In this work, new finite difference schemes are presented for dealing with the upper-convected time derivative in the context of the generalized Lie derivative. The upper-convected time derivative, which is usually encountered in the constitutive equation of the popular viscoelastic models, is reformulated in order to obtain approximations of second-order in time for solving a simplified constitutive equation in one and two dimensions. The theoretical analysis of the truncation errors of the methods takes into account the linear and quadratic interpolation operators based on a Lagrangian framework. Numerical experiments illustrating the theoretical results for the model equation defined in one and two dimensions are included. Finally, the finite difference approximations of second-order in time are also applied for solving a two-dimensional Oldroyd-B constitutive equation subjected to a prescribed velocity field at different Weissenberg numbers.
翻译:在这项工作中,提出了新的有限差别办法,以处理在通用的Lie衍生物背景下的上流时间衍生物; 上流时间衍生物,通常在流行的粘结模型的构成方程式中遇到,为了及时获得第二顺序的近似值,以便从一个和两个方面解决简化的构成方程式; 对方法的脱轨错误的理论分析,考虑到以拉格朗格框架为基础的线性和二次间插操作者; 包括说明一个和两个方面定义的模型方程式理论结果的数值实验; 最后,对按不同韦森贝格数字指定速度场处理的二维奥德罗伊德-B构成方程式,也适用时间第二顺序的有限差近似值。