Announcing release of HARP_Opt code

Hello,

We are happy to announce that the HARP_Opt code is now available on the NWTC Design Codes webpage:
http://wind.nrel.gov/designcodes/simulators/HARP_Opt/

HARP_Opt (Horizontal-Axis Rotor Performance Optimization) is a MATLAB® code that utilizes a multiple-objective genetic algorithm and blade-element momentum (BEM) theory flow model to design horizontal-axis wind and hydrokinetic turbine rotors. Check out the website for a more detailed description of the HARP_Opt code.

Feedback and suggestions are welcome, and I will be happy to answer any usage and theory related questions concerning HARP_Opt.

Enjoy!

Danny Sale
email: sale.danny@gmail.com
phone: 865.719.0557

Hi Danny,

I have been evaluating Harp_Opt code more for verifying performance rather than designing a rotor per se. I like the functionality of the design sweep that the code performs and am trying to get optimal rpm regimen to operate a variable speed stall regulated turbine. I achieved this by applying upper and lower bounds to hold my pure airfoils at certain predetermined locations to correspond with the blade we have. I believe you suggested this approach in a recent post which validated the approach that I took.

The reason I am writing is because I am not sure about the airfoil data that I am using especially post stall. I did notice that in the airfoil data that you have supplied with the code, you have included the S819-S821 series data. However the header says that these are hydrofoils. Can this data be used for Wind turbines too? Or is this data specific to hydrokinetic turbines. Please let me know.

Thank you.

Subin Sethuram.

Hi Subin,

The S8xx data files are not specific to either wind or hydrokinetic turbines, they just include an extra column for minimum pressure coefficient (Cp_min) that is required to predict cavitation for hydrokinetic turbines. The only reason I labeled these files as “hydrofoils” was because of the inclusion of the extra Cp_min data, and also because the range of Reynolds numbers matched a specific hydrokinetic turbine I was working on at the time. There is no problem to also use these files for wind turbine analysis.

Danny Sale
University of Washington

Hi Danny,

Thank you for the prompt response. This information will be really really helpful for me. Just out of curiosity, have you or anyone you know used the S8xx family in any rotor design. If yes is there a paper which I can refer to? What I am really looking for is some validation of the airfoil data, if available. I would appreciate it if you could let me know. Thanks.

Subin.

Hi Subin,

Maybe somebody else knows, but I am not aware of any validation studies for the S819 - S821 airfoils you are interested in. This website http://wind.nrel.gov/airfoils/OSU_data/reports/ contains some reports for several other NREL airfoils, but not the particular ones you are interested in. The S8xx data files included with HARP_Opt were computed using XFOIL, so I would not expect the data to be very accurate near peak lift or in the post stall region.

Danny Sale
University of Washington

Hi Danny,

I have been to the website you indicated and as you mentioned they have not tested this particular set of airfoils. I have gotten similar feedback from various other NREL staff that I have corresponded with in the past. However this was the first time that I saw a fully extended data set which is why I asked if someone had done further testing. Further since you mentioned those files were created under Professor Case VanDam’s supervision, I guess they are probably as good as any theoretical data will be. At least much better than if I attempted to do so. I was comparing some of the Xfoil runs that I did and my data seems to indicate higher lift and drag. But I am no aerodynamicist and I would trust the data coming out of UC Davis over mine any day. Once again thank you for all the information. It has been very helpful.

Subin.

I realise this is a somewhat old Announcement, but since there seems to be little on the forums about HARP_Opt I am hoping the right person will see this.

I am trying to use HARP_Opt to refine blade design. It runs fine until the optimisation completes and then I get this error:

Server creation failed. Invalid ProgID ‘excel.application’

which I assume is because I don’t actually have Excel installed on my new computer yet. The user guide says excel must be installed but I am hoping there is a workaround since that was written 5 years ago.

Is there an easy way to get it to only output the data as text files (which I can then open in OpenOffice Calc as I already have that installed) or, alternately, to get it to use OpenOffice Calc instead?

Hi Monika,

you are correct the error is probably about not having Excel installed. Fortunately, v3 of HARP_Opt alleviates many of the toolboxes and dependencies that v2 required. Hopefully you can try it and it solve your trouble, the newest Matlab version is here:https://github.com/NREL/HARP_Opt and there is also a python version here: https://github.com/andrewning/HARP_Opt. v3 writes output in more accessible format via the “xlwrite” function http://www.mathworks.com/matlabcentral/fileexchange/38591-xlwrite–generate-xls-x–files-without-excel-on-mac-linux-win, so Excel is not required anymore.

best,
Danny

Danny,

That is excellent news. Thank you very much.

Monika

Hi Danny,

When I try to download version 3 my Avast virus scanner claims it is infected with PDF:UrlMal-inf [Trj] in the development plan pdf.

I have been able to download everything else, and assume it is probably a false positive (not taking any chances though) but thought you should be aware.

Thanks,
Monika