NOTATION 



c Chord length 



D Propeller diameter 



(F)jj nth harmonic amplitude of F 



^x,y,z Force components on blade in x,y,z directions 



Jq Effective advance coefficient based on torque identity 



Jj' Effective advance coefficient based on thrust identity 



Kq Torque coefficient, Q/(pn2D5) 



% Thrust coefficient, T/(pn2D'^) 



L Any of the measured components of blade loading 



Lpp Length between perpendiculars 



Ly Wavelength 



(M)n nth harmonic amplitude of M 



^,y,z Moment components about x,y,z axes from loading on one blade 



n Propeller revolutions per unit time 



R Radius of propeller 



r Radial coordinate from propeller axis 



Tg Period of encounter of waves 



T^ Period of pitching 



t Time 



t(r) Maximum thickness of propeller blade section 



V Model speed or ship speed 



y^ Propeller speed of advance 



Vq Vertical component of the spatial average crossflow velocity 



in propeller plane in calm water without ship motions 

 Vj.(r,0^^) Radial component of wake velocity at propeller plane, 



positive towards hub 

 Vt(r,e^j) Tangential component of wake velocity at propeller plane, 



positive counterclockwise looking upstream for starboard 



propeller (right-hand rotation) , positive clockwise looking 



upstream for port propeller (left-hand rotation) 

 (Vt)j^ nth harmonic amplitude of V 

 Vy Wave velocity 

 Vx(r,0y) Longitudinal component of wake velocity at propeller plane, 



positive forward 

 Vw, Maximum vertical velocity component of propeller resulting 



from hull pitching motions 

 Wq Taylor wake fraction determined from torque identity 

 Vf Taylor wake fraction determined from thrust identity 



Wy^ Wake fraction determined from volume mean longitudinal 



velocity component through propeller disk determined from 



a wake survey, (V-V-^) /V 

 x,y,z Coordinate axes rotating with propeller; see Figure 2 

 Z Number of blades 

 ? Instantaneous wave elevation, positive upward from undisturbed 



surface 

 C^ Wave amplitude 



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