Low Lift Coefficient in ground simulations of 2D Airfoil (URGENT)

Umayr91 · April 7, 2021, 05:56

Hi there, I am university student and in major need of help. I'm running 2d simulations on a 30P30N Airfoil which I've simulated in free flight and now I have run in ground simulations with a h/c of 1. My lift values for ground are lower than my free flight simulations for whatever reason and I cannot figure it out despite many changes. Can anyone assist? These are my results:

FREE FLIGHT
Alfa CL - CD - CM
0 - 2.1414 0.050072 0.22063
4 - 2.6703 0.050454 0.09339
8 - 3.1056 0.064482 -0.03591
12 - 3.3856 0.093385 -0.16095

IN GROUND
Alfa CL - CD - CM
0 - 2.0035 0.044599 0.20268
4 - 2.3253 0.036799 0.07713
8 - 2.6291 0.052558 -0.04001
12 - 2.8262 0.079061 -0.14552

I've attached some pictures of basic settings/reference values:
Screenshot 2021-04-07 at 10.52.49.jpg

Screenshot 2021-04-07 at 10.53.22.jpg

Screenshot 2021-04-07 at 10.53.50.jpg

I would really appreciate some urgent help as my degree depends on it. Thank you so much for your time.

Umayr91 · April 7, 2021, 06:02

A couple more settings

Screenshot 2021-04-07 at 11.00.40.jpg

Screenshot 2021-04-07 at 11.01.14.png

MekTek · April 25, 2021, 04:51

How does your mesh settings look like?

April 7, 2021, 05:56	Low Lift Coefficient in ground simulations of 2D Airfoil (URGENT)	#1
Umayr91 New Member Umayr Join Date: Apr 2021 Posts: 2 Rep Power: 0	Hi there, I am university student and in major need of help. I'm running 2d simulations on a 30P30N Airfoil which I've simulated in free flight and now I have run in ground simulations with a h/c of 1. My lift values for ground are lower than my free flight simulations for whatever reason and I cannot figure it out despite many changes. Can anyone assist? These are my results: FREE FLIGHT Alfa CL - CD - CM 0 - 2.1414 0.050072 0.22063 4 - 2.6703 0.050454 0.09339 8 - 3.1056 0.064482 -0.03591 12 - 3.3856 0.093385 -0.16095 IN GROUND Alfa CL - CD - CM 0 - 2.0035 0.044599 0.20268 4 - 2.3253 0.036799 0.07713 8 - 2.6291 0.052558 -0.04001 12 - 2.8262 0.079061 -0.14552 I've attached some pictures of basic settings/reference values: Screenshot 2021-04-07 at 10.52.49.jpg Screenshot 2021-04-07 at 10.53.22.jpg Screenshot 2021-04-07 at 10.53.50.jpg I would really appreciate some urgent help as my degree depends on it. Thank you so much for your time.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Calculation of lift and drag coefficients on airfoil	CoolHersheys	OpenFOAM Post-Processing	5	September 27, 2021 06:04
Lift coefficient with my 2.5D airfoil model never matches the experimental data.	ktgfeel	FLUENT	1	December 15, 2014 12:58
Lift coefficient too low	antonio_ing	OpenFOAM Running, Solving & CFD	7	April 19, 2014 03:03
airfoil lift and drag coefficient	amir_14	FLUENT	5	January 1, 2013 08:30
Automotive test case	vinz	OpenFOAM Running, Solving & CFD	98	October 27, 2008 08:43

April 7, 2021, 06:02		#2
Umayr91 New Member Umayr Join Date: Apr 2021 Posts: 2 Rep Power: 0	A couple more settings Screenshot 2021-04-07 at 11.00.40.jpg Screenshot 2021-04-07 at 11.01.14.png

April 25, 2021, 04:51		#3
MekTek New Member Venkat Join Date: Apr 2019 Location: Bengaluru Posts: 7 Rep Power: 6	How does your mesh settings look like?