On Mixed Finite Element Methods for First Order &lliftic Systems
نویسندگان
چکیده
A physically based duality theory for first order elliptic systems is shorn to be of central importance in connection with the Galerkin finite element solution of these systems. Using this theory in conjunction with a certain hypothesis concerning approximation spaces, optimal error estimates for Galerkin type approximations are demonstrated. An example of a grid which satisfies the hypothesis is given and numerical examples which illustrate the theory are provided. AMS(MOS): 65N30; CR5.17. The first author was supported in part by Army Research Office Grant DAAG 29-77-G-0026. The second author was supported in part by Air Force Office of Scientific Research Grant AF-AFOSR-80-0083. This paper was partially prepared as a result of work performed under NASA Contract No. NAS1-14101 and NAS1-15810 at the Institute for Computer Applications in Science and Engineering, NASA Langley Research Center, Hampton, VA 23665. This paper combines material presented previously in ICASE Reports and 78-7 with some new results. Pittsburgh, Pennsylvania 15213
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