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(→Function inputs: added wing area) |
(→Stall hysteresis, normalized:: slight improvement in stall-hyst-norm explanation) Tags: Mobile edit Mobile web edit |
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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 ( | 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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