基于三维干摩擦模型的失谐叶盘减振控制及不敏感设计方法研究

Turbomachinery such as steam turbines and gas turbines is an important symbol of the national industrial level, and the blade is the key component to realization of energy conversion. Due to the difference of the blade materials, machining, assemblies, resulting in bladed disk mistuned. The existence of mistuned has resulted in non-uniform transmission of blade vibration and energy, accelerated high cycle fatigue failure, seriously affect the safety and reliability of the unit. Dry friction damping structure has the advantages of simplicity in structure and independence of temperature, widely used in controlling of blade vibration. In this project, a three dimensional dry friction model which considering the effect of micro scale of the contact surface is established, based on the fractal theory and Hertz contact theory. Combining the three dimensional dry friction model, anti-aliasing hybrid frequency-time domain method and multi-modal method, the solution and analysis software is developed to predict the nonlinear vibration response of mistuned bladed disk with dry friction damping structure. The effects of frictional contact interface parameters on the dynamic behavior of mistuned bladed disk are investigated. The vibration characteristics of dual-mistuned bladed disk are studied. The dry friction damping experiment system of mistuned bladed disk is built, and the dry friction damping effects of the mistuned bladed disk are studied by the experiment system. The friction damping mechanism of mistuned bladed disk with dry friction damping structure is revealed by adopting the theoretical method and experimental results. The design criteria of dry friction damping control in mistuned bladed disk is set up, and insensitive design method of mistuned bladed disk is formed. The investigation of the project will provide a theoretical basis for the development of high performance steam turbine and gas turbine.

燃气轮机、汽轮机等叶轮机械是国家工业水平的重要标志之一，叶片是其实现能量转换的关键部件。由于叶片材料、加工、装配的差异，造成叶盘失谐。失谐引起叶片振动和能量非均匀传递，加速了叶盘疲劳失效，影响机组安全可靠性。干摩擦阻尼结构因不受温度限制、简单易实施等优点，广泛应用于叶片减振控制。本项目基于分形理论和Hertz接触理论，建立能够考虑接触表面微观尺度效应的三维干摩擦模型。综合三维干摩擦模型、抗混叠时频域融合算法和多模态降阶方法，开发干摩擦阻尼结构失谐叶盘非线性振动响应的高效计算分析软件，研究摩擦接触面参数对失谐叶盘宏观动力学行为的影响规律及双重失谐叶盘系统的振动特性；建立失谐叶盘干摩擦减振实验系统，研究失谐叶盘干摩擦阻尼减振效果；采用理论与实验相结合的方法揭示干摩擦阻尼结构失谐叶盘的减振机理，提出失谐叶盘减振控制设计准则，形成失谐叶盘不敏感设计方法，为研制高性能燃气轮机和汽轮机提供理论依据。

透平机械是国家工业装备中最为关键及核心的设备之一，广泛应用于冶金、石化、船舶、钢铁和电力等行业，在国民经济尤其是重工业体系中占有十分重要的地位。叶片是其实现能量转换的关键部件，由于其工作环境恶劣，结构复杂，叶片故障已成为透平机械设备中最为常见的故障之一，严重影响了机组运行的安全可靠性。本项目以失谐叶盘系统振动局部化所导致的叶片高周疲劳破坏的工程技术问题为研究背景，以含干摩擦阻尼结构的失谐叶盘系统为研究对象，通过对失谐叶盘系统振动特性的分析计算掌握了影响失谐叶盘系统振动局部化的关键因素。运用分形理论和Hertz 接触理论，研究摩擦接触表面的微观尺度效应，确定接触刚度、摩擦系数与接触面特征向量之间的函数关系，建立能够精细反映摩擦接触面运动状态的三维摩擦接触模型。该模型的建立突破了以往干摩擦阻尼减振研究中决定摩擦接触状态的关键参数依靠经验值或假设值的瓶颈，明晰了接触面的跨尺度摩擦行为和周期性激励的能量耗散机理。从计算精度和效率两方面对现有的非线性响应求解算法进行改进，提出了抗混叠时频域融合算法。结合摩擦接触模型、抗混叠时频域融合算法和多模态降阶方法，开发了含干摩擦阻尼结构失谐叶盘非线性振动响应的高效计算方法, 研究摩擦接触面参数对失谐叶盘宏观动力学行为的影响规律以及接触面摩擦失谐情况对失谐叶盘系统产生的二次影响。双重失谐叶盘系统振动特性的研究，真实还原了含干摩擦阻尼结构失谐叶盘系统工作的实际情况，补充该研究方向的缺失，研究结果可提升对阻尼结构失谐叶盘振动特性的全面认知，为研制高性能燃气轮机和汽轮机提供理论依据。