1. on Navier-Stokes preconditioning is due to C. L. Merkle and collaborators, whose papers date back as far as 1985 [28]. Typical of their approach is to write the preconditionedequationsintheform
2. . (34) For example, in a 1991 paper by Choi and Merkle [29],wefind
3. A different low-Re technique, contributed by Godfrey [17-19], is motivated by the discretized N-S equations. The idea is to combine an efficient Euler preconditioner, such as , with point-implicit or Jacobi relaxation. This type of relaxation may be regarded as an exact implicit solver for data that only contain the "checkerboard mode" (odd-even decoupling):itdampsthismode inonestep.
4. While Godfrey [17-19] tested this approach in explicit and numerical calculations, most analysis is due to D. Lee [5, 12]. He found that the matrix (40), with as the Euler preconditioner, does an excellent job in the domain