Optimal and near-optimal advection-diffusion finite-difference schemes 4. Spatial non-uniformity
نویسنده
چکیده
the non-uniformity can almost be removed with a local change of variables from c(s, t) to b(x, t). So, in numerical computations non-uniformity need not imply any reduction from optimal accuracy. A computational grid that was uniformly spaced with respect to s becomes non-uniform with respect to the intrinsic xcoordinate. Suitable non-uniform grid, optimal and near-optimal compact finitedifference schemes were derived in paper 2 of this sequence of papers. The cylindrical advection-diffusion equation is used as an exactly solvable test case.
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