CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > FLUENT > Fluent UDF and Scheme Programming

CL-Drive: Custom Lift Control Function in Fluent 2022 R1

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   August 18, 2023, 04:41
Default CL-Drive: Custom Lift Control Function in Fluent 2022 R1
  #1
uvw
New Member
 
Join Date: Aug 2023
Posts: 2
Rep Power: 0
uvw is on a distinguished road
Greetings, CFD Online Community!

I'm reaching out to seek your guidance in developing a CL-Drive function within Fluent (2022 R1).
The primary aim of this CL-Drive function is to conduct simulations targeting a specific CL (Lift Coefficient) value, rather than requiring the traditional approach of specifying the AoA (Angle of Attack).
Through this function, the AoA will dynamically adjust across iterations to precisely achieve the designated CL target.
Your insights and expertise in this endeavor would be greatly appreciated.

The main steps of this CL-Drive function can be broken down as follows.
1- Specify a CL target:
This involves setting a desired value for the lift coefficient (CL) that you want the object to achieve during the simulation.

2- Estimation of dCL/dAlpha:
Here, I'm referring to the derivative of the lift coefficient with respect to the angle of attack (AoA). The derivative dCL/dAlpha indicates how much the lift coefficient changes in response to changes in the angle of attack.

3- Specify the maximum number of iterations between AoA updates:
This step involves setting a limit on how many iterations the simulation will perform before updating the angle of attack (AoA) value. By updating the AoA periodically, you can simulate the object's response to changes in its orientation with respect to the airflow.

4- Specify the number of iterations to evaluate dCL_dAlpha by using finite differences:
This refers to the method of numerically approximating the derivative dCL/dAlpha using finite differences. In a computational simulation, you can estimate derivatives by perturbing the input variable (in this case, the angle of attack) by a small amount and observing how the output variable (lift coefficient) changes. By comparing these changes, you can compute an approximation of the derivative. The number of iterations you specify will determine how many times you perform this perturbation and observation process to calculate the derivative accurately.

Thank you sincerely for your time and assistance. Your support is greatly appreciated.

Best regards
uvw
\m/
uvw is offline   Reply With Quote

Old   August 21, 2023, 05:27
Default
  #2
Senior Member
 
Alexander
Join Date: Apr 2013
Posts: 2,363
Rep Power: 34
AlexanderZ will become famous soon enoughAlexanderZ will become famous soon enough
are you going to make it in 3d?
__________________
best regards


******************************
press LIKE if this message was helpful
AlexanderZ is offline   Reply With Quote

Old   August 21, 2023, 07:21
Default
  #3
uvw
New Member
 
Join Date: Aug 2023
Posts: 2
Rep Power: 0
uvw is on a distinguished road
Quote:
Originally Posted by AlexanderZ View Post
are you going to make it in 3d?
Yes. The AoA will be defined in the XZ plane.
uvw is offline   Reply With Quote

Reply

Tags
angle of attack, cl target, cl-drive, lift coefficient, lift control


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
[mesh manipulation] RefineMesh Error and Foam warning jiahui_93 OpenFOAM Meshing & Mesh Conversion 4 March 3, 2018 12:32
heat transfer with RANS wall function, over a flat plate (validation with fluent) bruce OpenFOAM Running, Solving & CFD 6 January 20, 2017 07:22
is internalField(U) equivalent to zeroGradient? immortality OpenFOAM Running, Solving & CFD 7 March 29, 2013 02:27
OpenFOAM static build on Cray XT5 asaijo OpenFOAM Installation 9 April 6, 2011 13:21
Problem with compile the setParabolicInlet ivanyao OpenFOAM Running, Solving & CFD 6 September 5, 2008 21:50


All times are GMT -4. The time now is 01:25.