# Wake Behind Oscillating Airfoil_No Vortices

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

February 11, 2018, 14:10
Wake Behind Oscillating Airfoil_No Vortices
#1
New Member

frantsesko
Join Date: Oct 2017
Posts: 3
Rep Power: 7
Hallo my friends ,

I am trying to simulate, in Fluent 15.0 , an oscillating airfoil, in 2D, with the following characteristics :

1)NACA 64418
2)heaving amplitude =0.05 m
3)pitching amplitude =4 degrees
4)air inlet speed =26.4 m/s (Re=0.85 * 10^6)
5)chord =0.5
6)pivot point =chord/3 (from leading edge)
7)heaving eq. of motion :h=0.05*sin(2*pi*t)
8)pitching eq. : a=1+4*sin(2*pi*t)
9)time step = 0.001 s

The turbulence model i am using is the Realizable k-e .
In order to simulate the pitch and heave motion i use sliding mesh, which is attached to the airfoil , which moves also vertically (with magnitude of motion 0.05 m) .

Mesh characteristics :
1)y+=1
2)1878 elements on airfoil
3)inflation with 30 layers and growth rate 1.2
4)170.000 elements in total

The problem i am having is that in the velocity curl contours i cant see any vortices . (see attachment)
Should there be any at this amplitudes of oscillating motion and velocity ?

In the picture you can see the velocity curl field every 0.25T of the motion .

Thank you very much in advance .
Attached Images
 velocity_curl_airfoil_shot.png (61.0 KB, 10 views)

 February 14, 2018, 08:16 #2 New Member   frantsesko Join Date: Oct 2017 Posts: 3 Rep Power: 7 Any Help ?

 Tags airfoil 2d, fluent, oscillating airfoil, vortices, wake