Airfoilprep vs. Foilcheck

[Claudio.Pedrazzi]

Hi,
I am trying for the first time to use Airfoilprep for extrapolation of Clift and Cdrag curves. In the good old times I had used Foilcheck.
It seems to me that, if the user has only a limited amount of data (as in my case, where my angle of attack goes only up to about 15�, around the beginning of stall), Foilcheck would still be needed.

I quote from the first page of Airfoilprep:
“In some cases you may need to first use the FoilCheck worksheet to develop your table at high angles. If you do this, you should still repeat the FoilCheck calculation to get the appropriate dynamic stall parameters for the 3-D airfoil table.”

No problem at all, I kept the “old” Foilcheck executable, but I am asking myself why did you choose to eliminate it from your web page. Infact, if all what one needs is to extrapolate CL/CD/CM data from a small range to the complete 0-360�, just to go fast to a WTPERF simulation, Foilcheck provides a faster answer.

Actually I was not able to obtain this with Airfoilprep.

thanks a lot and… keep up the good work!
Best regards
Claudio

[Marshall.Buhl]

@cpedrazzi

It seems to me that, if the user has only a limited amount of data (as in my case, where my angle of attack goes only up to about 15�, around the beginning of stall), Foilcheck would still be needed.

The TableExtrap worksheet in AirfoilPrep provides that function.

@cpedrazzi

I quote from the first page of Airfoilprep:
“In some cases you may need to first use the FoilCheck worksheet to develop your table at high angles. If you do this, you should still repeat the FoilCheck calculation to get the appropriate dynamic stall parameters for the 3-D airfoil table.”

I don’t see that quote in AirfoilPrep_v2p2.xls. What version are you using?

@cpedrazzi

No problem at all, I kept the “old” Foilcheck executable, but I am asking myself why did you choose to eliminate it from your web page. Infact, if all what one needs is to extrapolate CL/CD/CM data from a small range to the complete 0-360�, just to go fast to a WTPERF simulation, Foilcheck provides a faster answer.

As far as I am aware, AirfoilPrep contains all the functionality of FoilCheck and more. We do not have the resources to maintain both programs.

Please ensure you are using the latest version of AirfoilPrep. If you have additional questions, please do not hesitate to ask.

Marshall

[Claudio.Pedrazzi]

@mbuhl

I don’t see that quote in AirfoilPrep_v2p2.xls. What version are you using?

Marshall,
thanks for your answer. I will try harder…
the quote comes from about the middle of the “ReadMe” introduction of AirfoilPrep_v2p2.xls and says

“After the 2-D characteristics are established for the correct airfoil section and Reynolds number, the 3-D rotation effects should be accounted for. This is done by copying and pasting the 2-D (blended) table into the 3DStall worksheet, entering the necessary parameters (all shown in red), and running the macro (click on the yellow ‘Calc. 3-D Table’ button). The input table to this calculation should extend to reasonably high angles of attack (30-50�). In some cases you may need to first use the FoilCheck worksheet to develop your table at high angles. If you do this, you should still repeat the FoilCheck calculation to get the appropriate dynamic stall parameters for the 3-D airfoil table.”

Best regards
Claudio

[Marshall.Buhl]

@cpedrazzi

the quote comes from about the middle of the “ReadMe” introduction of AirfoilPrep_v2p2.xls and says

I suspect the ReadMe worksheet contains a typo in that it refers to the FoilCheck worksheet instead of the TableExtrap worksheet. I will verify this with Craig Hansen, the spreadsheet’s author.

Marshall

[Marshall.Buhl]

@mbuhl

I suspect the ReadMe worksheet contains a typo in that it refers to the FoilCheck worksheet instead of the TableExtrap worksheet. I will verify this with Craig Hansen, the spreadsheet’s author.

Craig verified my suspicions. I will fix the ReadMe sheet in the workbook and upload the revised version to eliminate the confusion.

Marshall