel expressions for trasient problem

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Search this Thread Display Modes
Old   March 4, 2008, 10:03
Default Cel expressions for trasient problem
Posts: n/a
Hello all,

I'm new in CFD, I'm trying simulate a small wind turbine, where its velocity should be constant. But the velocity control is made from the queue of the turbine that has the capacity to blend and change the direction of incidence of the wind, which causes the desacceleration the turbine.

Right now, I'm in the first step of the problem. Using a value of wind, I want to find a constant velocity of the turbine in a transient system, changing the wind incidence's angle, if necessary, when the angular velocity of the turbine reaches a standard value.

I tried with cell expressions like Vel=Vel+∆V, where ∆V is calculated in each time step. I'm using torque to calculate the acceleration and I have an expression to change de wind incidence's angle. But an error message appears:

"A cyclic dependency between expressions has been detected while processing the expression assigned to 'Angular Velocity'. The cycle detected is as follows (there may be others): Vel -> Vel."

I tried to put others expressions but it didn't work… Can this problem only be solved with fortran routine or its possible with cel expressions?

Thanks for your help


  Reply With Quote


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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
UDF compiling problem Wouter Fluent UDF and Scheme Programming 6 June 6, 2012 04:43
area does not match neighbour by ... % -- possible face ordering problem St.Pacholak OpenFOAM 9 November 22, 2011 10:02
Problem in implementing cht tilek CFX 3 May 8, 2011 08:39
CEL problem juliom CFX 2 May 2, 2011 08:40
Adiabatic and Rotating wall (Convection problem) ParodDav CFX 5 April 29, 2007 19:13

All times are GMT -4. The time now is 13:48.