Dimples On Model Aircraft Could Greatly Extend Range
Have they tried dimples on radio controlled aircraft? The size and
speed could designed around the magic Reynolds number = 100,000 where
the coefficient of drag drops precipitously.
Dimpling could vastly extent the range of large and slow as well as
small and fast radio controlled aircraft.
A competitive cyclist is the right size and speed for Nre = 100,000 so
dimple suits can work. Same for golf balls.
Nre = 100,000 for widebodies going 0.5 knots so dimples won't work
except on the runway.
From fluid mechanics the Reynolds number is the ratio of inertial
forces/viscous forces.
N re = Diameter X velocity X density of fluid/viscosity of fluid.
Bret Cahill
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