# How to apply right hand rule on 2D face to decide the Face Area Normal Direction?

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September 16, 2015, 01:59
How to apply right hand rule on 2D face to decide the Face Area Normal Direction?
#1
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I am looking at the manual section "3.2.4.2.*Face Area Vector (F_AREA)."

There is a figure as attached, which said:
ANSYS FLUENT*determines the direction of the face area normals for interior faces by applying the right hand rule to the nodes on a face, in order of increasing node number.

I don't know how to apply the right hand rule to get the normal vector in 2D and 3D.
Could someone help?
Thank you!
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September 16, 2015, 03:58
#2
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Quote:
 Originally Posted by SJSW I am looking at the manual section "3.2.4.2.*Face Area Vector (F_AREA)." There is a figure as attached, which said: ANSYS FLUENT*determines the direction of the face area normals for interior faces by applying the right hand rule to the nodes on a face, in order of increasing node number. I don't know how to apply the right hand rule to get the normal vector in 2D and 3D. Could someone help? Thank you!
Your elbow is at node 0, your fingers is at node 1, you bend 4 of your fingers in the direction of screen normal then your thumb is desired normal.

July 21, 2023, 03:40
#3
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Feiwei Dou
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Quote:
 Originally Posted by Antanas Your elbow is at node 0, your fingers is at node 1, you bend 4 of your fingers in the direction of screen normal then your thumb is desired normal.
Hello

I want to know how to decide 0 and 1 in other cases. It seems that if we decided the 0 and 1, then we will obtain the Normal Direction.

Thanks!

 July 23, 2023, 00:12 #4 Senior Member   Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,496 Rep Power: 64 0,4,58 etc are the node numbers which are decided by the orders that the coordinates are listed in the mesh. When the nodes are created, they are assigned numbers.