Similarly for the afterbody with a parallel length |. 



[H5] 



1 r / ^ " lM \" 



[46] 



APPENDIX 2 

 FORMULAS FOR THE WAVE RESISTANCE 



All formulas here collected are valid for uniform motion only. 

 A. The Wave Resistance of a Source or Sink* 



Figure 39 " Source (sink) Beneath the Surface 



The flow due to a single source or sink has been studied by Have- 

 lock.®''" Assume the usual axes but with OZ directed vertically upwards (that 

 is the direction used in almost all Havelock's papers contrary to Michell's 

 assumption) . 



The velocity potential of a source m moving with a constant speed 

 v in the direction of x at a distance f beneath the surface can be written in 

 the form 



+ <^ 



[1 



♦Unfortunately there is no easily readable Introduction into the theory of wave resistance in any 

 Western language. Lamb's book stops just when matters become interesting for practice. 



