Thesis Glider Details

Hey sir, how are you.  I've had to re-design my control system because I can no longer fit it into the airfoil I think I am going to use.  The following is a complete   I am looking into a very thin airfoil, with a chord around 15 to 20 centimeters.  The leading edge will be sharp and the thickness will be approximately 6% of the chord.  The bottom surface will be flat like a board.  Wing tips will be sharp and light (like leading and trailing edges).  The top surface will be a smooth curve to delay flow separation and I think i might incorporate a bleeder in the trailing edge to prolong trailing edge stall.  I am aware that leading edge stall (for thin airfoils) is more dangerous than that for thick airfoils, and causes a sharper drop in lift at high angles of attack; I don't know what to do about this but I'll keep thinking (possibly a fixed slat). 

I'm not sure if what I'm saying is insane or not, but after reading many articles on high lift gliders, I've got the feeling that this is the way to go.  However, I did not read any convincing reasons why the above is true but after thinking about the arguments, I've concluded that it is worth a shot.  One article mentioned that lift is only created by the bottom surface, and that the top surface is only used to prevent seporation.  I tested this with a simple paper airplane...  It flew like a charm and had no chamber.  I thought maybe it was do to the ratio of weight to planform area so I clipped the wings and threw it again.  The bloody thing flew, so I clipped and threw and clipped and threw and it kept flying.  I can't explain it with anything I have learned up till now.

This is why I would like to do some quick analysis in Fluent.  I believe that this is what we are lacking; definite information about the flight characteristics of super thin airfoils at super low reynolds numbers.  I would like to get started on this as soon as possible so if there is any fluent code that I may use to modify (instead of spending a month trying to learn it) I would be eternally greatfull.  Anything you can do to speed up the process of collecting 2-D airfoil data on a number of thin airfoils that I am designing would be great. 

As of right now, I believe that it is no longer usefull to use flaps to control the gliders roll or lift characteristics.  If the information I have gathered is correct, than increasing the chamber will affect the lift characteristic in a negetive manner.  Instead I feel it will be better to control roll and lift by changing the angle of attack of our wings.  But how can we do this?

Today I am re-designing the roll control mechanism to counter rotate each wing.  Hence, creating a difference in lift between each wing and causing a roll.  This will work because the flat airfoils that I have looked at all seem to have reletively constant moments, so different angles will produce different lifts without affecting the pitch.  By not affecting the pitch we avoid accidentaly falling into a region of unstable flight, and makes pitch control much easier.  The elevator will be a thicker airfoil with a high lift coeficient (and higher drag, possibly a 0015, or thicker), this should increase stability and offer a better response to elevon trim changes during flight (slow short movements).  Finally I'm thinking of using a large thin rudder (high aspect ratio) possibly a flat plate to keep it aligned into the wind at all times (I have yet to read anything about rudders, but if this report is correct, a thin, high AR rudder seems logical).-i'm looking into an H tail-

Sorry for the long e-mail, I look forward to hearing what you think about my current direction.  I'm excited to start testing the limits of thin airfoils, Im curious to know how thin we can make them while still being able to construct them.  

p.s.  I'm looking into different shape factors, and I'm liking alluminum.  I know how to weld, so using metals is not inconcievable.  If you have any material in mind (like composite) please let me know.  If thin airfoils prove good, maybe we can use a thin sheet of composite; or even fiber glass.