80 



c. Assumption of a fixed position (neglect of bodily rise 

 or sink and trim) . 



d. Assumption of a small height -length ratio of waves created 

 by the ship including neglect of the ship form above the water when 

 computing pressure. 



ACKNOWLEDGMENT 



This report presents only a skeleton of the subject; by studying the 

 numerous references which, however, do not include important experimental work, 

 it is possible to fill up to some extent the rather sketchy picture. Further, 

 it is hoped that some of the projects now under way at the David Taylor Model 

 Basin will lead to broader applications of the theory. This part of the re- 

 search work, due to its magnitude, must be carried out by large institutions; 

 the development so far has been hampered by the fact that individuals inter- 

 ested in the problems have only occasionally found the necessary support. 



The present investigation has been initiated and sponsored by the 

 Director of the Taylor Model Basin, Rear Admiral CO. Kell, USN, the former 

 head of the Hydromechanics Laboratory, Captain F.X. Forest, USN, and the Chief 

 Naval Architect, Dr. F.H. Todd, to whom the author wishes to express his sin- 

 cere thanks. Dr. Todd's help was essential in completing this ample report. 



APPENDIX 1 

 THE EQUATION OF THE SHIP SURFACE 



The axes are chosen as shown in Figure 1 . Then the equation of the 

 hull surface may be written 



y = ± y(x,z) 



[1] 



Figure 1 - Axes of Reference 



