For the fluctuation velocity
component u', the variance is calculated using
Turbulence fluctuation velocity enhances mixing and provides random dispersion of particles.
[[bar.u].sub.i], [u.sub.i], [u'.sub.i] = mean, instantaneous and fluctuation velocity vector of the fluid
The droplet motion is considered due to drag force of gas fluctuation velocity. For solving the equation of motion in most cases it is assumed that the initial velocity of droplets is zero.
In this case the droplet mixing is mostly affected by gas fluctuation velocity and the predicted values of droplet eddy diffusivity by Equation (14) are in good agreement with experimental data.
Where TI is the turbulence intensity, and it is defined as the ratio of the root-mean-square of the fluctuation velocity
, u', to the mean flow velocity, u