Reducing thickness of wing in profili

[Swan]

I've been using other programs for airfoils for foam wings and just started feeling my way around profili,and i was wondering how i reduce the thickness of a airfoil?Thanks Swan

[mharms]

I've only been playing with Profili a little while, but this may help you:

Go to menu Airfoils and select "Airfoils Management".
The Airfoils Management window pops up.
From the list, select (highlight) the airfoil you want to modify.
Go up to the "Airfoils Management" window menu and select "Process".
Choose "Process Selected Airfoil".
The "Airfoil processing" window pops up (see image).
Here you can change the thickness.
Remember to give the modified airfoil a new name -- otherwise Profili will just keep appendong "-Mod" to the original name.

Also, when running type 4 polars, you can set the airfoil's max thickness from within the window you get from clicking on the "Set" button. This would be useful if you want to take the same airfoil and see the effects of stepping up/down the thickness. This doesn't actually change the airfoil in the database. Its just for running the polars.

(I assume you have registered your Profili. I'm not sure what functions are disabled in the unregistered version)

Mark

[Swan]

Thanks very much.Swan

[flyingwings]

Thanks very much.Swan

Swan

Just a caution when using the Process functions. When you change the thickness or position of thickness or any of the other functions you may also unknowingly alter the leading edge in such a manner that you don't have a smooth entry.

Each time I make a change to any of the airfoil parameters I will go to the Management pull down and then to Modify the external shape graphically. Zoom into the leading edge. You may be very surprised to see a very out of shape entry ramp. You can modify the shape by changing the data points on the two graphs that are shown in that window.

For a comparison of what a leading edge should look like go to Mark Drela's AG 12 Super Gee Airfoil. Mark's leading edge design is the best to emulate.

Always compare to Dr. Drela's airfoils as they seem to be able to achieve the lowest drag numbers for the particular Reynolds Number.

Note that an airfoil design is very Reynolds number sensitive within 100,000.

Paul