CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > COMSOL

Airfoil CFD in COMSOL / issues

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

LinkBack Thread Tools Search this Thread Display Modes
Old   June 17, 2015, 05:33
Default Airfoil CFD in COMSOL / issues
New Member
xenofon kalogeropoulos
Join Date: May 2014
Posts: 1
Rep Power: 0
xenofon9 is on a distinguished road
Dear all,

I am in the process of doing a study of double staggered airfoils in Comsol 4.4. Before starting to analyze double airfoils I though it would be good to validate a single airfoil model against XFoil and experimental data. My goal is to run CL/CD predictions in a reasonable AoA range, say 0-10 degrees. Let me walk you through my setup of this study:

- Re = 1x10e6
- Airfoil: SG6043, with 1m chord length
- Fluid Domain: C-domain, radius of 5 chords and downstream length of 10 chords
- Turbulence model: SST
- Boundary layer setup: Yplus ~1 with 20 layers and first layer height calculated as 2.3e-5 m, stretching = 1.3 (see attached images)
- Inlet turbulence variables: Intensity = 0.1%, Length scale = 0.001m

As of yesterday, my best results so far (Comparing to XFoil results are):
Lift: Maximum error: 11%, this is reasonable but should be reduced a bit more.
Drag: Maximum error: 27% (over-prediction), I know drag is extremely difficult to predict accurately due to various effects including possible laminar-to-turbulent transition inside the BL, but the error should be decreased further for my analysis to become reliable at this stage.

I think the most important factor here would be to fix my mesh to be as solid as possible to capture fully the viscous effects that dictate drag. So your advice regarding my mesh (or any other advice indeed) would be extremely helpful.

My first thoughts is that something is not quite right with the leading edge (see images) because the BL mesh is very distorted there. After the solver has done its job, the wall resolution plot shows very high values there, so my effective Yplus at the leading edge's area is much higher than the desired value of 1.

Thanks for your time and effort guys, your feedback will be greatly appreciated!

Best Regards

xenofon9 is offline   Reply With Quote


aerodynamics, aerofoil, airfoil, cfd, wind turbine

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
SU2 AOA optimization SU2 9 March 7, 2022 17:17
flow over an airfoil 3d ( Geometry on icem cfd ) dfmona Main CFD Forum 0 April 14, 2010 00:32
Transonic Aeroelastic CFD code for an Airfoil Nicholas Amuyedo Main CFD Forum 8 August 8, 2007 09:25
CFD for fans & blower housings David Carroll Main CFD Forum 8 August 24, 2000 18:25
CFD Technology Issues CFDsurvey Main CFD Forum 2 July 7, 1998 01:56

All times are GMT -4. The time now is 23:42.