Finite element methods for fractional PDEs in three dimensions

This paper is a generalization of the previous work (Yang et al., 2017) to the 3-D irregular convex domains. The analytical calculation formula of fractional derivatives of finite element basis functions is given and a path searching method is developed to find the integration paths corresponding to the Gaussian points. Moreover, a template matrix is introduced to speed up the procedures. Numerical experiments on a steady problem are presented verifying the efficiency of proposed techniques.