螺旋桨流固耦合多目标优化设计

本文提出将NSGA-Ⅱ多目标优化算法应用于螺旋桨多目标优化设计,并通过面元法和有限元法实现螺旋桨流固弱耦合.通过计算安装在Seiun-Maru(一艘日本散货船)上的HPS大侧斜螺旋桨压力系数分布和压力脉动,考虑了流固耦合效应的计算精度要高于不考虑流固耦合效应,验证了考虑流固耦合的必要性.本文以螺旋桨效率、非定常力和重量作为目标函数,在满足水动力性能、结构响应和空泡性能等约束条件下,选取描述螺旋桨外形的6个参数作为设计变量,以此建立优化函数.在不同近似最优解和非设计点为初值的算例中,其结果均改善了所有目标函数,验证了本文方法的有效性、适用性和鲁棒性.本文提出的多目标优化方法将有助于提高设计效率,节省计算资源,可成为未来螺旋桨设计的有效工具.

Multi-objecitve optimizal design of ship propeller considering fluid-structure interaction

This paper presents a multi-objective optimization methodology that applies the Non-dominated Sorting Genetic Algorithm-Ⅱ(NSGA-Ⅱ) to propeller design, and realizes Fluid-Structure Interaction (FSI) weak-coupling based on Panel Method (PM) and the Finite Element Method (FEM). The necessary of FSI is validated by calculating pressure coefficient distribution and pressure fluctuation of HSP (a propeller installed on a Japanese bulk freighter - Seiun-Maru). The FSI results turn out to have higher precision than those without FSI. In the multi-objective optimization methodology, efficiency, unsteady force, and mass are chosen as optimum objectives under certain constraints. Effectiveness and robustness of the methodology are validated by running the program starting from nearly-optimum and off-design propollers respertively. The proposed multi-objective optimization methodology could be a promising tool for propeller design to help improve design efficiency and ability in the future.