离心压缩机再制造叶轮服役寿命预测模型及数值仿真研究

发布时间：2018-04-14 05:00

本文选题：再制造叶轮 + 服役寿命　；参考：《重庆大学》2013年博士论文

【摘要】：机械装备再制造是再制造产业发展和循环经济建设的重点技术领域，为此，国家重点基础研究发展计划（973计划）专门设立了“机械装备再制造的基础科学问题”项目（2011CB013400），以离心式压缩机为典型对象，开展机械装备再制造的若干基础科学问题研究，为再制造技术攻关提供理论依据。其中再制造零件寿命预测涉及多个学科领域，已成为机械零件再制造的技术关键之一，迫切需要相关理论和方法的支持。本研究在973项目研究课题之一“再制造零部件的寿命预测与再制造产品服役安全验证”（2011CB013400-5）的资助下，开展了离心式压缩机再制造叶轮服役寿命预测模型及数值仿真研究，为再制造叶轮服役机理分析、服役安全性能评价提供理论和方法支持。首先，在断裂力学和损伤累积理论的基础上，结合再制造叶轮工艺修复结构特征和服役特征载荷，提出一种再制造叶轮零部件服役寿命预测模型。将材料或试件现有的寿命预测方法拓展到再制造后的离心压缩机叶轮上，建立起包含面向多失效特征的再制造叶轮几何精确建模方法、基于计算域虚拟规划的再制造叶轮流道自适应网格划分方法、基于数值分析的再制造叶轮服役特征载荷求解方法和FE-SAFE寿命计算软件以及再制造工艺寿命修正试验的再制造叶轮服役寿命预测模型，为再制造叶轮服役安全性能判定提供一种理论方法。其次，针对再制造叶轮模型缺失或已有模型无法反应再制造特征的问题，提出了面向多失效特征的再制造叶轮几何特征精确建模方法，构建体现再制造工艺特征的再制造叶轮精确几何模型；在有限元误差估算理论、几何拓扑同坯原理的基础上，建立再制造叶轮几何关键区域识别准则和计算域虚拟规划算法，形成再制造叶轮零件的全六面体网格生成方法，对再制造叶轮精确几何模型进行网格划分，产生疏密有致的高精度再制造叶轮流道自适应有限元网格模型。然后，在有限元传热理论、弹塑性力学、微积分原理基础上，利用ANSYS仿真技术分析并讨论了再制造叶轮服役的四种典型特征载荷，包括再制造工艺诱发的残余应力载荷、装配产生的装配应力载荷、高速离心应力载荷和气体介质等效应力载荷。基于分析与模拟结果综合评判再制造叶轮的服役静态强度，，并为再制造叶轮服役寿命预测的载荷谱拟合提供幅值依据。最后，开展某型号大型离心压缩机再制造开式叶轮寿命预测的应用研究。根据再制造叶轮服役的五个阶段特性和四种典型特征载荷建立再制造叶轮服役的载荷谱曲线，利用再制造叶轮服役寿命预测模型对再制造叶轮服役寿命进行预测，并通过基体材料FV520B的激光熔覆试验所得寿命修正系数算出了再制造叶轮的可服役年限。同时，也讨论了再制造工艺载荷对叶轮服役寿命的影响。
[Abstract]:Remanufacturing of machinery and equipment is a key technical field in the development of remanufacturing industry and the construction of circular economy. For this reason,The National key basic Research and Development Program (the "basic Scientific problems in Mechanical equipment Remanufacturing") has been set up to carry out a number of basic scientific research on mechanical equipment remanufacturing, taking centrifugal compressors as the typical object.To provide theoretical basis for re-manufacturing technology research.Among them, the life prediction of remanufacturing parts involves many disciplines, and has become one of the key technologies in the remanufacturing of mechanical parts, which urgently needs the support of relevant theories and methods.In this study, the life prediction model and numerical simulation study of centrifugal compressor remanufacturing impeller were carried out with the aid of "Life Prediction of remanufactured parts and Service Safety Verification of Remanufacturing products" (2011CB013400-5), one of the research topics of 973 project.It provides theoretical and methodological support for service mechanism analysis and service safety performance evaluation of remanufacturing impellers.Firstly, based on the fracture mechanics and damage accumulation theory, a service life prediction model for remanufacturing impeller parts is proposed, which combines the structural characteristics and service characteristic loads of the remanufacturing impeller process.The existing life prediction method of material or specimen is extended to the impeller of centrifugal compressor after remanufacture, and a geometric accurate modeling method for remanufacturing impeller is established, which contains multi-failure characteristics.Adaptive mesh generation method for remanufacturing impeller runner based on computational domain virtual programming.Based on numerical analysis, the service life prediction model of remanufacturing impeller is presented, which is based on the calculation method of service characteristic load of remanufacturing impeller and FE-SAFE life calculation software, as well as the service life prediction model of remanufacturing impeller based on remanufacturing process life correction test.It provides a theoretical method for determining the service safety performance of remanufacturing impeller.Secondly, aiming at the problem that the model of remanufacturing impeller is missing or the existing model can not reflect the characteristics of remanufacturing, an accurate modeling method for geometric features of remanufacturing impeller is proposed, which is oriented to multiple failure features.Based on the finite element error estimation theory and the principle of geometric topology of the same billet, the key region recognition criteria and the virtual programming algorithm of the computational domain for the remanufacturing impeller are established.An all-hexahedron mesh generation method is formed for remanufacturing impeller parts. The precise geometric model of the remanufacturing impeller is meshed to generate a highly precise self-adaptive finite element mesh model for remanufacturing impeller runner.Then, on the basis of finite element heat transfer theory, elastoplastic mechanics and calculus principle, four typical characteristic loads of remanufacturing impeller are analyzed and discussed by using ANSYS simulation technology, including residual stress load induced by remanufacturing process.Assembly stress load produced by assembly, high speed centrifugal stress load and gas medium equivalent stress load.Based on the analysis and simulation results, the static strength of the remanufactured impeller is evaluated, and the amplitude of the load spectrum fitting for the service life prediction of the remanufacturing impeller is provided.Finally, the life prediction of open impeller for a large centrifugal compressor is studied.According to the five stage characteristics of remanufacturing impeller and four typical characteristic loads, the load spectrum curve of remanufacturing impeller service is established, and the service life prediction model of remanufactured impeller is used to predict the service life of remanufacturing impeller.The service life of the remanufactured impeller is calculated by the life correction coefficient obtained from the laser cladding test of the FV520B substrate material.At the same time, the influence of remanufacturing process load on the service life of impeller is also discussed.
【学位授予单位】：重庆大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：TH452

【参考文献】