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

y+ viscous sublayer query

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   April 5, 2021, 07:11
Default y+ viscous sublayer query
  #1
New Member
 
Jowan S
Join Date: Feb 2021
Posts: 3
Rep Power: 5
Jowan is on a distinguished road
Dear CFD users

As part of my project, I am looking at the lift and drag coefficients for an aerofoil by doing 2D CFD simulations in Ansys Fluent.

I have been advised that my model should have a y+<11 to be in the viscous sublayer, however I was unable to get the y+ of my model less than 180.

Am I correct in thinking that this is also acceptable as this is outside the buffer zone and so is approximated sufficiently by the wall functions?

If so, what is the advantage of the y+ being in the viscous sublayer rather than in the turbulent zone?



I am quite new to CFD and a novice in terms of y+ but would like to touch on it briefly in my reports so would appreciate it if some one was kind enough to answer these questions.

Thanks a lot in advance!
Jowan is offline   Reply With Quote

Old   April 5, 2021, 18:48
Default
  #2
Senior Member
 
Lorenzo Galieti
Join Date: Mar 2018
Posts: 375
Rep Power: 12
LoGaL is on a distinguished road
It may work, sometimes the wall function is accurate, sometimes not, who knows... It is definitely better to solve the boundary layer rather than calculating it with a wall function, especially for airfoils. So yes, aim for y+ = 1, follow what your supervisor told you
LoGaL is offline   Reply With Quote

Old   April 5, 2021, 19:38
Default
  #3
Senior Member
 
Lorenzo Galieti
Join Date: Mar 2018
Posts: 375
Rep Power: 12
LoGaL is on a distinguished road
Double post error
LoGaL is offline   Reply With Quote

Reply

Tags
aerofoil, ansys fluent, ansys workbench, y plus ranges, y plus selection


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
Y+ for viscous sublayer 2D airfoil frossi CFX 1 October 27, 2019 18:12
Residuals and forces spiraling out of control before failing edomalley1 OpenFOAM Running, Solving & CFD 3 September 7, 2018 11:42
Viscous Sublayer thickness sihaqqi OpenFOAM 2 January 1, 2015 18:16
viscous sublayer in turbuelt flows student Main CFD Forum 0 June 22, 2007 06:05
High aspect ratio in viscous sublayer? Marius Main CFD Forum 0 December 22, 2005 09:15


All times are GMT -4. The time now is 14:10.