CFD Online Logo CFD Online URL
Home > Forums > General Forums > Main CFD Forum

Skin Friction Coefficient in Ansys CFX-Post

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

Like Tree1Likes
  • 1 Post By FreeFlyer

LinkBack Thread Tools Search this Thread Display Modes
Old   July 17, 2022, 06:57
Default Skin Friction Coefficient in Ansys CFX-Post
New Member
Join Date: Jul 2022
Posts: 1
Rep Power: 0
FreeFlyer is on a distinguished road
Hi there,

I'm currently writing a thesis about the development of a propeller design for an aircraft. To evaluate my design I did a recalculation with Ansys CFX 20R1. Now, analysing the result with CFX-Post, I want to know where flow separation takes place on the blade's surface. Apparently you normally use the skin friction coefficient C_f as an indicator. The problem is that I can't find it in even though Ansys lists it in its CFX-Post manual in the variable list. As a workaround I defined the expression for the skin friction coefficient: "Wall Shear/(o.5*Density*Velocity^2)", and plotted it over the blade's surface. But the result was all positive even though I know from plotting streamlines and vectors that there is flow separation happening and so the coefficient should be negative.
My next step in troubleshooting was to plot just the Wall Shear - if I understand it correctly it's the parameter which causes the skin friction coefficient to become negative. But also the Wall Shear is all positive.
So I wonder if there's a direct way of plotting the skin friction coefficient or if I could work around it with some formula? If it's just possible using a formula I wonder if I already use the right one and if I did some error? Is my understanding of the variable Wall Shear wrong?

I would be glad for every hint,
ypaaxx likes this.
FreeFlyer is offline   Reply With Quote


ansys, cfx-post, skin frictin coefficient, wall shear

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
Calculating tangential skin friction coefficient on an airfoil imandralis SU2 0 May 14, 2021 06:02
Ansys SIG$ILL error loth ANSYS 3 December 24, 2015 06:31
Mean skin friction coefficient itoalberti FLUENT 0 July 9, 2015 15:33
Ansys CFX Post Ckern CFX 2 June 30, 2014 09:34
ANSYS CFX POST State file Mechstud CFX 1 June 22, 2007 15:59

All times are GMT -4. The time now is 05:36.