Superconvergence of a New Nonconforming Mixed Finite Element Scheme for Elliptic Problem

Table 4

Superconvergence results of 𝜓 and 𝑢.

𝑁	‖𝜓−𝐽2ℎ𝜓ℎ‖0	Rate	‖𝑢−𝐼2ℎ𝑢ℎ‖ℎ	Rate
8^2	0.07704230005041	/	0.06805851358971	/
16^2	0.01905713318621	2.01531966736879	0.01670893020781	2.02615627537278
32^2	0.00474917374465	2.00458266513090	0.00415565843089	2.00747038382646
64^2	0.00118603209709	2.00153348351974	0.00103721683378	2.00235955252584
128^2	2.964169140807930𝑒−004	2.00044337559203	2.591844848686839𝑒−004	2.00066626183030
256^2	7.409813186219603𝑒−005	2.00011869741141	6.478819154402888𝑒−005	2.00017656612731