AeroDyn: RElm produces ill-conditioned DR

Provide feedback, request enhancements, and get help with wind-turbine computer-aided engineering tools.

Moderators: Bonnie.Jonkman, Jason.Jonkman

Timo.Strotbaum
Posts: 6
Joined: Mon Jun 04, 2018 10:18 am
Organization: RWTH Aachen
Location: Germany

AeroDyn: RElm produces ill-conditioned DR

Postby Timo.Strotbaum » Thu Apr 04, 2019 9:50 am

Hi,

I´m trying to run a multi-body-simulation, which is using AeroDyn V13, but i can´t start it because of an error with my AeroDyn input file.
First of all, i found two different versions of input files, one defining the blade elements by RElm and DR, while the other one used the terms RNodes and DRNodes.
Are there any differences between these two Versions?
When using the following Numbers, i get an error massage saying "RElm(2) produces ill-conditioned DR(:)". I already read the FAQ about Nodes (https://nwtc.nrel.gov/faq#Nodes) and the AeroDyn Documentation, but i can´t figure out what´s wrong with these Numbers. the Hub-Radius of my model is 1.565m.

Code: Select all

RElm   DR
2.565   2
3.865   0.6
5.165   2
6.365   0.4
7.665   2.2
...      ...


thanks in advance!

Jason.Jonkman
Posts: 4105
Joined: Thu Nov 03, 2005 4:38 pm
Location: Boulder, CO
Contact:

Re: AeroDyn: RElm produces ill-conditioned DR

Postby Jason.Jonkman » Thu Apr 04, 2019 12:15 pm

Dear Timo,

If I recall correctly for these old versions of FAST and AeroDyn, the FAST documentation used RNodes and DRNodes and the AeroDyn documentation used RElm and. Regardless, they are equivalent.

If you hub radius is really set to 1.565 m, I don't see any problem with your RElm or DR data for these first five nodes. Could the problem be in one or more of the more outboard nodes?

Best regards,
Jason Jonkman, Ph.D.
Senior Engineer | National Wind Technology Center (NWTC)

National Renewable Energy Laboratory (NREL)
15013 Denver West Parkway | Golden, CO 80401
+1 (303) 384 – 7026 | Fax: +1 (303) 384 – 6901
nwtc.nrel.gov

Timo.Strotbaum
Posts: 6
Joined: Mon Jun 04, 2018 10:18 am
Organization: RWTH Aachen
Location: Germany

Re: AeroDyn: RElm produces ill-conditioned DR

Postby Timo.Strotbaum » Fri Apr 05, 2019 10:41 am

Dear Mr. Jonkman,

thank you for your quick answer. The Numbers of RElm and DR were indeed correct, i found the problem in the multi-body-simulation program, which is using AeroDyn.

Best regards,

Timo


Return to “Computer-Aided Engineering Software Tools”

Who is online

Users browsing this forum: No registered users and 1 guest