Create a model for the system below, which is a $10ft10ft1ft$ "slice" of a cleanroom, that gives the

particle count in any $1f{t}^3$ unit in the volume $($all other slices in the room are numerically identical to this

so they can be ignored in this analysis$).$ Assume that air only flows sideways when it is forced to do so

by the equipment $($dark gray$)$ but ignore the effect of people on airflow. For recirculation purposes, all

the air in Zone $1($light gray$)$ is recirculated whereas the portion of air recirculated in Zone $2($light blue$)$

depends on the flow rate into this zone and the exhaust flow rate.

Test your model with the following "test case" input, which includes two people in the room:

If you have designed the model properly, for these inputs you should obtain the particle counts $($number

of particles in each $1ft$ 'volume shown to one decimal place for clarity$)$ shown below.

Calculate the particle count in each square in model #$2$ using the test case from #$1$ values.

Note that the number of particles penetrating the final filters in each column tor these input parameters

is around $\frac{2\mathrm{.}8}{m}in-$ your model should also give this value $($a more exact value is $2\mathrm{.}812844707,$ which is

much more precision than you would ever need but it will help you to determine if your model is

working!$).$ Since none of the counts in this volume exceeds $100$ particles $\frac{?}{f{t}^3}$ of $0\mathrm{.}5m$ diameter, this

could be a Class $100$ environment under Fed. Std$.209$E$.$

Create a place for your inputs

Calculate $G_C,R,R_F,G_T$ for each

zone separately!

Calculate total number of

particles entering the cleanroom

$($zone$)$ from all sources

Tidying$-$up$,$ we get the number per minute entering the region

$G_T[1+\frac{R_F}{1-R_F}]$

where

This number $-G_c=$ number of

particles$/$min entering the room through

the final filters $(\frac{28\mathrm{.}12844707}{10})$

Calculate the cumulative number of

particles per minute entering each

location