Blade mean lift coefficient
Characteristics of a rotor obviously depend on the lift coefficient at which the blades are operating and it is useful to have a simple approximate indication of this. The blade mean lift coefficient provides such an indication. As the name implies the mean lift is that which, applied uniformly along the blade span, would give the same total thrust as the actual blade. Writing the mean lift coefficient as L we have, from Equation (3.12),
from which
The parameter CT/s is thus of fundamental importance and this explains the preference some workers have for using it as the definition of thrust coefficient (see Equation (3.18)) instead of CT. Expanding the definition gives
Characteristics of a rotor obviously depend on the lift coefficient at which the blades are operating and it is useful to have a simple approximate indication of this. The blade mean lift coefficient provides such an indication. As the name implies the mean lift is that which, applied uniformly along the blade span, would give the same total thrust as the actual blade. Writing the mean lift coefficient as L we have, from Equation (3.12),
from which
The parameter CT/s is thus of fundamental importance and this explains the preference some workers have for using it as the definition of thrust coefficient (see Equation (3.18)) instead of CT. Expanding the definition gives
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