摘要

The dispersion of a passive plume released from a concentrated line source into a homogeneous isotropic turbulent flow is studied using direct numerical simulation. The focus of this study is on the turbulent convective regime of plume development. The characteristics of the plume in this regime of development are exhibited using the properties related to the growth of the mean plume width and the behavior of the concentration variance. Furthermore, the nature of the concentration fluctuations in this regime will be investigated in terms of the probability density function of concentration, the concentration power spectrum, and the balance of budget terms in the transport equation for the concentration variance.