Differences

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--- aircraft:tmd:aerofuselage [2017/01/23 18:08] – [Flight in high angle of attack] jh
+++ aircraft:tmd:aerofuselage [2018/09/30 13:33] – [All] jh
@@ Line 1: / Line 1: @@
 ====== Aerofuselage ======
-Objects from the ''aerofuselage'' class create lift and drag based on their geometry. In knife edge flight the aerofuselage creates the greatest amount of lift compared to all other aerodynamic objects. Like an airfoil the aerofuselage has a lift coefficient, in fact two even. One for the side forces (y-direction) and one for the up/down forces (z-axis). It also has a drag coefficient for each of the axis.
+Objects from the ''aerofuselage'' class create lift and drag based on their geometry, coefficients, airspeed and attitude relative to the airflow direction. All larger objects in the Aerofly FS 2 Flight Simulator, that create significant amounts of lift and drag and each use their own ''aerofuselage'' object. Those larger aircraft parts could be the main fuselage, the closed engine cowlings like the ones in twin engine aircraft, but not the nacelles of turbofan engines. Nacelles can currently not be modeled due to their ring like shape.
-=== Other Aerodynamic classes ===
+In knife edge flight or high angles of attack the ''aerofuselage'' creates the greatest amount of lift compared to all other aerodynamic objects. Like an airfoil the aerofuselage has a lift coefficient, in fact two even. One for the side forces (y-direction) and one for the up/down forces (z-axis). It also has a drag coefficient for each of the axis.
-[[aerowing]], [[airfoil]], [[airbrake]], [[propeller]], [[aerodrag]], [[bladeforce]], [[bodyaerodynamics]]
+=== Other aerodynamic classes ===
+[[aerowing]], [[airfoil]], [[airbrake]], [[propeller]], [[aerodrag]], [[bladeforce]]
 ===== Stations =====
@@ Line 30: / Line 32: @@
 {{ :aircraft:tmd:aerofuselagecdx.png?nolink |}}
+----
 ==== Flight in high angle of attack ====
+At a great angle of attack the large geometry of a fuselage can create significant amounts of lift and drag. In the Aerofly FS 2 these affects are simulated and can be fine tuned using the ''Clz'', ''Cdz'' and also the ''Cm'' value (see below).
+{{ :aircraft:tmd:aerofuselagecz.png?nolink |}}
 === Clz ===
@@ Line 55: / Line 64: @@
 > A lower value increases a gliders performance at higher angle of attack, which is the case for tight turns in a thermal.
-{{ :aircraft:tmd:aerofuselagecz.png?nolink |}}
+----
 ==== Knife Edge flight ====
+During a knife edge flight the fuselage of an aircraft is hit sideways at an angle and can act like an airfoil depending on its shape. In the Aerofly FS 2 this is modeled by the aerofuselage shape parameter, its geometry defined by the stations and fine-tuned by the values below.
+{{ :aircraft:tmd:aerofuselagecy.png?nolink |}}
+=== Cly ===
+''Cly'' is the lift coefficient of the fuselage for sideways streams of air (side-slip, y-axis). The greater the value the more side force the fuselage produces at a given side slip angle.
+> ''0.6'' is a good initial value.
+> With higher values the airplane requires less side slip angle to maintain altitude in the knife edge flight. Use a moderate value for aerobatic airplanes to make them more realistic and also more agile.
 === Cdy ===
@@ Line 73: / Line 93: @@
 With a ''Cm'' value greater than ''0.0'' the aerofuselage destabilizes the aircraft around the y and z axis. With a value lower than ''0.0'' it stabilizes the flight path.
-{{ :aircraft:tmd:aerofuselagecy.png?nolink |}}
+> A ''Cm'' of ''0.0'' or slightly positive is the most realistic value because the majority of the moment of the fuselage is already calculated by the geometry described by the stations and its relative positioning to the [[rigidbody#center_of_gravity|center of gravity]] of the entire aircraft.
+> The ''Cm'' of the fuselage is not the ideal parameter to make an aircraft more agile around the pitch axis. Use [[aerowing#downwash|aerowing downwash]] and the [[airfoil#cmalpha|airfoil CmAlpha]] parameters.
+=== Propeller ===
+The ''LateralForceCoefficient'' and ''LateralDragCoefficient'' of a [[propeller]] also have a large influence on the knife edge flight. (Please see main topic about the [[propeller]] class)
+===== Example Code =====
+==== Minimal ====
+> **Caution**: Requires a [[rigidbody]] with the name ''Fuselage''
+<code>           <[aerofuselage][FuselageAero][]
+                <[string8][Body][Fuselage]>
+                <[float64tmarray][StationX]     [ 0.0 -1.0 ]>
+                <[float64tmarray][StationY]     [ 0.0  0.0  ]>
+                <[float64tmarray][StationZ]     [ 0.0  0.0  ]>
+                <[float64tmarray][StationWidth] [ 0.0  0.2  ]>
+                <[float64tmarray][StationHeight][ 0.0  0.25 ]>
+                <[uint32tmarray][StationShape]  [ 1    1    ]>
+                <[float64][Cdx][0.05]>
+                <[float64][Cdy][1.20]>
+                <[float64][Cdz][1.20]>
+                <[float64][Cly][0.50]>
+                <[float64][Clz][0.50]>
+            ></code>
+==== All ====
+> **Caution**: Requires a [[rigidbody]] with the name ''Fuselage''
+<code>           <[aerofuselage][FuselageAero][]
+                <[string8][Body][Fuselage]>
+                <[tmvector3d][R0][ 0.0 0.0 0.0 ]>
+                <[tmvector3d][X0][ 1.0 0.0 0.0 ]>
+                <[tmvector3d][Y0][ 0.0 1.0 0.0 ]>
+                <[tmvector3d][Z0][ 0.0 0.0 1.0 ]>
+                <[float64tmarray][StationX]     [ 1.0  0.5  -0.5   -2.0  ]>
+                <[float64tmarray][StationY]     [ 0.0  0.0   0.0    0.0  ]>
+                <[float64tmarray][StationZ]     [ 0.0  0.0   0.0    0.0  ]>
+                <[float64tmarray][StationWidth] [ 0.0  0.2   0.1    0.05 ]>
+                <[float64tmarray][StationHeight][ 0.0  0.25  0.125  0.05 ]>
+                <[uint32tmarray][StationShape]  [ 0    1     1      0    ]>
+                <[float64][Cdx][0.05]>
+                <[float64][Cdy][0.8]>
+                <[float64][Cdz][0.8]>
+                <[float64][Cly][0.6]>
+                <[float64][Clz][0.6]>
+                <[float64][Cm] [0.0]>
+                <[float64][Offset][0.0]>
+                <[bool][HasSwimmer][false]>
+            ></code>