CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > General Forums > Main CFD Forum

Y+ confusion

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   November 17, 2023, 23:12
Default Y+ confusion
  #1
New Member
 
Gabriel
Join Date: Nov 2023
Posts: 4
Rep Power: 2
Gabreeal is on a distinguished road
Dear Sir/Madam,

I had been simulating flow over OneraM6 wing at transonic regime. The y+ value for komega SST is preferably 1, for K epsilon should be 30<y+<300.

Currently I have used Spalart Allmaras because of doing validation. Now I have heard that Spalart Allmaras is insensitive to y+ value, so the mesh layer height will get automatically adjusted (correct me if I am wrong).
The boundary layer thickness is nearly 0.0170, so have put this distance in the mesh size of 1st cell.

This again to be taken into account, for viscous sublayer y+ is below 5 and more than 30 for logarithmic. (No idea is range of 300 can be considered here or not)

I ran the simulation, the plots for Cp, M, velocity are understandable. Now If I plot the y+ over surface (from additional data file quantities in Ansys CFD post), there is wide variation of y+ over wing surface. Legend shows from 0.2 to 500. I am attaching a picture below. Kindly explain how to interpret this plot and why is y+ value more than 300, around 500 for Spalart Allmaras model. If this contour is incorrect, then why other contours of pressure and velocity parameters are near about matching the values of validation data?

Regards
Gabreeal
Attached Images
File Type: jpg Yplus-min.jpg (53.5 KB, 7 views)
Gabreeal is offline   Reply With Quote

Reply


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
Confusion Regarding Inlet Boundary Condition for Detonation Simulation niyas Main CFD Forum 3 March 9, 2023 02:40
Confusion in calculation of u', the velocity flucation ckpark Main CFD Forum 13 March 21, 2022 08:40
some confusion about "bool" warnerchang OpenFOAM Programming & Development 11 April 17, 2021 11:30
Confusion choosing between static / transient simulations TharunSK CFX 1 March 15, 2019 18:53
some confusion about the radiation model of Floefd jason kid FloEFD, FloWorks & FloTHERM 4 March 3, 2016 08:13


All times are GMT -4. The time now is 04:37.