model Validation

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Vahid.Fazlollahi
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Organization: Shahid Beheshti University
Location: Iran, Tehran

model Validation

Postby Vahid.Fazlollahi » Fri Nov 24, 2017 12:55 am

Hi,
I want to validate my modeling with FAST but i dont know how can i do that.
Please, can any one help me to do that?

Thank a lot,
Last edited by Vahid.Fazlollahi on Wed Dec 06, 2017 1:47 am, edited 1 time in total.

Paul.Feja
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Re: How can i validate my modeling with FAST

Postby Paul.Feja » Fri Nov 24, 2017 4:55 am

Hello Vahid,

you should probably be more pecise. What would you like to validate? Your model setup, your simulation results, ...?

Vahid.Fazlollahi
Posts: 25
Joined: Mon Nov 20, 2017 1:47 am
Organization: Shahid Beheshti University
Location: Iran, Tehran

model Validation

Postby Vahid.Fazlollahi » Fri Nov 24, 2017 10:08 am

Hi Paul,
Im sorry i forgot tell about my device.
I modeled 660 Kw Vestas wind turbine. So, i want validate my modeling with FAST model. Actually, i want validate my simulation results.

Thanks a lot,
Last edited by Vahid.Fazlollahi on Wed Dec 06, 2017 1:47 am, edited 1 time in total.

Jason.Jonkman
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Re: How can i validate my modeling with FAST

Postby Jason.Jonkman » Fri Nov 24, 2017 8:46 pm

Dear Vahid,

I agree with Paul. Please clarify your question. From where you getting the data needed to validate your model? Under what conditions? What quantities of interest are you interested in validating? What's your validation metric?

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

Vahid.Fazlollahi
Posts: 25
Joined: Mon Nov 20, 2017 1:47 am
Organization: Shahid Beheshti University
Location: Iran, Tehran

model Validation

Postby Vahid.Fazlollahi » Mon Nov 27, 2017 10:51 am

Dear Jason,
Thank you very much for your quick reply,
I will send you more details.
Kind regards,

Satish.Jawalageri
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Re: model Validation

Postby Satish.Jawalageri » Mon Oct 12, 2020 3:29 am

Hi,

I have simulated the 5MW_OC3Mnpl_DLL_WTurb_WavesIrr.fst model in openfast corresponding to the data provided in https://www.nrel.gov/docs/fy15osti/63067.pdf. But I got the following results but doesn't match well with the result obtained in the paper corresponding to monopile and the load case here I am referring is 5.1 and I have attached the plots of Time vs OoPDefl1 and Time vs RootMyc1.

And is there any reference where I can validate the openfast model in terms of whether the model is aligned or not.

Thanks,
Satish J
Attachments
Comparison FAST.docx
(86.47 KiB) Downloaded 39 times

Jason.Jonkman
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Re: model Validation

Postby Jason.Jonkman » Mon Oct 12, 2020 6:58 am

Dear Satish,

Actually, it looks like your results are quite close, although there is a small difference in the mean values. I'm not aware that the NREL model and results from the paper you referenced were made available, although the model of the NREL 5-MW turbine atop the monopile from the FAST v8 CertTest and OpenFAST r-test are likely quite close to the model that was used in this paper.

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

Satish.Jawalageri
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Re: model Validation

Postby Satish.Jawalageri » Mon Oct 12, 2020 7:15 am

Dear Jason,

Thanks for your reply.

Does that mean the result obtained using openfast are correct?

Or how to validate the model (openfast) in terms of whether the output is correct?

Thanks,
Satish J

Jason.Jonkman
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Re: model Validation

Postby Jason.Jonkman » Mon Oct 12, 2020 7:58 am

Dear Satish,

Yes, I believe your answers are correct. I'm not sure what is causing the small difference in mean values (perhaps a different mean wind speed?), but overall the trends look correct.

If you want to plot your results against other OC3 participants, all results generated during the OC3 project are available on Google drive--see: https://drive.google.com/drive/folders/ ... 3RkZ3FHVlE (the FAST v8 results from the paper you referenced are not included here because these were generated after the OC3 project concluded, but the plots in that paper were made by comparing to the results stored in this Google drive).

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

Satish.Jawalageri
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Organization: University College Dublin
Location: Ireland

Re: model Validation

Postby Satish.Jawalageri » Mon Oct 12, 2020 8:49 am

Dear Jason,

Thanks for your reply.
I will check.

Thanks,
Satish J

Satish.Jawalageri
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Re: model Validation

Postby Satish.Jawalageri » Thu Oct 15, 2020 2:53 pm

Dear Jason,

I run the 5MW_OC3Mnpl_DLL_WTurb_WavesIrr.fst model using Openfast and thought of comparing the result which was obtained in the document which you sent for the load case 5.1 - Phase I Monopile with Rigid Foundation. The following are the results and looks like my simulation results are wrong. Please could you advice me on this and I have attached the relevant files and plots.

Thanks,
Satish J
Attachments
NRELOffshrBsline5MW_OC3Monopile_HydroDyn.rtf
(18.13 KiB) Downloaded 32 times
NRELOffshrBsline5MW_OC3Monopile_ElastoDyn.rtf
(13.03 KiB) Downloaded 36 times
5MW_OC3Mnpl_DLL_WTurb_WavesIrr.out.rtf
(953 KiB) Downloaded 35 times

Satish.Jawalageri
Posts: 117
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Organization: University College Dublin
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Re: model Validation

Postby Satish.Jawalageri » Thu Oct 15, 2020 2:56 pm

Dear Jason,

Continued....I couldn't able to add more than 3 files in my previous post. So I am attaching the result and fast file.

Thanks,
Satish J
Attachments
Screenshot (58).png
Screenshot (58).png (25.86 KiB) Viewed 1137 times
Screenshot (57).png
Screenshot (57).png (27.02 KiB) Viewed 1137 times
5MW_OC3Mnpl_DLL_WTurb_WavesIrr.fst.rtf
(7.24 KiB) Downloaded 30 times

Jason.Jonkman
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Re: model Validation

Postby Jason.Jonkman » Thu Oct 15, 2020 3:52 pm

Dear Satish,

Can you clarify what you are comparing your results too such that you believe your results to be wrong? Which figure from which document are you comparing to?

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

Satish.Jawalageri
Posts: 117
Joined: Sun May 31, 2020 4:57 am
Organization: University College Dublin
Location: Ireland

Re: model Validation

Postby Satish.Jawalageri » Fri Oct 16, 2020 8:28 am

Dear Jason,

Thanks for your reply.

I am comparing with the results obtained in the document which you sent earlier - https://drive.google.com/drive/folders/ ... 3RkZ3FHVlE (Document location - Task 23 OC3\Phase I Monopile with Rigid Foundation\Simulation Results\Rev 5 - Plus New Comers - Updated\SimulationResults_NREL_FAST). Load case considered for comparison is 5.1 (Task 23 OC3\Phase I Monopile with Rigid Foundation\Simulation Results\Rev 5 - Plus New Comers - Updated\LoadCaseMatrix_PhaseI_070112).

I plotted Time vs wave elevation and Time vs fore-aft moment at the mudline from results obtained in the above document and then I compared with simulation results which I have attached in the previous post.

Thanks,
Satish J

Jason.Jonkman
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Re: model Validation

Postby Jason.Jonkman » Fri Oct 16, 2020 9:26 am

Dear Satish,

OK, thanks for clarifying.

One big difference I see is that the original OC3 Phase I results for load case 5.1 assumed wave linearity (Airy waves). However, I see that you have enabled second-order wave-kinematics (WvDiffQTF = WvSumQTF = TRUE) in your analysis (hence why your wave elevation is not sinusoidal). The second differences is in regards to wave stretching. The original OC3 Phase I results included Wheeler stretching for the wave kinematics, however, this functionality is not available in the version of OpenFAST that you are running. The lack of Wheeler stretching will impact the wave loads and resulting bending moment at the mudline.

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


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