TGO厚度和界面形貌对700℃新型涂层双管系统应力分布的影响

Effects of TGO Thickness and Interface Morphology on Stress Distribution of 700 ℃ Novel Coated Dual Pipe System

以700℃新型涂层双管系统为研究对象,采用有限元顺次耦合的计算方法,开展了热机载荷作用下TGO厚度和界面形貌对系统应力分布的影响研究。结果表明:TGO的厚度与其界面粗糙度均会对系统的Mises应力分布产生影响,但是与TGO厚度相比,粗糙度对TGO/BC界面靠近波峰处的Mises应力影响更加显著。此外,在TGO界面幅值和波长一定的条件下,不同的界面波形排列不会直接影响系统TGO/BC界面波峰处的Mises峰值应力;由于幅值和波长变化有效地改变了TGO界面的曲率,它们是控制涂层双管系统TGO/BC界面应力分布的关键特征参量。

This research studied the stress distribution of a 700 ℃ novel coated steam dual pipe system under thermal-mechanical loading.By running the sequentially coupled simulation, it is shown that Mises stress distribution is strongly correlated with the TGO thickness and morphology, particularly that at the peaks of TGO/BC interface is more sensitive to the roughness. In addition, under the constant amplitude and wavelength of TGO, the maximum value of Mises stress at the peak of TGO/BC interface is directly determined by the local curvature of the interface rather than the arrangement of various waveforms. It is revealed that amplitude and wavelength of TGO are the crucial parameters controlling the stress distributed at the TGO/BC interface in the coated dual pipe system.