Optimum Speed of Tuna Long Line Fishing Boat for Designing

Abstract

This paper presents a mathematical method to get the optimum speed of tuna long line fishing boats which are usually designed by modification of a type ship. Through heoretical processes, the mathematical model for this purpose was constructed as follows:
V≅2ν_n/k₃ (1)
C≅2ηM/3f₁k₁D^2/3k₃³ (2)
V⁴+4V³-C=0 (3)
Here, ν_n is optimum navigating speed, k₃ is coefficient of navigating days, 1-η is ratio of calling days to navigating days, M is ship cost except fuel oil cost per day, f₁ is fuel cost per unit weight, D is average displacement and k₃ is coefficient of navigating days.
From the basic values of each parameter, the basic C and ν_n are calculated, which were denoted as C₀ and V₀, respectively. Then, corresponding curve of C/C₀:V/V₀ was made. Thus, by using this curve, the values of V and ν_n may be obtained easily, based on the values of C for the desired value of any parameter.
Parameters, the effects of which were shown in curves, should be determined severely by means of statistical disposal of actual data. Applying it to actually operated boats, this model was proved to have generality and effectiveness.