aircraft:tmd:airfoil
Differences
This shows you the differences between two versions of the page.
Both sides previous revisionPrevious revisionNext revision | Previous revision | ||
aircraft:tmd:airfoil [2017/03/02 11:10] – jh | aircraft:tmd:airfoil [2020/09/28 22:44] (current) – jh | ||
---|---|---|---|
Line 4: | Line 4: | ||
=== Other Aerodynamic classes === | === Other Aerodynamic classes === | ||
- | [[aerowing]], | + | [[aerowing]], |
===== Angle of attack ===== | ===== Angle of attack ===== | ||
- | The angle of attack (also known as AOA or α (" | + | The angle of attack (also known as AOA or α (" |
{{ Alpha.png? | {{ Alpha.png? | ||
Line 27: | Line 27: | ||
The lift coefficient Cl and momentum coefficient Cm increase linear with alpha in the Range of '' | The lift coefficient Cl and momentum coefficient Cm increase linear with alpha in the Range of '' | ||
The gradient of the lift coefficient in respect to alpha is '' | The gradient of the lift coefficient in respect to alpha is '' | ||
- | > Leave it at '' | + | > Leave it at '' |
{{ Airfoil_AttachedRange_ClAlpha.png? | {{ Airfoil_AttachedRange_ClAlpha.png? | ||
==== Cl0 ==== | ==== Cl0 ==== | ||
- | The '' | + | The '' |
> This attribute directly reflects the attitude in which an aircraft flies at high speed (low AOA). It also requires a larger down force from the horizontal stabilizer which increases the drag. It greatly affects the glide ratio. | > This attribute directly reflects the attitude in which an aircraft flies at high speed (low AOA). It also requires a larger down force from the horizontal stabilizer which increases the drag. It greatly affects the glide ratio. | ||
Line 42: | Line 42: | ||
==== CmAlpha ==== | ==== CmAlpha ==== | ||
- | The gradient of the momentum coefficient Cm is zero for symmetrical airfoils, positive for most typical airfoils that show movement of center of pressure (unstable) and negative for most airfoils with an s-bend (stable), used for flying wings. The '' | + | The gradient of the momentum coefficient Cm is zero for symmetrical airfoils, positive for most typical airfoils that show movement of center of pressure (unstable) and negative for most airfoils with an s-bend (stable), used for flying wings. The '' |
> The '' | > The '' | ||
> Typical '' | > Typical '' | ||
Line 49: | Line 49: | ||
==== Cm0 ==== | ==== Cm0 ==== | ||
- | '' | + | '' |
> With given geometry, incidence and fixed elevator position the '' | > With given geometry, incidence and fixed elevator position the '' | ||
Line 74: | Line 74: | ||
{{ Airfoil_AttachedRange_CdAlpha.png? | {{ Airfoil_AttachedRange_CdAlpha.png? | ||
- | ==== Flaps ==== | + | ==== AttachedCenterFlap |
- | === AttachedCenterFlap | + | |
The '' | The '' | ||
> Leave it at '' | > Leave it at '' | ||
Line 81: | Line 80: | ||
> Set a value that is lower to increase the effect of reversed ailerons near stall. | > Set a value that is lower to increase the effect of reversed ailerons near stall. | ||
- | === ClFlap === | + | ==== ClFlap |
'' | '' | ||
> '' | > '' | ||
Line 93: | Line 92: | ||
{{ Airfoil_AttachedRange_ClFlap.png? | {{ Airfoil_AttachedRange_ClFlap.png? | ||
- | === CmFlap === | + | ==== CmFlap |
'' | '' | ||
> Some aircraft need tremendous amount of negative '' | > Some aircraft need tremendous amount of negative '' | ||
Line 103: | Line 102: | ||
{{ Airfoil_AttachedRange_CmFlap.png? | {{ Airfoil_AttachedRange_CmFlap.png? | ||
- | === CdFlap === | + | ==== CdFlap |
'' | '' | ||
> Real life flaps always create additional drag when deflected. '' | > Real life flaps always create additional drag when deflected. '' | ||
Line 109: | Line 108: | ||
> | > | ||
- | <div id = " | ||
==== Table of flap coefficients ==== | ==== Table of flap coefficients ==== | ||
- | > These are just examples | + | Recommended values for the Aerofly |
- | ^ Type of flap ^ ClFlap | + | ^ Type of flap ^ ClFlap |
- | | Plain flap | + | | Plain flap |
- | | Split flap | + | | Split flap |
- | | Slotted flap | 0.8 ... 2.0 | + | | Slotted flap | 2.7 | 0.06 |
- | | Fowler flap | 1.4 ... 3.0 | 0.14 ... 0.3 | -0.73 | + | | Fowler flap | 2.7 ... 3.4 | 0.2 |
- | </ | + | |
- | ==== StallRange and beyond | + | ==== ClAlphaBase |
- | + | ||
- | === ClAlphaBase | + | |
The lift coefficient can be approximated with a sinus function with the wave length of '' | The lift coefficient can be approximated with a sinus function with the wave length of '' | ||
'' | '' | ||
> Decrease this value to get a greater wing drop in a stall and during spins. Lower values increase the dynamics of accelerated stalls and maneuvers. Also decrease CdAlphaBase. | > Decrease this value to get a greater wing drop in a stall and during spins. Lower values increase the dynamics of accelerated stalls and maneuvers. Also decrease CdAlphaBase. | ||
- | === CmAlphaBase === | + | ==== CmAlphaBase |
Follows the same principle as the ClAlphaBase attribute. Usually this value is negative and the airfoil creates a pitch down force when the angle of attack increases beyond the stall angle (stable). The aircraft will pitch down on its own and accelerate again. A positive value is destabilizing. | Follows the same principle as the ClAlphaBase attribute. Usually this value is negative and the airfoil creates a pitch down force when the angle of attack increases beyond the stall angle (stable). The aircraft will pitch down on its own and accelerate again. A positive value is destabilizing. | ||
'' | '' | ||
+ | |||
+ | > The lower the value of '' | ||
{{ Airfoil_Stall_ClAlphaBase.png? | {{ Airfoil_Stall_ClAlphaBase.png? | ||
- | === ClFlapBase === | + | ==== ClFlapBase |
The '' | The '' | ||
> Use the value to regulate the control surface authority in stall or at a high deflection angle. This increases the roll rate for aerobatic airplanes. (See '' | > Use the value to regulate the control surface authority in stall or at a high deflection angle. This increases the roll rate for aerobatic airplanes. (See '' | ||
- | === CdAlphaBase === | + | ==== CdAlphaBase |
The drag coefficient can be approximated with a sin^2 (sinus squared) function that repeats every '' | The drag coefficient can be approximated with a sin^2 (sinus squared) function that repeats every '' | ||
> Decrease the '' | > Decrease the '' | ||
Line 149: | Line 146: | ||
==== Minimal ==== | ==== Minimal ==== | ||
This will fall back to default values for all attributes. | This will fall back to default values for all attributes. | ||
- | < | + | < |
- | | + | ></ |
- | | + | |
| | ||
==== All ===== | ==== All ===== | ||
- | < | + | < |
- | <[string8][Name][AirfoilTip]> | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | < |
- | < | + | ></ |
- | ></ | + | |
aircraft/tmd/airfoil.1488449420.txt.gz · Last modified: 2017/03/02 11:10 by jh