If a rigid plate is subjected to stress and attached to a soft elastic medium, it is very likely that this stress is relieved by wrinkling: The plate buckles into a large number of waves. First the basic equation for wrinkling is rederived. Then the more complicated case of isotropic wrinkling...

Drag reduction is investigated in one- and two-dimensional turbulent flows that are stationary and homogeneous. In the two-dimensional case, the polymer chains are deformed though advected passively through the Kraichnan cascades within a scaling analysis. The typical rate of shear must then be...

The macroscopic properties of fractured porous media locally governed by a Laplace equation are determined by several methods. The first one consists in discretizing the porous medium and the fractures and in solving the Laplace equation in the discretized structure. The other methods consist in...

We present a simple model which describes elastic response of single-stranded DNA (ssDNA) to stretching, including the regime of very high force (up to 1000pN). ssDNA is modelled as a discrete persistent chain, whose ground state is a zigzag rather than a straight line configuration. This mimics...

In an earlier paper, Ngan (Phys. Rev. E 68 (2003) 011301) proposed a statistical mechanics-based theory to predict the mathematical form of the probability force distribution of contact forces in stressed granular packings. However, the wrong choice of the mean-force constraint in that work...