基于数值计算的调距桨桨叶强度校核方法

针对复杂的螺旋桨几何外形和载荷分布,为解决其强度校核问题,首先,采用单向流固耦合CFD方法和有限元方法对螺旋桨的结构强度进行计算分析,通过与文献推荐的安全系数进行比较,验证了该方法的合理性;然后,采用此方法对设计的调距桨在设计工况和系柱工况进行强度校核,同时与校核规范进行比较。结果表明,和现有的强度校核规范相比,此方法能提供更多的调距桨结构强度信息。该方法是先求解RANS方程来获取桨模表面的水动力压力系数,然后划分实桨的有限元模型,再把压力系数插值到有限元网格节点上计算得到实桨表面的水动力载荷,同时施加离心力,求解得到最大等效应力和应变,从而计算得到安全系数,可为调距桨的强度研究提供一种数值计算手段。

Strength Checking Method of Controllable Pitch Propeller Blades Based on Numerical Calculation

Considering the complex geometry shape and load distribution of a propeller, this paper investi-gates the accurate solution to their strength checking problems. First, the CFD method of unidirectional flu-id-structure coupling and the finite element method are used to calculate and analyze the structuralstrength of propeller; next, by comparing with the document-recommended safety factor, the rationality ofthe method is verified; then, the proposed method is used to check the structural strength of the designedcontrollable pitch propeller on the bollard and design conditions, concurrently comparing with the specifica-tion check. Results show that this method, compared with the existing strength check specification, has theadvantage of providing more information on the structural strength. Specifically, the method is done by firstsolving the RANS equation and obtaining the hydrodynamic pressure coefficient of the propeller model sur-face, then dividing the finite element model of the real propeller, and finally interpolating the pressure coef-ficient to the finite element mesh node and calculating the hydrodynamic loads of the real propeller surface,simultaneously exerting centrifugal force, and solving the maximum equivalent stress and distortion, as wellas calculating the safety factor. The method is designed to the strength research of controllable pitch propel-ler to provide a means of numerical calculation.