Please enable JavaScript.
Coggle requires JavaScript to display documents.
Wake (2/3) - Coggle Diagram
Wake (2/3)
Hadler Conclusions on wake
Wake pattern depends on AFT body
Harmonics
High order
lower amplitudes
Longitudinal velocity distribution
Lower values close to bossing
Higher close to tip
Tangential velocity variation
Large and sinusoidal
predominantly in 1st harmonic
can cause high shaft vibrations
Stern geometry
minimize cavitation and vibration
Open-type
Transom with strut
Propeller location
meaningful
Displacement and Trim
causes large variations in
vibration
cavitation
Nonuniformity
Blades rotation
generates
periodic forces
couples
trasmitted to hull
principal source of
hull vibration
vary angle of attack
causes cavitation
results in
vibration
noise
blade erosion
Magnitude
Single Screw
Higher
Up to w=0,75
Twin Screw
Lower
Higher behind strut or bossing
Nominal Wake
Measured without propeller
Effective Wake
Measured
with propeller
developing thrust