  Goal oriented error estimation and adaptive procedures are essential for the
accurate and efficient evaluation of numerical simulations that involve complex
domains. By locally improving the approximation quality we can solve expensive
problems which could result intractable otherwise. Here, we present an error
estimation technique for enriched finite element approximations that is based
on an equilibrated recovery technique, which considers the stress intensity
factor as the quantity of interest. The locally equilibrated superconvergent
patch recovery is used to obtain enhanced stress fields for the primal and dual
problems defined to evaluate the error estimate.
