Application of Wavemaking Resistance Theory 



would encourage the use of the linear theory, as long as it gives satisfactory re- 

 sults. Intuitively I would agree with Dr. Pien that a ship of small wave resist- 

 ance will probably have less associated nonlinear effects from the free surface 

 than another ship of the same principal dimensions but larger wave resistance. 



DISCUSSION 



Lawrence W. Ward 



Webb Institute of Naval Architecture 



Glen Cove, Long Island, New York 



Dr. Pien has presented a very stimulating paper and one which I feel is es- 

 sentially correct, but I would like to take this opportunity to discuss two points 

 which I feel are of importance in connection with this work and with some of the 

 other papers given this afternoon as well. 



The first point is that of the question of the definition of wave resistance 

 which is essentially that of the definition of wave resistance in real fluid since 

 in the case of an ideal fluid all definitions seem to lead to the same resvilt. 

 There are a number of definitions possible, depending on the use to which the 

 definition is to be put; and I would like to review this matter with you at the risk 

 of boring those who were at Ann Arbor with the help of a table similar to one 

 shown at that time (Fig. 1). Since the theory of wave resistance in a real fluid 



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Fig. 1 - Various breakdowns of ship resistance into components 



221-249 O - 66 - 74 



1141 



