Pointwise a Posteriori Error Estimates for the Stokes Equations in Polyhedral Domains
نویسندگان
چکیده
Abstract. We derive pointwise a posteriori residual-based error estimates for finite element solutions to the Stokes equations in polyhedral domains. The estimates relies on the regularity of the of Stokes equations and provide an upper bound for the pointwise error in the velocity field on polyhedral domains. Whereas the estimates provide upper bounds for the pointwise error in the gradient of the velocity field and the pressure only for a restricted class of polyhedral domains, convex polyhedral domains in R, and polyhedral domains with angles at edges < 3π/4 in R. In the cause of this study we also derive L a posteriori error estimates, generalizing well known L estimates.
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