盘式拉杆转子非连续界面的功能失效机理及设计方法研究

Heavy duty gas turbine is a kind of clean and efficient power generating equipment. It is a strategic high technology related to national energy and defense security which development needs multi-discipline progress. Disk-rod-fastening rotor is the key component of heavy duty gas turbine, for which the conventional methods for rotors are no more effective because of the existence of discontinuous interface between disks. Up to now, there are still arguments on the layout of tie-rod, one central through-bolt or multi circumferential tie-rods, and on the way of torque transmission, Hirth teeth or simple frictional surface. In this project, large power transmission interface of both Hirth teeth and frictional surface will be studied, with emphasis on function failure mechanism and design method of these discontinuous interfaces. Firstly, the interfaces between disks will be analyzed by 3-D finite element method considering contact effect and surface morphology. According to the calculation, it is to be revealed the law of contact status shift between sticking and micro-slipping corresponding to generalized forces on interfaces, and then establish the nonlinear constitutive model with the discontinuous interfaces considered. Secondly, the models for determining static and dynamic characteristics of tie-rod rotor will be established, with the coupling interface modeling by thin layer elements. It's expected to find out the interaction mechanism between interfaces and the static and dynamic behavior of the disk-rod-fastening rotor both theoretically and experimentally. Finally, it is to reveal the failure mechanism of the coupling interface, and set up design criteria and method for coupling interface configuration and pre-tightening force of tie rods. The investigation of the project will promote independent design capability and original innovation ability of rotor systems for the development of national heavy duty gas turbine.

重型燃气轮机是清洁高效的发电装备，属多学科推动的战略高技术，其发展涉及到国家的能源和国防安全。盘式拉杆组合转子是重型燃机的核心部件，其非连续性导致传统的转子分析方法不再适用。目前，选择端面齿还是简单摩擦面传扭，尚存在争议。本项目以端面齿和摩擦连接两类大功率传递界面为研究对象，重点研究拉杆转子轮盘间非连续界面的功能失效机理和设计方法。首先，采用三维接触有限元法，并考虑表面形貌，揭示接触界面状态随广义力由粘滞向局部滑移转变的规律，提出含非连续界面薄层的非线性本构模型。然后，采用薄层单元模化耦合界面，建立拉杆转子静、动力特性的计算模型，从理论和实验两个层面揭示界面和组合转子静、动力特性等宏观使役行为之间的相互影响规律。最后，揭示非连续界面的功能失效机理，提出轮盘界面的设计准则，形成界面的设计方法，为盘式拉杆组合转子的设计提供理论依据，提高我国重型燃机的自主设计水平。

重型燃气轮机是清洁高效的发电装备，属多学科推动的战略高技术，其发展涉及到国家的能源和国防安全。盘式拉杆组合转子是重型燃机的核心部件，其非连续性导致传统的转子分析方法不再适用。本项目以大功率传递界面为研究对象，重点研究拉杆转子轮盘间非连续界面的功能失效机理、设计方法和界面失效的识别。.研究了拉杆转子非连续界面大功率传递、广义力传递机制和界面功能失效机理。采用三维接触有限元法分析了拉杆转子非连续界面的接触状态和接触应力，发现界面存在一种“扭转屈服”现象；在预紧力确定的情况下，界面承受剪力、弯矩、扭矩等载荷能力存在临界值，超过临界值，则界面功能失效；不同载荷下界面失效模式不同。通过研究掌握了影响界面承载能力的关键因素，阐明了拉杆组合转子轮盘间非连续界面大功率传递和广义力传递机制。.研究了界面参数对转子宏观力学行为的影响规律。提出了界面法向刚度、切向刚度计算模型，考虑了界面参数对刚度的影响；提出了非连续界面局部脱离时界面刚度计算的半解析算法。考虑界面效应和界面局部脱开的影响，研究了转子的宏观力学行为。.研究了盘式拉杆转子宏观力学行为的快速计算方法。提出了适用于大功率盘式拉杆转子模态和振动响应计算的多重分层模态综合法，该方法考虑了结构旋转、预应力、周期循环对称等特点，并验证了该方法的正确性。.研究了拉杆转子界面局部损伤的识别方法。提出了拉杆转子界面局部损伤识别的广义柔度矩阵法，该方法可采用非第1阶单阶模态来识别。考虑测量噪声、多处和轻微损伤的问题，提出了基于多尺度数据融合理论的损伤识别方法。并将这两种方法应用于拉杆转子界面局部失效识别。.通过研究揭示了界面功能失效机理，提出了非连续界面的设计原则，初步形成了界面设计方法，为盘式拉杆组合转子的设计提供理论依据，提升我国燃气轮机核心部件的设计水平和自主研发能力。