Use of the Palle, Nolan and Miller Correlation found in 2005 Physics of Fluid Article

The Correlation Takes the Basic Form

D(T,P) = f(Tr,Pr)*(Patm/P) *D(T,Patm)

Maple used to compute Diffusivities

Calculate the diffusivity of C2H4 and trace CO2

> restart

Calculate the Diffusivity at the given temperature and atmospheric pressure using the start301 program dcalc

> D12o := array ( 1…3, [1.1361e-5 * m^2/s , 1.3284e-5 * m^2/s, 1.5244e-5 *m^2/s]);

Also obtain critical temperature and critical pressure from start301.

> Pc1:=5066.3 kPa;Pc2:=7380.5 kPa; Tc1:=282.4 K;Tc2:=304.2 K; kPa:=1/100 bar;

Indicate mass fractions (if unknown, assume equimass)

>

Calculate the mean critical temperature and mean critical pressure

>

Indicate diffusion conditions (in bar and K)

>

>

Calculate reduced temperature and pressure

>

>

From here you calculate a correlating function f(Tr,Pr)

>

>

>

>

Calculate the diffusion coefficient at conditions

>

Plot using Matlab

>

>

>