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18.3.14 Postprocessing for Composition PDF Transport Calculations

Reporting Options

FLUENT provides several reporting options for composition PDF transport calculations. You can generate graphical plots or alphanumeric reports of the following items:

The instantaneous temperature in a cell is calculated as

 T_{\rm instant} = \frac{\sum_{i=1}^{N_c} T_p m_p}{ \sum_{i=1}^{N_c} m_p } (18.3-1)


$T_{\rm instant}$ = instantaneous cell temperature at the present iteration
$N_c$ = number of particles in the cell
$T_p$ = particle temperature
$m_p$ = particle mass

Mean and root-mean-square (RMS) temperatures are calculated in FLUENT by averaging instantaneous temperatures over a user-specified number of previous iterations (see Section  18.3.7).

Note that for steady-state simulations, instantaneous temperatures and species represent a Monte Carlo realization and are as such unphysical. Mean and RMS quantities are much more useful.

Particle Tracking Options

When you have enabled the composition PDF transport model, you can display the trajectories of the PDF particles using the Particle Tracks panel (Figure  18.3.5).

Display $\rightarrow$ Particle Tracks...

Figure 18.3.5: The Particle Tracks Panel for Tracking PDF Particles

Select the Track PDF Transport Particles option to enable PDF particle tracking. To speed up the plotting process, you can specify a value $n$ for Skip, which will plot only every $n$th particle. For details about setting other parameters in the Particle Tracks panel, see Section  22.16.1.

When you have finished setting parameters, click Display to display the particle trajectories in the graphics window.

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