In order to improve the resolution of flowing structures simulated with the weighted essentially non-oscillatory(WENO)scheme
an improved WENO scheme(WENO-EX)is constructed. By considering the interaction among the smoothness indicators of sub-stencils and whole stencil
which is based on the classic WENO scheme(WENO-JS)proposed by Jiang and Shu
a term characterizing the smoothness of the whole stencil is introduced to constitute the new smoothness indicator which changes the assignment of the nonlinear weights. The theoretical analysis shows that the improved WENO scheme can keep the original design accuracy
and obtain smaller dissipation and higher resolution with larger nonlinear weight assignment to the discontinuous stencil. Subsequently
numerical simulations for the linear transport equation with different initial conditions and typical shock problems such as the double Mach reflection and shock-vortex interaction governed by the Euler equations are conducted with different WENO schemes
and the WENO-EX scheme achieves better numerical results. The results show that WENO-EX scheme has smaller error with the same grid in smooth regions
and higher resolution of flowing structures in dealing with problems containing discontinuities.
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