Forum

Please or Register to create posts and topics.

Question about Char BEM for standing still rotor

Hello Dr!

First of all, thank you all for your work in this wonderful software.

My question is, and maybe it is out of the intended scope of the software:

Can I obtain the approximate torque at the hub running the Char BEM simulation for the NREL_5MW with wind speeds up to 28 m/s, varying the pitch from 0 to 90 and fixing the rotational speed to 0.01?

What I am trying to simulate is the rotor in stand still position (QBlade doesn’t allow to fix the rotational speed at 0)

Please check attached file.

Just wondering if what I am trying to do makes any sense to you.

Thank you!!

 

Uploaded files:
  • You need to login to have access to uploads.

Hi Alex,

yes, what you are trying to do is very much possible.

The value of 0.01 rpm is a very good approximation of a standing rotor (it needs 100min for one full revolution).

In the CharBEM module you can change the main variable and the parameter variable for each graph to get the results that I have attached.

What you see on the left is the torque per windspeed where each curve represents a pitch angle and on the right you see the torque over the pitch angle where each curve represents a windspeed. You can see on the right that around 90° pitch the torque is zero for all windspeeds…

BR,

David

Uploaded files:
  • You need to login to have access to uploads.

Hello David!

Thank you so much for your review, it is very much appreciated.

What I have noticed is that when you pass the 88 degree pitch the  values change to negatives, but this is maybe related to the rotor geometry.

Looks like it is starting to spin in the other direction (I would assume, maybe I am wrong) but anyways, your response helps me a lot actually.

So, thank you again!!