Spectral element methods are well established in the field of wave propagation,in particular because they inherit the flexibility of finite element methods and have low numerical dispersion error.The latter is experim...Spectral element methods are well established in the field of wave propagation,in particular because they inherit the flexibility of finite element methods and have low numerical dispersion error.The latter is experimentally acknowledged,but has been theoretically shown only in limited cases,such as Cartesian meshes.It is well known that a finite element mesh can contain distorted elements that generate numerical errors for very large distortions.In the present work,we study the effect of element distortion on the numerical dispersion error and determine the distortion range in which an accurate solution is obtained for a given error tolerance.We also discuss a double-grid calculation of the spectral element matrices that preserves accuracy in deformed geometries.展开更多
基金funded in part by the SPICE-Marie Curie RTN project(contract MRTN-CT-2003-504267)supported by the ICTP Programme for Training and Research in Italian Laboratories,Trieste,Italy,and by CNPq,Brazil,under grant 314553/2009-6.
文摘Spectral element methods are well established in the field of wave propagation,in particular because they inherit the flexibility of finite element methods and have low numerical dispersion error.The latter is experimentally acknowledged,but has been theoretically shown only in limited cases,such as Cartesian meshes.It is well known that a finite element mesh can contain distorted elements that generate numerical errors for very large distortions.In the present work,we study the effect of element distortion on the numerical dispersion error and determine the distortion range in which an accurate solution is obtained for a given error tolerance.We also discuss a double-grid calculation of the spectral element matrices that preserves accuracy in deformed geometries.