





























0.12 



















p = Parobolic Form 

 p = 0.4762 Full Form 









\ 



\ 













v-; 



R 











3pg B 2 H 2 



0.8 







\\ 













TT L 











\\ 

























0.4 







\v 







\p = 0.4762 

























p=0 

















































12 



V 



Figure 4 - Comparison of Wave Resistance Coefficients 

 of Parabolic and Full Forms 



To obtain a better basis of comparison between theory and experiment, it was suggest- 

 ed that the influence of the sharp corners on the resistance should be eliminated by towing 

 the model at a shallower draft H = 20 inches. Then the measured and calculated differences 

 in resistance for the two drafts could have been calculated. However, it was not feasible to 

 tow the model at a shallower draft at the time the tests were run . 



WAVE PROFILES 



The work done on the calculation of the wave profiles of the friction body was based 

 upon information given by W.C.S. Wigley. 5 His investigations were performed upon a body 

 having a short parallel middle body, 1/16 of the total length, and parabolic ends. 



Since the subject of wave profiles has not been treated as frequently as that of wave 

 resistance, the computations are presented here in detail. 



Two formulas given by Wigley in dimensional form were used in the calculations of the 

 wave profiles. The first gave the surface elevation due to wave making and the second the 

 symmetrical disturbance. 



In dimensionless coefficients these become 



8b 



-P - 1 { r (^-l + p)]-F - 1 {y(^-2)}+P - 1 { y (^-l- P )}] 



[6] 



