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Maik JUSTUS: replace underscore with hyphen in config keywords, to be

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consistent with the rest of YASim and almost all of fgfs
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mfranz 2006-10-28 21:14:52 +00:00
parent bfe3053f62
commit 46127405cb
1 changed files with 53 additions and 52 deletions
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105
Docs/README.yasim
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@ -482,11 +482,11 @@ rotor: A rotor. Used for simulating helicopters. You can have one, two
divided by the root chord. A taper of one is a
bar blade, and zero would be a blade ending
at a point. Defaults to one. [d/c]
rel_len_where_incidence_is_measured: If the blade is twisted,
rel-len-where-incidence-is-measured: If the blade is twisted,
you need a point where to measure the incidence angle.
Zero means at the base, 1 means at the tip. Typically
it should be something near 0.7
rel_len_blade_start: Typically the blade is not mounted in the
rel-len-blade-start: Typically the blade is not mounted in the
center of the rotor [a/R]
rpm: rounds per minute.
ccw: determines if the rotor rotates clockwise (="0") or
@ -504,33 +504,33 @@ rotor: A rotor. Used for simulating helicopters. You can have one, two
the aileron like function
mincyclicail: The minimum of the cyclic incidence in degree for
the aileron like function
airfoil_incidence_no_lift: non symmetric airfoils produces lift
airfoil-incidence-no-lift: non symmetric airfoils produces lift
with no incidence. This is is the incidence, where the
airfoil is producing no lift. Zero for symmetrical airfoils
(default)
incidence_stall_zero_speed:
incidence_stall_half_sonic_speed: the stall incidence is a function
incidence-stall-zero-speed:
incidence-stall-half-sonic-speed: the stall incidence is a function
of the speed. I found some measured data, where this is
linear over a wide range of speed. Of course the linear
region ends at higher speeds than zero, but just
extrapolate the linear behavior to zero.
lift_factor_stall: In stall airfoils produce less lift. Without
stall the c_lift of the profile is assumed to be
sin(incidence-airfoil_incidence_no_lift)*liftcoef;
lift-factor-stall: In stall airfoils produce less lift. Without
stall the c-lift of the profile is assumed to be
sin(incidence-"airfoil-incidence-no-lift")*liftcoef;
And in stall:
sin(2*(incidence-airfoil_incidence_no_lift))*liftcoef*...
...lift_factor_stall;
sin(2*(incidence-"airfoil-incidence-no-lift"))*liftcoef*...
..."lift-factor-stall";
Therefore this factor is not the quotient between lift
with and without stall. Use 0.28 if you have no idea.
drag_factor_stall: The drag of an airfoil in stall is larger than
drag-factor-stall: The drag of an airfoil in stall is larger than
without stall.
Without stall c_drag is assumed to be
abs(sin(incidence-airfoil_incidence_no_lift))*dragcoef1...
..+dragcoef0);
With stall this is multiplied by drag_factor
stall_change_over: For incidence<incidence_stall there is no stall.
For incidence>(incidence_stall+stall_change_over) there is
stall. In the range between this incidences it is
Without stall c-drag is assumed to be
abs(sin(incidence-"airfoil-incidence-no-lift"))...
..*dragcoef1+dragcoef0);
With stall this is multiplied by drag-factor
stall-change-over: For incidence<"incidence-stall" there is no stall.
For incidence>("incidence-stall"+"stall-change-over") there
is stall. In the range between this incidences it is
interpolated linear.
The airfoil of the rotor can be described in two ways. First you
@ -539,32 +539,32 @@ rotor: A rotor. Used for simulating helicopters. You can have one, two
values greater than the stall incidence. You could get strange
results.
pitch_a:
pitch_b: collective incidence angles, If you start flightgear
pitch-a:
pitch-b: collective incidence angles, If you start flightgear
with --log-level=info, flightgear reports lift and needed
power for theses incidence angles
forceatpitch_a:
poweratpitch_b:
poweratpitch_0: old tokens, not supported any longer, the result are
forceatpitch-a:
poweratpitch-b:
poweratpitch-0: old tokens, not supported any longer, the result are
not exactly the expected lift and power values. Will be
removed in one of the next updates.directly.Use "real"
coefficients instead (see below) and adjust the lift with
rotor_correction_factor.
rotor-correction-factor.
The way is to define the lift and drag coefficients directly.
Without stall the c_lift of the profile is assumed to be
sin(incidence-airfoil_incidence_no_lift)*liftcoef;
Without stall the c-lift of the profile is assumed to be
sin(incidence-"airfoil-incidence-no-lift")*liftcoef;
And in stall:
sin(2*(incidence-airfoil_incidence_no_lift))*liftcoef*...
...lift_factor_stall;
Without stall c_drag is assumed to be
abs(sin(incidence-airfoil_incidence_no_lift))*dragcoef1...
..+dragcoef0);
sin(2*(incidence-"airfoil-incidence-no-lift"))*liftcoef*...
..."lift-factor-stall";
Without stall c-drag is assumed to be
abs(sin(incidence-"airfoil-incidence-no-lift"))...
..*dragcoef1+dragcoef0);
See above, how the coefficients are defined with stall.
The parameters:
airfoil_lift_coefficient: liftcoef
airfoil_drag_coefficient0: dragcoef0
airfoil_drag_coefficient1: dragcoef1
airfoil-lift-coefficient: liftcoef
airfoil-drag-coefficient0: dragcoef0
airfoil-drag-coefficient1: dragcoef1
To find the right values: see README.yasim.rotor.ods
(Open Office file) or README.yasim.rotor.xls (Excel
file). With theses files you can generate graphs of the
@ -573,7 +573,7 @@ rotor: A rotor. Used for simulating helicopters. You can have one, two
in the internet. Parameters for the airfoils NACA 23012
(main rotor of bo105) and NACA 0012 (tail rotor of bo105?)
are included.
rotor_correction_factor:
rotor-correction-factor:
If you calculate the lift of a heli rotor or even of a
propeller, you get a value larger than the real measured
one. (Due to vortex effects.) This is considered in the
@ -611,29 +611,30 @@ rotor: A rotor. Used for simulating helicopters. You can have one, two
If you know the flapping angle for a given cyclic input you
can adjust this by changing this value. Or if you now the
maximum roll rate or ...
translift_maxfactor: Helicopters have "translational lift", which
translift-maxfactor: Helicopters have "translational lift", which
is due to turbulence. In forward flying the rotor gets less
turbulence air and produces more lift. The factor is the
quotient between lift at high airspeeds to the lift at
hover (with same pitch).
translift_ve: the speed, where the translational lift reaches 1/e of
translift-ve: the speed, where the translational lift reaches 1/e of
the maximum value. In m/s.
ground_effect_constant: Near to the ground the rotor produces more
ground-effect-constant: Near to the ground the rotor produces more
torque than in higher altitudes. The ground effect is
calculated as
factor = 1+diameter/altitude*_ground_effect_constant
number_of_parts:
number_of_segments: The rotor is simulated in number_of_parts
factor = 1+diameter/altitude*"ground-effect-constant"
number-of-parts:
number-of-segments: The rotor is simulated in "number-of-parts"
different directions.
In every direction the rotor is simulated at
number_of_segments points. If the value is to small, the
number-of-segments points. If the value is to small, the
rotor will react unrealistic. If it is to high, cpu-power
will be wasted. I now use a value of 8 for number_of_parts
and 8 for number_of_segments for the main rotor and 4 for
number_of_parts and 5 for number_of_segments for the tail
rotor. Number of parts must be a multiple of 4 (if not, it
will be wasted. I now use a value of 8 for
"number-of-parts" and 8 for number-of-segments for the main
rotor and 4 for "number-of-parts" and 5 for
"number-of-segments" for the tail rotor.
"number-of-parts" must be a multiple of 4 (if not, it
is corrected)
cyclic_factor: The response of a rotor to cyclic input is hard to
cyclic-factor: The response of a rotor to cyclic input is hard to
calculate (its a damped oscillator in resonance, some
parameters have very large impact to the cyclic response)
With this parameter (default 1) you can adjust the
@ -645,21 +646,21 @@ rotor: A rotor. Used for simulating helicopters. You can have one, two
rotorgear: If you are using one ore more rotors you have to define a
rotorgear. It connects all the rotors and adds a simple engine.
In future it will be possible, to add a YASim-engine.
max_power_engine: the maximum power of the engine, in kW.
engine_prop_factor: the engine is working as a pd-regulator. This
max-power-engine: the maximum power of the engine, in kW.
engine-prop-factor: the engine is working as a pd-regulator. This
is the width of the regulation-band, or, in other words,
the inverse of the proportional-factor of the regulator.
If you set it to 0.02, than up to 98% of the rotor-rpm
the engine will produce maximum torque. At 100% of
the engine will produce no torque. It is planned to use
YASim-engines instead of this simple engine.
engine_accell_limit: The d-factor of the engine is defined as the
engine-accell-limit: The d-factor of the engine is defined as the
maximum acceleration rate of the engine in %/s,
default is 5%/s.
max_power_rotor_brake: the maximum power of the rotor brake, in kW
max-power-rotor-brake: the maximum power of the rotor brake, in kW
at normal rpm (most? real rotor breaks would be overheated
if used at normal rpm, but this is not simulated now)
rotorgear_friction: the power loss due to fritcion in kW at normal
rotorgear-friction: the power loss due to fritcion in kW at normal
RPM
yasimdragfactor:
yasimliftfactor: the solver is not working with rotor-aircrafts.