A gradient recovery method based on an oblique projection and boundary modification

Abstract

The gradient recovery method is a technique to improve the approximation of the gradient of a solution by using post-processing methods. We use an $L^2$-projection based on an oblique projection, where the trial and test spaces differ, for efficient numerical computation. We modify our oblique projection by applying the boundary modification method to obtain higher order approximation on the boundary patch. Numerical examples are presented to demonstrate the efficiency and optimality of the approach. References

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