Abstract: The formula and solution procedure of characteristics based on incremental and non-incremental split scheme are given in this paper,and the Babuska-Brezzi condition of the two schemes is discussed.The convective acceleration term disappears along the characteristic.The momentum equation is solved by non-incremental split method,which satisfies the Babuska-Brezzi condition.Thus there is no restriction on the nature of the interpolation function.At last T3P3 element is used to solve incompressible N-S equation.The result shows that the characteristics based on non-incremental split scheme has good performance.
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