在冰区桨设计过程中,往往需要对其桨叶边缘区域进行强度校核,防止与冰块接触过程中桨叶边缘出现缺口,对螺旋桨的水动力、空泡、噪声等性能产生影响.为了能够快速实现桨叶边缘强度校核,基于IACS URI3规范和有限元法(FEM),建立了集中冰载工况下的桨叶边缘强度校核方法.针对螺旋桨几何结构特殊性,将桨叶沿径向、弦向以及厚度方向划分成一系列八节点六面体单元,发展了螺旋桨有限元网格自动剖分方法,可以根据加载位置合理地进行网格划分,以FEM计算集中冰载作用下的桨叶应力和变形分布.以PC3级冰区桨为例,开展了桨叶边缘强度的分析和校核.计算结果表明:在集中冰载作用下桨叶边缘区域有较大应力集中,容易造成桨叶边缘区域的损坏.
During the design process of ice-class propellers, it is necessary to check the blade edge strength to avoid the gap on the blade under ice contact, which may affect the propeller performance of hydrodynamic force, cavitation, noise, etc. To quickly check the blade edge strength, based on the rules in IACS URI3 and the finite element method (FEM), the strength check method of blade edges is established under the concentrated ice load conditions. Considering the particularity of the propeller, an automatic meshing method has been developed by dividing the propeller into many 8-node hexahedron elements along radial, chordwise and thickness directions, which can help to mesh the propeller blades reasonably according to the loading position. The FEM is applied to calculate the stress and deformation distributions of the propeller blade under the concentrated ice load. Taking the PC3 ice-class propeller as an example, the blade edge strength is analyzed and checked. The results show that large stress is concentrated on the blade edge which is prone to cause the damage.
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