Angle of attack

tyw7 · February 18, 2019, 13:25

I was trying to simulate an angle of attack, but the flow line looks dodgy.

I use the cartesian velocity components.

I am assuming u v w corresponds to the XYZ components?

ghorrocks · February 18, 2019, 17:23

I have no idea what that image is showing. Please explain what the image is showing.

tyw7 · February 18, 2019, 17:25

Flow of air over the wing. I am trying to do an angle of attack of 10 deg. So I put in a x component and a z component. And it threw out something weird as shown.

What's the correct way to do it?

ghorrocks · February 18, 2019, 17:29

What does your domain look like? Where are the boundary conditions?

tyw7 · February 18, 2019, 17:34

Domain is a box around a "wing". Inlet in front, outlet at the back.

Wing is free slip, wall is symmetry. Inlet is inlet, outlet is outlet.

AOA10
x
y 19.8717
z -3.50393

y is the normal, x is tangential, z is upward.

ghorrocks · February 18, 2019, 17:37

The problem appears to be your top and bottom boundaries are too close to the airfoil. You need to make it bigger.

tyw7 · February 18, 2019, 17:39

I thought so too. Is there a way to simulate it as if it's flying through the air? My instructor says setting it as symmetric is better than free slip.

In theory, should my setup work (assuming larger box) to simulate an AOA?

Also, what should the streamline look like if I have a bigger box?

ghorrocks · February 18, 2019, 19:33

You should look in the literature to see what other people do. That can be both the published articles and a google search. That is always the starting point for a new project.

February 18, 2019, 17:23		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	I have no idea what that image is showing. Please explain what the image is showing. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

February 18, 2019, 17:29		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	What does your domain look like? Where are the boundary conditions? __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

February 18, 2019, 17:37		#6
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	The problem appears to be your top and bottom boundaries are too close to the airfoil. You need to make it bigger. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

February 18, 2019, 19:33		#8
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	You should look in the literature to see what other people do. That can be both the published articles and a google search. That is always the starting point for a new project. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
[Netgen] Import netgen mesh to OpenFOAM	hsieh	OpenFOAM Meshing & Mesh Conversion	32	September 13, 2011 06:50
introducing angle of attack on ICEMCFD HEXA	icem beginner	CFX	2	December 24, 2008 12:00
introducing angle of attack on ICEMCFD HEXA	icem beginner	Main CFD Forum	3	December 17, 2008 06:05
introducing angle of attack on ICEMCFD HEXA	icem beginner	FLUENT	2	December 6, 2008 16:34
angle of attack	kiran	FLUENT	0	September 10, 2004 09:18

February 18, 2019, 17:25		#3
tyw7 Member Thu Win Join Date: Apr 2017 Posts: 70 Rep Power: 9	Flow of air over the wing. I am trying to do an angle of attack of 10 deg. So I put in a x component and a z component. And it threw out something weird as shown. What's the correct way to do it?

February 18, 2019, 17:34		#5
tyw7 Member Thu Win Join Date: Apr 2017 Posts: 70 Rep Power: 9	Domain is a box around a "wing". Inlet in front, outlet at the back. Wing is free slip, wall is symmetry. Inlet is inlet, outlet is outlet. AOA10 x y 19.8717 z -3.50393 y is the normal, x is tangential, z is upward.

February 18, 2019, 17:39		#7
tyw7 Member Thu Win Join Date: Apr 2017 Posts: 70 Rep Power: 9	I thought so too. Is there a way to simulate it as if it's flying through the air? My instructor says setting it as symmetric is better than free slip. In theory, should my setup work (assuming larger box) to simulate an AOA? Also, what should the streamline look like if I have a bigger box?