DIFFERENCE-QUOTIENT TURBULENCE MODEL - A GENERALIZATION OF PRANDT MIXING-LENGTH THEORY

A difference mean-velocity turbulence model to calculate quasistationa ry fully developed turbulent motion is presented. It takes account of the various eddy sizes in turbulent flows. As a consequence, some gaps between semiempirical closure models and sophisticated theories, desc ribing eddy energy cascades, are reduced. In a first-order expansion, the model is identical to Prandtl's mixing-length theory, which is sti ll contained in modern numerical computation schemes, e.g., k-epsilon models.