This paper considers the mixed covolume method for the second-order elliptic equations over quadrilaterals.Superconvergence results are established in this paper on quadrilateral grids satisfying the h^2-parallelogram...This paper considers the mixed covolume method for the second-order elliptic equations over quadrilaterals.Superconvergence results are established in this paper on quadrilateral grids satisfying the h^2-parallelogram condition when the lowest-order Raviart-Thomas space is employed in the mixed covolume method.The authors prove O(h^2) accuracy between the approximate velocity or pressure and a suitable projection of the real velocity or pressure in the L^2 norm.Numerical experiments illustrating the theoretical results are provided.展开更多
We construct a new stabilized finite volume method on rectangular grids for the Stokes equations. The lowest equal-order conforming finite element pair （piecewise bilinear veloc- ities and pressures） and piecewise c...We construct a new stabilized finite volume method on rectangular grids for the Stokes equations. The lowest equal-order conforming finite element pair （piecewise bilinear veloc- ities and pressures） and piecewise constant test spaces for both the velocity and pressure are employed in this method. We show the stability of this method and prove first optimal rate of convergence for the velocity in the H1 norm and the pressure in the L2 norm. In addition, a second order optimal error estimate for the velocity in the L2 norm is derived. Numerical experiments illustrating the theoretical results are included.展开更多
We construct a finite volume element method based on the constrained nonconforming rotated Q_(1)-constant element(CNRQ_(1)-P_(0))for the Stokes problem.Two meshes are needed,which are the primal mesh and the dual mesh...We construct a finite volume element method based on the constrained nonconforming rotated Q_(1)-constant element(CNRQ_(1)-P_(0))for the Stokes problem.Two meshes are needed,which are the primal mesh and the dual mesh.We approximate the velocity by CNRQ_(1)elements and the pressure by piecewise constants.The errors for the velocity in the H^(1)norm and for the pressure in the L^(2)norm are O(h)and the error for the velocity in the L^(2)norm is O(h^(2)).Numerical experiments are presented to support our theoretical results.展开更多
基金supported by the '985' program of Jilin Universitythe National Natural Science Foundation of China under Grant No.10971082the NSAF of China under Grant No.11076014
文摘This paper considers the mixed covolume method for the second-order elliptic equations over quadrilaterals.Superconvergence results are established in this paper on quadrilateral grids satisfying the h^2-parallelogram condition when the lowest-order Raviart-Thomas space is employed in the mixed covolume method.The authors prove O(h^2) accuracy between the approximate velocity or pressure and a suitable projection of the real velocity or pressure in the L^2 norm.Numerical experiments illustrating the theoretical results are provided.
文摘We construct a new stabilized finite volume method on rectangular grids for the Stokes equations. The lowest equal-order conforming finite element pair （piecewise bilinear veloc- ities and pressures） and piecewise constant test spaces for both the velocity and pressure are employed in this method. We show the stability of this method and prove first optimal rate of convergence for the velocity in the H1 norm and the pressure in the L2 norm. In addition, a second order optimal error estimate for the velocity in the L2 norm is derived. Numerical experiments illustrating the theoretical results are included.
基金This work is supported by the “985”program of Jilin University and the National Natural Science Foundation of China(NO.10971082).
文摘We construct a finite volume element method based on the constrained nonconforming rotated Q_(1)-constant element(CNRQ_(1)-P_(0))for the Stokes problem.Two meshes are needed,which are the primal mesh and the dual mesh.We approximate the velocity by CNRQ_(1)elements and the pressure by piecewise constants.The errors for the velocity in the H^(1)norm and for the pressure in the L^(2)norm are O(h)and the error for the velocity in the L^(2)norm is O(h^(2)).Numerical experiments are presented to support our theoretical results.
