Yim 



REPLY TO DISCUSSION 



B. Yim 



Naval Ship Research and Development Center 



Washington, D.C. 



The author would like to acknowledge Prof. WeLnblum's 

 encouragement. The author fully agrees with him on everything he 

 mentioned. As is indicated in the text, the model of the transom 

 stern assumes the linear free-surface condition although, in 

 practice, very often nonlinear phenomena, e.g. , a rooster-tail or 

 cavity collapse, do occur. Therefore, this point also needs care, 

 in addition to the error in Mlchell's thin ship theory or the slender 

 ship theory. 



REPLY TO DISCUSSION 



B. Yim 



Naval Ship Research and Development Center 



Washington, D.C. 



The author sincerely appreciates the deep interest shown by 

 Drs. Sharma and Doctors regarding his paper. 



About the vadidity of Fig. 1 , the author will attennpt to make 

 a detailed explanation. First, the author would like to point out that 

 the discussers agree by their Eqs. (D6) and (D9) that, with p^/pg = 

 - 2irm/U, the potential due to a point sink located on the free surface 

 at X = and the potential due to the corresponding uniform pressure 

 distribution along the free surface from x=-ooto x = are 

 identical everywhere in the flow field and on the boundary. This fact 

 has long been known. Thus, velocities of the two cases are identical 

 everywhere, ajid the wave heights of the two cases are identical from 

 the relation (DIO). Namely, one problem with the given pressure 

 distribution is in fact the same problem with the properly given source 

 distribution as in many fluid mechanics problems. Admitting this fact, 

 it is impossible to claim that the representation by pressure gives 



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