A three-dimensional stochastic model for concentration fluctuation statistics in isotropic homogeneous turbulence
A three-dimensional model for prediction of concentration fluctuations in isotropic homogeneous turbulence is presented. The model is based on calculating the Lagrangian trajectories of a particle pair, taking into accout the interaction between the particle velocities. The velocity correlation function at a given instant is taken as the Eulerian one. This correlation function is constrained to obey the continuity condition, due to the fluid incompressibility. The proposed model was used to study concentration fluctuations for three different sources: A uniform sphere, a plane source and a line source. Results for the plane source differ from those predicted by the one-dimensional model. This difference may be attributed to the compressibility condition in the one- dimensional model [\textit{P. A. Durbin}, J. Fluid, Mech. 100, 279-302 (1980; Zbl 0457.76042)].
prediction of concentration fluctuations
scientific article; zbMATH DE number 4072599