Lin, Paulling, and Wehausen 

 REFERENCES 



1. Lin, Wen-Chin; Webster, W. C; Wehausen, J. V. - Ships of minimum total 

 resistance. Proceedings, International Symposium on Theoretical Wave 

 Resistance, Ann Arbor, 1963. 



2. Gerter, Morton - A reanalysis of the original test data for the Taylor Stand- 

 ard Series. David Taylor Model Basin Report 806 (1954). 



3. Todd, F. H. - Series 60. Methodical experiments with models of single- 

 screw merchant ships. David Taylor Model Basin Report 1712 (1963). 



DISCUSSION 



p. C. Pien 



David Taylor Model Basin 



Washington, D. C. 



This paper gives us the theoretical and experimental results of two mini- 

 mum resistance models. It is quite clear as to how these results have been ob- 

 tained. However, it is not easy to digest these results. 



Why the theoretically predicted low resistance has not been obtained ex- 

 perimentally ? Why are the relative resistance qualities of these two models 

 just opposite to the theoretical predictions ? In explaining the results of the 

 symmetrical model the authors suggested the possibility of the second term in 

 the perturbation series being greater than the first term. If it is so then this 

 second term would also be much larger than the first term of the asymmetrical 

 model since the experimental results show that the symmetrical model has much 

 greater resistance than the asymmetrical model. This is not likely to be the 

 true situation. 



Based on Professor Inui's important research work, we know the linearized 

 ship-surface condition is not accurate for the beam value used in the paper. 

 Therefore the theoretical model of singularity distribution used in the wave- 

 making resistance computation is not in correspondence with the physical model 

 used in the experiment. In such situations, we should not be surprised to see 

 that the agreement between the theoretical and experimental resistance values 

 is not good. 



Based on the experience of Professor Inui as well as our own, I believe a 

 much better agreement between theoretical and experimental wavemaking resist- 

 ance results can be obtained, especially for the symmetrical case where the 

 free -surface disturbance is small and the Froude number is not too low, if a 

 higher order approximation is applied on the ship-surface. It would be interesting 



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