Assessment of Rule Length for Various Bow Forms: Longitudinal Strength via Long Term Analysis

The project investigates the dependence of vertical wave bending moment on the rule length, as proposed by classification societies, by providing a computational assessment in terms of long-term extreme values. Three distinct ship models are adopted for the study; the bows of the base models are modified to impose different forms, thereby introducing different rule lengths. Seakeeping analyses are performed for zero-speed and forward speed conditions. The mid-section extreme vertical bending moment values, calculated through long-term analyses, are compared to the rule-based values.

Key points of the project are given as follow:
• The ship models DTMB 5415, KCS, and KVLCC2 are selected to incorporate a wide range of design features.
• The DTMB 5415 model is not appropriate to assess the rule length.
• The calculated long-term extreme values and the rule-based values for the mid-section vertical bending moment don’t show a consistent agreement, most probably due to the nonlinear dependence of long-term values on the ship length and ship forward speed.

The related staff:
Prof. Bahadır Uğurlu
Res. Asst. Enes Tunca, Msc
Res. Asst. İsmail Kahraman, Msc
Res. Asst. Ramazan Tufan Azrak, Msc