The solar magnetic field is improved by properly combining a dipole and a hexapole to make the polarity at two solar poles opposite. The self-consistent steady state with two streamers, satisfying observation qualitatively, is obtained by long time interaction between the initial combined potential magnetic field and solar wind flow. Then the CME triggering model with concentrically circular closed magnetic field structure is taken to trigger CME between two streamers for research about CME propagating features near corona. The numerical result shows that the CME event is confined by the two streamers to propagate between them and the closed CME magnetic field structure is similar to that in the section of magnetic cloud, which can explain some features of magnetic cloud observed at 1 AU. Moreover, it is found that there exist some areas, where pressure and Lorentz force dominate flow, which could be helpful for analysis of CME event data observed at 1 AU.