Discussion Groups

## Simulation CFD

Product Support
Posts: 290
Registered: ‎08-31-2011

# Re: NACA AEROFOIL 2415 lift coefficient calculation is not accurate !!!!!!!

When dealing with 2D, or a section of a wing, you can look at Section Lift Coefficient

Here the equation is  (2*L) / rho * V^2 * c

Since the chord length is 1 this copmutes out to a Lift coefficient of 0.21

As you noticed in the meshing dialog, there are a number of edges that make up the airfoil so you will have to select all of the edges not just the 2 edges that are easily selected.

You are correct, Mesh Adapation is not supported in 2D, however Mesh Refinement Regions are as the file I sent you contained a mesh refinement region assigned. I outlined this when i was describing the mesh strategy.

If you look at the Wall Calculator, you will see that we give information as to the Center of Force, however you will want to select all edges before trying to use this value to get an accurate representation of the pressure distribution.

Apolo

Active Member
Posts: 8
Registered: ‎10-15-2012

# Re: NACA AEROFOIL 2415 lift coefficient calculation is not accurate !!!!!!!

10-19-2012 06:03 AM in reply to: apolo.vanderberg

i am done in caculating for lift coefficient..

next i am going to do 3d simulation for horizontal axis wind turbine..

my questions are :

1 : does 3d simulation also already including WEIGHT in calculation (for example, when i am going to use wood and steel for torque calculation / Lift force, is there any different between wood and steel's result assuming that both surface roughness are zero) and for thermal analysis does 3d simulation is there any different for different material assuming one and another materials have different heat coefficient)

2 : is it possible to know how much rotational speed that a wind turbine can produce by given air's speed ?

i am going to validate my result after designing wind turbine by matching the rotational speed produced by simulation and designed rotational speed

Product Support
Posts: 290
Registered: ‎08-31-2011

# Re: NACA AEROFOIL 2415 lift coefficient calculation is not accurate !!!!!!!

To keep things clean for future users I would suggest you start a new thread for new questions.

1. In short-for steadystate, weight is not acting on the model it is just the flow field specified

2. Yes, Simulation CFD can predict RPM of free spinngin devices, this is done with a Rotating Region - please see the Help Section for how to set these up and Best Practices as well as the Example pump model that will get you experience with this before trying to do this on a full wind turbine.