Concentration fluctuations in two-dimensional turbulence

B. Krane; H. L. Pécseli; J. Trulsen

doi:doi:10.1209/epl/i1996-00193-6

Concentration fluctuations in two-dimensional turbulence DOI: 10.1209/epl/i1996-00193-6

Europhys. Lett, 36 (2), pp. 99-104 (1996)

Concentration fluctuations in two-dimensional turbulence

B. Krane , H. L. Pécseli and J. Trulsen

University of Oslo, Institute of Physics - Box 1048 Blindern, N-0316 Oslo, Norway
University of Oslo, Institute of Theoretical Astrophysics, Box 1029 Blindern, N-0315 Oslo, Norway

(received 28 March 1996; accepted in final form 29 August 1996)

PACS. 47.27Qb - Turbulent diffusion.
PACS. 92.60Sz - Air quality and air pollution.
PACS. 02.60Cb - Numerical simulation; solution of equations.

Abstract:

The dispersion of a cloud of passive test particles in homogeneous and isotropic two-dimensional turbulence is studied by direct numerical simulation. The basic statistical properties of the concentration of the cloud are analyzed with particular attention to space-time variations in the center-of-mass frame. Approximate analytical expressions for the concentration and the concentration fluctuations can be obtained from the power spectrum of the velocity fluctuations.