modelEffectiveDiff

Information

This model might only be used for diluted systems, i.e. in both phases there is one component which has a mole fraction close to one.

In this case the interactions between the components can be neglected and the molar flow rate of a component i only equals the mole fraction gradient of this specific component:

The variables k (mass transfer coefficient) and A (interfacial area) have to be determined in the extending classes, since their determination is column-type dependent.

Modelica Definition

The code definition for the molar flow rates is as shown below. If the stage is still in start-up modus, by definition all incoming vapour will condense, and a mass transfer equation is only needed on the liquid side. If there is no start-up modus, there is also a mass transfer equation for the vapour side.

for j in 1:n loop

// Vapour side

if considerStartUp and startUp[j] then

for i in 1:nSV loop

Ndot_v_interface[j,i] = if j==1 then -Vdot_v_in*c_v_in[i] else -Vdot_v[j-1]*c_v[j-1,i];

end for;

else

for i in 1:nSV loop

end for;

end if;

// Liquid side

for i in 1:nSL loop

end for;

end for;

Parameters

Components

Contents