Aero input and outputs: Difference between revisions

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→‎Stall hysteresis, normalized:: slight improvement in stall-hyst-norm explanation
(→‎Function inputs: added wing area)
(→‎Stall hysteresis, normalized:: slight improvement in stall-hyst-norm explanation)
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         </hysteresis_limits>
         </hysteresis_limits>
</code>
</code>
stall-hyst-norm, normally at 0, switches to 1 at 17 deg (alpha-deg or corresponding alpha-rad value, different from alpha-wing-rad if wing incidence is not zero).
17 deg is typically the stall angle for a wing.
Later on, it returns back to 0 only when alpha-deg comes down to 5 deg. Close to the usual hysteresis behavior (typically iron magnetization, with magnetic field h corresponding to alpha angle for us), but the delay is not dependent on the max value attained by the variable alpha. A kind of 'rectangular' hysteresis loop, more simple but already good for aerodynamics (linear or turbulent) regimes.
stall-hyst-norm, normally at 0 ('good condition'), switches to 1 ('bad condition') at 17 deg (alpha-deg or corresponding alpha-rad value, different from alpha-wing-rad if wing incidence is not zero).
Later on, it returns back to 0 only when alpha-deg comes down to 5 deg (that is with some 'delay'). Close to the usual hysteresis behavior (usually, iron magnetization vs magnetic field, with magnetic field h corresponding to alpha angle for us), but the delay is not dependent on the max value attained by the variable alpha. A kind of 'rectangular' hysteresis loop, more simple but already good for aerodynamics (linear or turbulent) regimes.


This stall-hyst-norm (0 or 1 values) can then be used as a parameter for tables, to set some command sensitivity, lift coefficient,moment, etc, to hold longer in it's 'bad' condition even when the cause has ceased. Stall holds for a longer time, like turbulent regime in the real case.
This stall-hyst-norm (0 or 1 values) can then be used as a parameter for tables, to set some command sensitivity, lift coefficient, moment, etc, to hold longer in it's 'bad' condition even when the cause has ceased. Stall holds for a longer time, like turbulent regime in the real case.


Logically, the <max> value is close to the critical AoA for stall, but the lift curve and stall-hyst-norm are used independently.
Logically, the <max> value is close to the critical AoA for stall, but the lift curve and stall-hyst-norm are used independently.
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