Motion and Resistance of a Low-Waterplane Catamaran 



-1.0211 

 -1.0254 

 -1.0554 

 -1.0742 

 -1.0854 

 -1.1054 

 -1.1154 

 -1.1254 

 -1.1274 

 -1.1274 



±y 



.295 

 .295 

 .295 

 .295 

 .295 

 .295 

 .295 

 .295 

 .295 

 .295 



where x, y, z are coordinates of a source point, and m.is the 

 point-source strength. The origin is taken at the midship section in 

 the center of a catamaran at the undisturbed free surface. 



Strut : 



2 3 4 5 



m(x) = 2. 8283x - 18. 3987x + 46. 3879x - 50. 5260x +19.8121x 



for forebody with < x < 1 



- m = 2. 31 I6|x | - 14. 7986|x| 2 + 39. 3606lx| 3 - 45. 2937|x| 4 + . . . 

 . . . + 18.420llx| 5 



for afterbody with -1 < x < 



In addition, there is a line source of 0. 01 at x = 1 and a 

 line sink of the same strength at x = - 1 . The singularity strength 

 is normalized on the base of a unit of forward ship speed and the 

 strut singularity distribution length as two units. The depth of the 

 previously described surface and line singularity distribution is 

 0. 099. 



The wavemaking resistance coefficient C w is normalized 

 by wetted surface rather than the length square of the strut. For the 

 purpose of direct comparison with the experiment al r esidual resis- 

 tance coefficient C r , it is plotted against V / -J L ; where L is 

 related to the main hull length. The theoretical wavemaking resis- 

 tance curve is shown in figure 11 . 



Model Experimental Results The experimental hull form 



501 



