关于热障涂层工况模拟试验涡轮模型设计的一些探讨

Exploration on Turbine Model Design of Thermal Barrier Coating Simulation Test of Working Condition

热障涂层是目前保护航空发动机内部热端部件、提高其热效率最常用的方法和发动机必备的关键技术之一.航空发动机热障涂层服役环境极其严苛,其剥落失效面临巨大瓶颈,研制热障涂层服役环境模拟装置是理解热障涂层机制的重点.该文基于航空发动机热障涂层热、力、化多场耦合等实际服役环境,探讨有关热障涂层工况模拟试验用涡轮模型的设计.该模型是热障涂层工况模拟装置的核心模块之一.主要内容如下:(1)基于动力学平衡原理,结合发动机两类叶片数量之比等比例设计导向、工作叶片热障涂层的数量和位置;(2)基于高温燃气与高速旋转交互作用后尾迹、湍流的位置设计导向叶片与工作叶片之间的夹角;(3)基于涡轮叶片高速旋转线速度来设计模型件关键部件,包括导向叶片、工作叶片、涡轮盘的尺寸;(4)基于不同试验目标与测试要求选用不同类型的涡轮模型,第一类模型适用于工作叶片热障涂层的模拟考核与导向叶片热障涂层检测,第二类模型适用于工作叶片热障涂层的检测与机制研究.

Thermal barrier coating is one of the most commonly used methods to protect the hot end parts inside the aeroengine and improve its thermal efficiency.The service environment of thermal barrier coating for aero-engine is extremely harsh,and its spalling failure is facing a huge bottleneck.The development of thermal barrier coating service environment simulation device is the key to understand the mechanism of thermal barrier coating.Based on the practical service environment of thermal,mechanical and chemical coupling of thermal barrier coating for aero engine,this paper discusses the design of turbine model for simulation test of thermal barrier coating.This model is one of the core modules of the thermal barrier coating working condition simulation device,and the main contents are as follows:(1)based on the principle of dynamic balance and combined with the proportion of the number of the two types of engine blades,the design guide and the number and position of the thermal barrier coating of the working blades are designed;(2)the included angle between guide blade and working blade is designed based on the position of wake and turbulence after interaction between high-temperature gas and high-speed rotation;(3)design key components of the model based on the high-speed rotating linear velocity of turbine blades,including the sizes of guide blades,working blades and turbine disks;(4)different types of turbine disk models are selected based on different test objectives and requirements.The first type of model is applicable to the simulation assessment of thermal barrier coating on working blades and the detection of thermal barrier coating on guiding blades.The second type of model is applicable to the detection and mechanism research of thermal barrier coating on working blades.