Tuok and Taylor 



ship in beam seas in the form 



F2 = - 2L 



aphy_ 



<(>(x,0^, -h) dx. 



(7.1) 



Figure 4 shows computations of |F2|/2pghiA for the Series 60, 

 block 0.80 ship whose blockage coefficient C(x) was given in 

 Fig. 3. This particular scaling of the force was chosen so that the 

 high frequency or short wave limit kj? -^ 00 is 2.0. This limit cor- 

 responds physically to the case when the ship acts as a perfect 

 reflector many wavelengths long, so that a pure standing wave exists 

 in its neighborhood. This is true for all values of P(x) , i.e. for all 

 draft/water depth ratios, because as the waves get shorter and 

 shorter they are less able to penetrate beneath the hull. 



3.0 



HIGH FREQUENCY 

 ASYMPTOTE 



4.0 6.0 8.0 



k/ = ttL/X 



10.0 12.0 



Fig. 4 Side force on Series 60, block 0.80 ship, due to beam seas 



654 



