Maqola

Aggregation of inertial particles in random flows

B. MehligDepartment of Physics, Göteborg University, 41296 Göteborg, SwedenMichael WilkinsonDepartment of Applied Mathematics, The Open University, Walton Hall, Milton Keynes, MK7 6AA, EnglandKevin DuncanDepartment of Applied Mathematics, The Open University, Walton Hall, Milton Keynes, MK7 6AA, EnglandThomas WeberDepartment of Physics, Göteborg University, 41296 Göteborg, SwedenMats LjunggrenDepartment of Physics, Göteborg University, 41296 Göteborg, Sweden

2005en

ABI

Annotatsiya

We consider the trajectories of particles suspended in a randomly moving fluid. If the Lyapunov exponent of these trajectories is negative, the paths of these particles coalesce, so that particles aggregate. Here we give a detailed account of a method [B. Mehlig and M. Wilkinson, Phys. Rev. Lett. 92, 250602 (2004)] for calculating this exponent: it is expressed as the expectation value of a random variable evolving under a stochastic differential equation. We analyze this equation in detail in the limit where the correlation time of the velocity field of the fluid is very short, such that the stochastic differential equation is a Langevin equation. We derive an asymptotic perturbation expansion of the Lyapunov exponent for particles suspended in three-dimensional flows in terms of a dimensionless measure of the inertia of the particles, epsilon, and a measure of the relative intensities of potential and solenoidal components of the velocity field, Gamma. We determine the phase diagram in the epsilon-Gamma plane.

Hali tarjima qilinmagan

Identifikatorlar

DOI: 10.1103/physreve.72.051104

Iqtiboslar va manbalar

2 ta iqtibos0 ta foydalanilgan manba

Koʻrsatkichlar — AkademScholar