Least squares streamline di usion nite element approximations to singularly perturbed convection di usion problems
نویسندگان
چکیده
In this paper we introduce and study a least squares nite element approximation for singu larly perturbed convection di usion equations of second order By introducing the ux di usive plus convective as a new unknow the problem is written in a mixed form as a rst order system Further the ux is augmented by adding the lower order terms with a small parameter The new rst order system is approximated by the least squares nite element method using the minus one norm approach of Bramble Lazarov and Pasciak Further we estimate the error of the method and discuss its implementation and the numerical solution of some test problems
منابع مشابه
Least-squares Streamline Diiusion Nite Element Approximations to Singularly Perturbed Convection-diiusion Problems
In this paper we introduce and study a least-squares nite element approximation for singularly perturbed convection-diiusion equations of second order. By introducing the ux (diiusive plus convective) as a new unknow the problem is written in a mixed form as a rst order system. Further, the ux is augmented by adding the lower order terms with a small parameter. The new rst order system is appro...
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