基于谱元法的热毛细流模拟及线性稳定性分析.docx基于谱元法的热毛细流模拟 及线性稳定性分析 重庆大学博士学位论文 学生姓名:尹林茂 指导教师:曾忠教授 专业:流体力学 学科门类:工学 重庆大学航空航天学院 二 O 一六年四月 Thermocapillary-Flow Simulation and Linear Stability Analysis based on Spectral Element Method A Thesis Submitted to Chongqing University in Partial Fulfillment of the Requirement for the Doctor’s Degree of Engineering By Linmao Yin Supervised by Prof. Zeng Zhong Specialty: Fluid Mechanics College of Aerospace Engineering of Chongqing University, Chongqing, China April, 2016 重庆大学博士学位论文 II 英文摘要 ABSTRACT The thermocapillary flow, driven by the non-uniform surface tension along free surface, appears often in industrial processing. Numerical simulation on thermocapillary flow, coupling with the dynamic deformation of free surface, is a long-term challenge in computational fluid dynamics. Meanwhile, the investigation on thermocapillary flow and its instability is important in many engineering application. In this paper, a Galerkin spectral element method (GSEM) and linear stability analysis based on GSEM were developed, and then thermocapillary flow and its instability were investigated. My main works are summaried briefly as: ① In accordance with the spectral approximation theory of the Fourier/Legendre orthogonal function systems, the Legendre-Legendre spectral element method and the Fourier-Legendre spectral element method for the Poisson-type equations were developed, then parison of putational accuracy between the two spectral element methods (SEM) was performed. ② In solving the unsteady Navier-Stokes equations, the time splitting method (TSM), including the classical time splitting method (CSM) and the normal time splitting method (NSM), is widely applied in literature. In this paper, an improved TSM, so-called the present time splitting method (PSM) was proposed. By modifying the pressure boundary condition, the proposed PSM is superior to CSM in accuracy and better than NSM in stability. ③ In solving the steady Navier-Stokes equat