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

Wrong Power Coefficient

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

LinkBack Thread Tools Search this Thread Display Modes
Old   August 10, 2018, 11:07
Default Wrong Power Coefficient
New Member
Manon Puech
Join Date: Aug 2018
Posts: 1
Rep Power: 0
Laypa is on a distinguished road

I am currently doing a Msc Thesis and my subject is: Cavitation Modelling Using CFD of a Rotating Propeller.
The project is based on the Southmapton experiment and I am trying to have the power coefficient with simulation in order to validate the model.
Unfortunately the Cp obtained is not correct: I end up with a Cp=0.27 instead of 0.42 with a speed water of 1.73m/s and a pitch angle for the blade of 20.
The formulas used are detailed in the txt file.
I already tried to refine the mesh and change some parameters but it is still not showing good results.
The software used is Ansys CFX and if you want to take a look at the setup and boundary conditions you can see them on the txt file also.

If you have some ideas why the results are not good I would be glad to have them.

And thank you for the time you took to read this post

Have a good day!
Attached Files
File Type: txt CFX_001.txt (46.3 KB, 5 views)
Laypa is offline   Reply With Quote

Old   August 11, 2018, 01:37
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,688
Rep Power: 143
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
Have you read the FAQ on accuracy?

Have you done a convergence criteria, mesh size and time step size sensitivity analysis?

Are you aware that cavitation modelling is very challenging and getting accurate results is not always possible? Cavitation models are not models where you should expect high accuracy.
Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.
ghorrocks is offline   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
Drag Coefficient Convergence Problem John FLUENT 18 June 24, 2023 09:22
Calculating the Cp (Power Coefficient ) for a cross flow vertical wind turbine AS_Aero CFX 13 February 14, 2018 16:57
Why Fluent give me wrong heat transfer coefficient? mariam.sara FLUENT 10 July 28, 2015 11:28
Automotive test case vinz OpenFOAM Running, Solving & CFD 98 October 27, 2008 08:43
power curve of windmills with CFD sayid FLUENT 2 March 28, 2007 09:55

All times are GMT -4. The time now is 09:57.