Search found 16 matches
- Tue Mar 27, 2018 8:41 am
- Forum: Computer-Aided Engineering Software Tools
- Topic: MLife Fatigue DEL Calculation
- Replies: 31
- Views: 15777
Re: MLife Fatigue DEL Calculation
Hello Simon, Unfortunately, we do not have the resources to supported pre-compiled versions of MLife at this time. The good news is that you can still use MLife! You simply need to create your own version of the Weibull cumulative distribution function, wblcdf() function. https://www.mathworks.com/h...
- Mon Aug 14, 2017 11:24 am
- Forum: Computer-Aided Engineering Software Tools
- Topic: Announcing MExtremes
- Replies: 24
- Views: 6648
Re: Announcing MExtremes
The tilde operator was introduced with MATLAB Version 7.9 (R2009b). https://www.mathworks.com/help/matlab/matlab_prog/ignore-function-outputs.html You will need to place dummy variables where ever you see ~ in a function output list for this code to work with your version of matlab. There may be add...
- Tue Jun 20, 2017 7:56 am
- Forum: Computer-Aided Engineering Software Tools
- Topic: MLife Fatigue DEL Calculation
- Replies: 31
- Views: 15777
Re: MLife Fatigue DEL Calculation
For item (1), you need to modify Test02.mlif to use the StrNames functionality. It should now run without any errors. true StrNames Use channel names following a "$" instead of numbers when specifying channels in this input file. 2) You can access the binned rainflow counts via the data st...
- Tue May 09, 2017 7:11 am
- Forum: Computer-Aided Engineering Software Tools
- Topic: Problems running MLife without MatLab
- Replies: 3
- Views: 2151
Re: Problems running MLife without MatLab
Dear Tohid, Unfortunately I cannot reproduce your errors. I've 1) downloaded the MLife archive with the precompiled binaries ( https://nwtc.nrel.gov/system/files/MLife_v1.00.00f-gjh_1.exe ), 2) extracted the archive to a local folder. 3) Copied the contents of the Data folder into the CertTest folde...
- Fri Jan 20, 2017 1:44 pm
- Forum: Computer-Aided Engineering Software Tools
- Topic: Problems running MCrunch CertTest
- Replies: 6
- Views: 4287
Re: Problems running MCrunch CertTest
Simon,
I have not run MCrunch with a version of MatLab newer than 2014a. Can you paste the error message you are receiving with your version of MatLab?
Thanks,
Greg
I have not run MCrunch with a version of MatLab newer than 2014a. Can you paste the error message you are receiving with your version of MatLab?
Thanks,
Greg
- Thu Aug 25, 2016 9:33 am
- Forum: Computer-Aided Engineering Software Tools
- Topic: Water ballasting & buoyancy loads
- Replies: 6
- Views: 2896
Re: Water ballasting & buoyancy loads
Romain, Thank you for reporting this issue. I have verified the problem in the current version of HydroDyn (v2.05). This bug was created when we added user supplied wave kinematics and with our wave stretching implementation. Some additional code is needed in the WriteSummaryFile() subroutine of Mor...
- Wed May 11, 2016 2:23 pm
- Forum: Computer-Aided Engineering Software Tools
- Topic: fatigue calculation
- Replies: 15
- Views: 5444
Re: fatigue calculation
Dear Srinivasa,
wblcdf() is a MatLab function found in the statistics toolbox. You will need to have a license for this toolbox, or replace the wblcdf() call with your own code to calculate the weibull distribution.
Greg
wblcdf() is a MatLab function found in the statistics toolbox. You will need to have a license for this toolbox, or replace the wblcdf() call with your own code to calculate the weibull distribution.
Greg
- Mon May 18, 2015 9:20 am
- Forum: Computer-Aided Engineering Software Tools
- Topic: MLife CertTest
- Replies: 1
- Views: 2807
Re: MLife CertTest
Hello Scott, Thank you for pointing out the discrepancy between the User's Guide and the archive. At some point, I changed the name of the script to: mlife_regression_test.m This script is identical to the original mlife_certification_tests.m script. I'll be sure to update the documentation for any ...
- Mon Sep 22, 2014 8:51 pm
- Forum: Computer-Aided Engineering Software Tools
- Topic: damage equivalent load
- Replies: 3
- Views: 3850
Re: damage equivalent load
Dear Mehdi, You might want to look at the certification tests under the CertTest folder of the MLife distribution. Test02.mlif and Test05.mlif both generate short-term DELs. If you examine the MLife_User.pdf, located in the documentation folder, you will be able to interpret the various parameters. ...
- Wed Jul 09, 2014 2:11 pm
- Forum: Computer-Aided Engineering Software Tools
- Topic: Output hydrodynamic forces
- Replies: 5
- Views: 4275
Re: Output hydrodynamic forces
Dear Shining.Zhang, In terms of your first item, the HydroDyn manual, https://wind.nrel.gov/designcodes/simulators/hydrodyn/HydroDyn_Manual.pdf , Appendix C has a complete list of available HydroDyn outputs. There are channels for all the various load contributions due to potential flow theory as we...
- Mon Apr 08, 2013 10:32 am
- Forum: Computer-Aided Engineering Software Tools
- Topic: MLife Fatigue DEL Calculation
- Replies: 31
- Views: 15777
Re: MLife Fatigue DEL Calculation
Yulin, Your questions about the specification of both L_MF and L_Ult is a common one. Unfortunately, there is no general answer that I can give you. In my opinion, the answer depends on the nature of your analysis/study, and the available information you have about your turbine design. For generaliz...
- Mon Apr 08, 2013 10:07 am
- Forum: Computer-Aided Engineering Software Tools
- Topic: Mlife
- Replies: 1
- Views: 1572
Re: Mlife
Florian, as stated in the MLife User's Guide on page on page 6, "If you wish, DELs can be outputted as peak-to-peak ranges (DEL_AsRange = true) or as one-sided amplitudes (DEL_AsRange = false)." The rainflow counts themselves are tracked based on the number of full cycles (valley-to-peak-t...
- Mon Oct 22, 2012 1:05 pm
- Forum: News and Announcements
- Topic: Software Releases
- Replies: 17
- Views: 106168
Updated version of MLife software (v1.00.00f-gjh)
We are happy to announce an updated alpha-version release of MLife (v1.00.00f-gjh), a MatLab-based tool that can efficiently process statistical and fatigue-related output needed for wind turbine certification. MLife's calculations follow the method required by the IEC in their 61400-1 Edition 3, An...
- Tue Dec 13, 2011 2:03 pm
- Forum: Computer-Aided Engineering Software Tools
- Topic: New NWTC/NREL Fatigue-life estimation tool
- Replies: 3
- Views: 4648
Re: New NWTC/NREL Fatigue-life estimation tool
We have discovered a bug in the v1.00.00b-gjh release related to the calculation of wind speed bin probabilities. Currently the scale factor for the Weibull distribution is set to 2*Vave / sqrt(pi), but this should only be the case when a shape factor of 2 is used (in other words a Rayleigh distribu...
- Mon Dec 05, 2011 1:45 pm
- Forum: Computer-Aided Engineering Software Tools
- Topic: New NWTC/NREL Fatigue-life estimation tool
- Replies: 3
- Views: 4648
New NWTC/NREL Fatigue-life estimation tool
Call for Alpha Testers (NWTC/NREL Fatigue-life estimation Tool) We are happy to announce an alpha-version release of MLife, a MatLab-based tool that can efficiently process statistical and fatigue-related output needed for wind turbine certification. MLife's calculations follow the method required b...