Original scientific paper
Form Factor Determination of the Full, Large Breadth and Shallow Draught Ship Series
Nastia Degiuli
Neven Hadžić
Marta Pedišić Buča
Gordana Semijalac
Abstract
By using the traditional approach, the total resistance can be broken down into Froude and Reynolds number dependent components. These are then scaled according to their respective scaling laws. The common practical method of separating the resistance components is by the use of a form factor to estimate the total viscous component. This paper presents the form factor determination of the full ships with large breadth and shallow draught for full load and ballast
conditions using Prohaska's method. Form factors have been determined from the results of resistance tests carried out in Brodarski institute with ship models of the Jelsa series. Since full
ships with block coeffi cients CB > 0.8 are concerned, higher powers of the Froude number, n = 4 ÷ 6, have been used in the expression for the wave resistance. Obtained values for the total resistance have been compared with measured ones. It has been shown that all three powers give satisfactory agreement of results.
Keywords
form factor; Prohaska's method; total resistance; viscous resistance; wave resistance
Hrčak ID:
19471
URI
Publication date:
25.12.2007.
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