In this paper, we consider mortar-type Crouzeix-Raviart element discretizations for second order elliptic problems with discontinuous coefficients. A preconditioner for the FETI-DP method is proposed. We prove that the condition number of the preconditioned operator is bounded by (1 + log(H/h))2, where H and h are mesh sizes. Finally, numerical tests are presented to verify the theoretical results.
- Crouzeix-Raviart element
- nonstandard mortar condition