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POSITION OF LCB 



Figure 9 - Ratio of for Different 



Values of Cn and Positions of LCB 















































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AFT 



1 1 



FORWARD— 



1 1 



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2 5 2.0 1.5 1.0 0.5 (3) 5 10 1.5 2.0 2.5 3.0 i5 

 POSITION OF LCB 



Figure 10 - Ratio of for Different 



Values of C g and Positions of LCB 

 In order to use the contours to obtain a model having any desired fullness and location 

 of LCB , certain auxiliary curves are necessary. These show. 



1. the ratio of length of entrance to total length (Figure 9) and 



^BP r 



2. the ratio of entrance and run prismatic coefficients — for different block 



C 



PR 



coefficients and positions of LCB (Figure 10). 



In a particular case, the dimensions and displacement of the ship and the desired loca- 

 tion of the LCB will be determined first from the general design conditions. A number of 

 different solutions may be tried to explore the effects on horsepower, weights, costs, and so 

 on. In any one case, the block, midship area, and prismatic coefficients can be calculated 

 and the length of parallel body (^ y) *^^" ^^ found from Figure 3. Figures 9 and 10 will then 

 give the length of entrance (L^) and the ratio of prismatic coefficients of entrance and run 



C 



PR 



We can then write 



'P >^ ^BP ~ (^PE '^ ^e) + ^x '^ (^PR 

 from which Cpg and Cp^ can be determined. 



Lr) 



IV-23 



