hello,

i was wondering how could i import airfoil files into gridgen? I have always used gambit and now I have decided to use Gridgen. Moreover since my study involves a "different" airfoil such as the DHMTU I was wondering if this airfoils has the same process as the NACA ones.

Thanks.

Naz.

hi ,how u where importing aerofoil in gambit is it ur importing aerofoil points or profile by itself

How airfoil files are imported depends on their format. If the airfoil shape is defined by a string of (x,y,z) points you can use Gridgen's segment file format (described in documentation) and import it either as a database curve or as a connector. If you have the curve in an IGES file, you can import that as a database.

Hope this helps.

thanks for your replies.

i was wondering if the airfoil tutorial in gridgen is a naca 0012? does anyone know???

another question is that I have my profile in a dat file with x y z coordinates. does anyone know what i need to do to import in Gridgen?

Thanks once again.

Nazario.

Nazario,

I don't know what airfoil is used in the Gridgen tutorial, but if you email support@pointwise.com they can probably tell you.

If you have an airfoil profile defined by (x,y,z) points, you can put them in a Gridgen segment file and import them as database (geometry). The format of segment files is described in the user manual, but it's a very simple ASCII format:

N

x1 y1 z1

x2 y2 z2

...

xn yn zn

M

x1 y1 z1

x2 y2 z2

...

xm ym zn

L

...

Hope this helps.

i cant seem to import mt dat file and i dont know why. I have problems when importing my DHMTU profile.

"An error occured during import. If due to incorrect attributes then make changes on the next menu and then press Done"

thanks for everything in advance.

Naz.

Give the file a .dat extension. That will help Gridgen automatically recognize it on import.

On the File Attributes menu, make sure the file type is set to "segment".

thanks I have done that. The file has a dat extension and I have selected segment but it wont import it!

any possibility that it has problems with the numbers after the comma. any chance I can send you the dat file?

thanks once again, Naz.

What comma? There are no commas in the segment file. Numbers on a line are delimited by spaces.

Yes, email the file to gridgen@pointwise.com.

thanks email just sent!

There are 4 things wrong with the file. Fixing 3 of them allows the file to be imported.

The first line of the file should only have one integer: the number of points. I deleted the 2nd integer (a 2).

One point's x coordinate was missing the decimal point.

One point's y coordinate had a space between the number and the exponent.

The fourth problem has something to do with a bad y coordinate for one point.

I wrote this in Notepad and saved it as a .dat file. I also cannot get it to import. Any thoughts?

integer 2 integer ni(2) real x(2), y(2), z(2)

do n=1, 2

write(1,*) ni(n)

do i=1, 2

write(1,*) x(i,n), y(i,n), z(i,n)

end do end do

1 3 0 2 5 0

It's hard to say what's wrong with the file based on psuedo-code.

The file format is simple ASCII:

number of points

x, y, z of 1st point, separated by spaces (no commas)

x, y, z of 2nd point

etc.

Email the file to gridgen@pointwise.com and I'll take a look.