Optimization of the lines of bulbous bow of a hull based on parametricmodeling and CFD calculation

LAN Linqiang1, LUO Weilin1,2

（1.School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou 350116， China;
2.Fujian Province Key Laboratory of Structural Performances in Ship and Ocean Engineering, Fuzhou 350116， China）

Abstract: Aiming at the problem of the traditional design of the bulbous bow of a hull, complete parameter modeling of the hull by using NURBS and the calculation of the hull resistance based on Rankine source panel method was investigated. A hybrid optimization strategy in combination of the design variables, constraints and optimization goal were analyzed. An automatic optimization platform at the ship design stage was constructed to optimize the lines of bulbous bow of a hull. The parameters of the lines of bulbous bow of a hull were automatically optimized and adjusted to meet the aim to reduce the wavemaking resistance by using the automatic optimization platform. A lines of bulbous bow of a hull of a roro ship was optimized by using the optimization method proposed, with the objective to minimize the wavemaking resistance. The results indicate that wavemaking resistance reduces obviously and the waveshape of near bow becomes gentle after the lines of bulbous bow of a hull are optimized, which demonstrates the validity of the proposed optimization design strategy.

Key words: hull forms optimization; parametric modeling; CFD calculation; wavemaking resistance