Search found 83 matches

by Andy.Clifton
Thu Mar 10, 2016 12:29 pm
Forum: NWTC Wind Data
Topic: Formula to calculate CV2
Replies: 3
Views: 6681

Re: Formula to calculate CV2

The code for the structure function is in SubDissipationRateStructureFunction.m . This function is called from [url =https://github.com/NREL/TITANIC/blob/master/firstlook/FirstLook.m] FirstLook[/url] as follows: [epsilon_SF,lags,cv2,cv2m,DVV,cT2,cT2m,DTT] = ... SubDissipationRateStructureFunction(So...
by Andy.Clifton
Fri Feb 19, 2016 7:56 pm
Forum: NWTC Wind Data
Topic: Formula to calculate CV2
Replies: 3
Views: 6681

Re: Formula to calculate CV2

Hi Rabah,

if you look at items 2 and 3 on https://nwtc.nrel.gov/MetDataPublications, you should find what you are looking for. If you want to see the code, this is available through https://github.com/NREL/TITANIC.

Good luck,

Andy
by Andy.Clifton
Mon Jan 04, 2016 7:34 am
Forum: NWTC Wind Data
Topic: Offshore Wind Data
Replies: 11
Views: 7488

Re: Offshore Wind Data

Dear Ashenafi, The answer to this question really depends on what you want to do. This link to the paper that Jason provided is probably the best if you want to do turbine simulations. But, if you want real data, there are some data sets available for offshore winds at turbine hub heights (80-100 m)...
by Andy.Clifton
Thu Nov 19, 2015 10:11 am
Forum: NWTC Wind Data
Topic: M5 3-m aspirator replaced
Replies: 0
Views: 8222

M5 3-m aspirator replaced

The 3-m aspirator on M5 has been replaced (19 November 2015, 10:00 AM local time). The aspirator moves air through /past the 3-m temperature sensors. A microswitch is activated by a flap that moves in the airflow. This tells us that the aspirator is actually working. A signal is stored in the DAS an...
by Andy.Clifton
Thu Oct 22, 2015 6:32 pm
Forum: NWTC Wind Data
Topic: M4 Out of Service for winter 2015-2016
Replies: 0
Views: 8215

M4 Out of Service for winter 2015-2016

M4, the 135-m tower in the SE corner of the NWTC, will be out of service for the winter 2015-2016. M5 (the other 135-m tower) and M2 (80 m) will remain in operation. Data from M4 from 2012 -2015 are still available online at https://nwtc.nrel.gov/135mdata . Historic data from M5 and M2 can also be f...
by Andy.Clifton
Thu Jul 23, 2015 12:36 pm
Forum: NWTC Wind Data
Topic: Applying calibrations to data: please use new data files
Replies: 0
Views: 6646

Applying calibrations to data: please use new data files

We've found out that some of the data from approximately July 2014 - July 2015 may have been collected using the wrong instrument calibrations on many of the analog instruments. This affects the cups, vanes, temperature and humidity sensors, and barometric pressure sensors on both towers. This does ...
by Andy.Clifton
Thu Jul 23, 2015 12:31 pm
Forum: NWTC Wind Data
Topic: Data Version 1.41
Replies: 0
Views: 6088

Data Version 1.41

I have updated the met tower data processing software to version 1.41. What's new in version 1.41? - the software is designed to enable post processing to change instrument calibrations Data have not changed. There have been no other modifications made to the code. You should start to see this in da...
by Andy.Clifton
Thu Jun 25, 2015 10:04 am
Forum: NWTC Wind Data
Topic: M5 Maintenance Log
Replies: 11
Views: 11759

Re: M5 Maintenance Log

June 8, 2015: Annual Maintenance

M5 systems will be down for annual maintenance for 1-2 weeks from June 8, 2015. During this time we will be swapping in new / recalibrate instrumentation and updating the DAS computer.
by Andy.Clifton
Tue Feb 24, 2015 7:32 pm
Forum: NWTC Wind Data
Topic: M4 Maintenance Log
Replies: 8
Views: 8835

Re: M4 Maintenance Log

The new M4 DAS went live on February 21 and we have completed in-house testing. The new DAS has the same features as the DAS on M5: ⋅ Raw data are written using an XML-based format, called labview TDMS. we do all the conversion for you, so you will see no change to the raw data on the web ...
by Andy.Clifton
Mon Jan 19, 2015 6:23 pm
Forum: NWTC Wind Data
Topic: Data Version 1.40
Replies: 0
Views: 5490

Data Version 1.40

I have updated the met tower data processing software to version 1.40. What's new in version 1.40? - the software is designed to cope with different file formats, including Labview TDMS, which we have just started using on M5. - the software is designed to cope with DAS that have multiple sampling r...
by Andy.Clifton
Mon Jan 19, 2015 6:19 pm
Forum: NWTC Wind Data
Topic: M4 Maintenance Log
Replies: 8
Views: 8835

Re: M4 Maintenance Log

Data processing routines have been updated to work with the new DAS on the M5 tower, so you will see M4 data with version 1.4 in the next few days. The M4 tower is still operating on the previous DAS, however.
by Andy.Clifton
Mon Jan 19, 2015 1:48 pm
Forum: NWTC Wind Data
Topic: M5 Maintenance Log
Replies: 11
Views: 11759

Re: M5 Maintenance Log

The new M5 DAS went live on January 1 and we have completed in-house testing. The new DAS has the following features: ⋅ Raw data are written using an XML-based format, called labview TDMS. we do all the conversion for you, so you will see no change to the raw data on the web server. ⋅...
by Andy.Clifton
Mon Dec 15, 2014 5:05 pm
Forum: NWTC Wind Data
Topic: M5 Maintenance Log
Replies: 11
Views: 11759

Re: M5 Maintenance Log

The M5 DAS was taken offline on November 13 to trial new DAS software which is expected to substantially improve reliability. We expect to have the new DAS running by early January 2015. The raw data format may change at this time, which will necessitate some rewriting of the data handling code. Thi...
by Andy.Clifton
Mon Dec 15, 2014 5:02 pm
Forum: NWTC Wind Data
Topic: M4 Maintenance Log
Replies: 8
Views: 8835

Re: M4 Maintenance Log

The M4 DAS failed on December 5 and was restarted on December 14. Approximately 8 days of data have been lost.
by Andy.Clifton
Fri Sep 12, 2014 5:10 pm
Forum: NWTC Wind Data
Topic: First snow of 2014/2015 winter
Replies: 0
Views: 5453

First snow of 2014/2015 winter

The title says it all. We had the first snow of the winter today, between about 1:00 UTC on 9/12. it's carried on intermittently all day. Effects include frozen cups, loss of signal on the sonics, and high humidity at all levels. Please check the flags for risk of icing or risk of fog if you are ana...

Go to advanced search