CONDIF: A modified central-difference scheme for convective flows

摘要: For most practical purposes, the central-difference scheme (CDS) would be ideal only if it were unconditionally stable. It is a simple and second-order which easy to implement. does not introduce any ‘diffusion’ like truncation error. However, for grid Peclet numbers larger than 2, CDS leads over- under-shoots unstable. This paper presents method, called CONDIF, eliminates this undesirable feature of CDS. modifies by introducing controlled amount numerical diffusion based on local gradients. The can adjusted negligibly low problems. CONDIF has been used solve number test problems have widely comparative study schemes in published literature. all these CONDIF results are significantly more accurate those obtained from hybrid when very high (∞) flow at large angles (45 degrees) grid. In general computational effort comparable (within 20 per cent) that scheme. one instance rate convergence was found slower.