THE CIARLET-RAVIART METHOD FOR BIHARMONIC PROBLEMS ON GENERAL POLYGONAL DOMAINS: MAPPING PROPERTIES AND PRECONDITIONING.

For biharmonic boundary value problems, the Ciarlet-Raviart mixed method is considered on polygonal domains without additional convexity assumptions. Mapping properties of the involved operators on the continuous as well as on the discrete level is studied. Based on this, efficient preconditioners are constructed and numerical experiments are shown. [ABSTRACT FROM AUTHOR]