In this review, the fractals in the fractography is described, using brittle fracture surfaces of chromium and molybdenum, and stress corrosion cracking surfaces of SNCM 439 steel. It is emphasized that the quantitative fractography at the atomic region is opened, combining scanning tunneling microscopy with fractal geometry.

A technique is presented for computing multidimmsmnd time-dependent flow fields tiint avoids much of the inefficiency typically fouird in fiiiitc difference cnlculatious. Thc technique initially divides tho lluw field into regions. each containing B lneSll of gfnornl qusdrilateral chuson 10 provide spitiml resolution of the local features of tho flow. A Iinito difference operator of sccond order accuracy, consisting of n sequence of m edimensional operators (ench opcrating at near maximum Courant-Fricdrich-Lowy number) is then constructod for each region. Numerical resuits illuscrating the technique for inviscid flows abaut Simple bodies that gcncrate shock WBYOS. embedded shock waves, and expansion fans m e prcsenred and cumpircd wlth exact theory.

When the eddy viscosity is defined by the standard k-ε turbulence model, the equations governing self-similar incompressible plane and radial jets have a solution that is not analytic at the jet edge. A transformation that stretches the similarity variable simplifies the defining set of ordinary differential equations and makes them amenable to efficient numerical integration. Highly resolved solutions for the velocity, turbulent kinetic energy and dissipation rate profiles are tabulated and entrainment, velocity decay rate and growth rate are determined. The growth rate differs by 6 percent from a parabolic marching asymptotic solution to the full partial differential equations.

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