Dear @Nitin.Sivakumar,

How many *.out* files are you using? Do all of them have the same number of time steps and same number of output channels? Have you tried running with just one of your *.out* files (`NumDLCfiles`

= 1)?

Best regards,

Dear @Nitin.Sivakumar,

How many *.out* files are you using? Do all of them have the same number of time steps and same number of output channels? Have you tried running with just one of your *.out* files (`NumDLCfiles`

= 1)?

Best regards,

Dear sir,

I am interested in using 3 *.out* files however, I tried with 1 *.out* file also with âNumDLCfiles=1â. Yes all of them have the same number of time steps and output channels.

Thanks and Regards

Dear @Nitin.Sivakumar,

Does MExtremes run with `NumDLCfiles`

= 1 and one of our *.out* files? If not, what is the error?

Best regards,

Dear sir,

Yes, it is working with 1 *.out* file added. No errors are shown. I am attaching the screenshot of the Matlab command window for your reference.

Thanks and Regards

Dear @Nitin.Sivakumar,

Iâm not sure what the problem is. My understanding is that MExtremes runs fine running the original Test02 case with three files, but you when you use your three files it doesnât work. But switching to one of your files does work. What is you use two of your files or three files, but all files exactly the same as the case that does work?

Best regards,

Dear sir,

There has been a misunderstanding. From your last message, I could read âone of **our** .out filesâ , so the last result I showed was with the âDLC2.3_1.outâ which is one of your files (as you can see in the screen capture). I could never complete the simulation with either 1 or three of my *.out* files.

Best Regards

Dear sir,

I had modified one of my previous post and attach a google drive link because the .out file is a large file. I will attach again anyway.

Regards

https://drive.google.com/drive/folders/1_o45hVBBbQPOewVPCzPrsfmUBO0r7dBH?usp=sharing

Dear @Nitin.Sivakumar,

Can you also share your modified *.mext* file for the `NumDLCfiles`

= 1 case and and resulting error you are receiving?

Best regards,

Dear Jason sir,

I was mistaking the wind channel name to be same in both out files. But in the original one it was $WindVxi$ and in mine it was $Wind1VelX$. This was causing me errors. Now it worked. Thank you for your patience and sorry for not noticing.

Best Regards

1 Like

Dear sir,

I have one more doubt in a post you made regrding the selection of LUlt. In this segment of your post, I have attached below, do you mean I need to take the maximum value of desired channel in the extreme out file and multiply by the scaling factors of 1.25 to 20 and use those values for MLife simulation as L_Ult and observe the DEL value. But I could not understand what you meant by approaching asymptotical stability and how to observe that. Can you make it a bit clearer. Thanks in advance.

Best Regards

Ideally, LUlt would be based on a strength (e.g., FEA) analysis of the cross section of the component in question. If this is not availableâfor conceptual designs for exampleâwhat weâve done in the past is to see how the fatigue loads vary over a range of LUlt values. Weâve defined a range by taking the overall maximum value of the load in question (e.g., derived from MExtremes), and multiplying by scaling factors of 1.25, 2.5, 5, 10, and 20. The fatigue loads will asymptotically approach a fixed value for large values of LUlt.

Dear @Nitin.Sivakumar,

If you donât know the ultimate strength of a given cross section, but you need to know the LUlt value, what weâve done in the past is to use some multiple of the overall maximum value of the given load. The DEL will approach a fixed value for large values of LUlt.

Best regards,

Dear sir,

The maximum value of load means maximum value of desired channel of .out file (e.g. RootMyb) found from Mextreme . Am I correct.

Correct. More specifically, the maximum absolute value over all load cases.

Dear sir,

Thank you very much.

Best Regards

Dear sir,

I am interested in carrying out the DLC 1.2 test for observing the load reduction due to the turning ON of IPC on a turbine. I am having the turbine model in DNV bladed and my controller is also setup for the Bladed model. But I am not sure how to do the DLC 1.2 test in the Bladed. I gather from the posts in the forum that it possible with the NREL platform. Can you suggest me any method to carry out the test using the NREL platform.

Dear @Nitin.Sivakumar,

You should reach out to DNV for Bladed technical support.

By âNREL platformâ, do you mean OpenFAST?

Iâll just say that both OpenFAST and Bladed can simulate DLC 1.2 both with and without IPC enabled.

Best regards,

Dear sir,

I had gathered from discussions in the forum that MLIFE is suitable for DLC 1.2 calculations. I had tried using MLIFE and understood that Test 8 in MLIFE can take data from Matlab data matrices and process it to give the results. But I had a problem: MExtremes doesnât have the option to take data from external matrices but accepts only OpenFast .OUT files as input. So I am confused about how to calculate the LULT, to be used for the MLIFE calculations. I am not sure if you have understood my question.

Best Regards

Dear @Nitin.Sivakumar,

I have not personally used these post-processors in this way, but I see from the documentation that you can run MLife by accessing data without files, but I donât see similar documentation for running MExtremes this way. It appears MExtremes only supports OpenFAST *.out* and *.outb* formatted output files. If you wish to use MExtremes but are not running OpenFAST, I would suggest taking your time-series data and writing the data to one of these output file formats.

Best regards,