Particle Motion in Two-Dimensional Confined Turbulent Flows

This article introduces (1) the basic idea of a computer code on the basis of a Lagrangian model and (2) a method of computing particle concentration by the model. This computer program permits us to calculate the spatial distributions of particle velocity and concentration as well as the capture efficiency of the ventilation system in the two-dimensional confined turbulent flows. As a validation of the computer code, the experiment of Ruck and Makiola (1988), where the turbulent air flow passes a single-sided backward-facing step, is simulated. Then, we simulate a bounded turbulent field with a strong recirculation region to demonstrate the capability of the present program. The simulation is conducted for particles with diameters of 1, 60, and 100 μm and the predicted particle velocity and concentration distributions are given. The concentration of the 1-μm particles is also compared with that computed by the prediction program EOL (Fontaine et al., 1991).