Gradient Recovery for the Crouzeix-Raviart Element
نویسندگان
چکیده
A gradient recovery method for the Crouzeix–Raviart element is proposed and analyzed. The proposed method is based on local discrete least square fittings. It is proven to preserve quadratic polynomials and be a bounded linear operator. Numerical examples indicate that it can produce a superconvergent gradient approximation for both elliptic equations and Stokes equations. In addition, it provides an asymptotically exact posteriori error estimators for the Crouzeix–Raviart element.
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ورودعنوان ژورنال:
- J. Sci. Comput.
دوره 64 شماره
صفحات -
تاریخ انتشار 2015