Stage Separation:
The ratio of the total molar rate of flow by the barrier inside a converter to the total rate of flow into the similar converter is known as the cut and is designated through the Greek letter Θ.
Θ = Molar flow of enriched stream/ Molar flow of input stream
Within a production cascade, a cut of around 0.5 is the optimum value along with respect to operating effectiveness and production.
Figure: "R" Stage Separation
The real separation achieved through a stage is expressed in words of the mol fraction of the light elements and for the reason of this discussion is designated through the capital letter R. It could be described as follows: if Y is the concentration of light elements within the enriched stream leaving a converter and X is its concentration within the depleted stream leaving the similar converter, then
R = (y/1-y)/(x/1-x)
This definition is same to in which of the separation factor, but, as display in above Figure, the value of R is based on the whole separation of a stage although that of the separation factor is based on the performance of the barrier alone. The relation among the two is given through the subsequent equation.
R = E α (1/Θ) h (1/1-Θ)
E is a correction factor known as the mixing competence. It could be explained as follows: because the light elements passes by the barrier more rapidly than the heavy elements, a layer of gas at the surface on the high pressure side of the barrier becomes more depleted within the light elements than the bulk of the gas on the high pressure side. Therefore, there is a focus gradient perpendicular to the surface of the barrier that output in a decrease in separation. Within the particular procedure of separation of uranium isotopes, a value of R within the preceding equation differs extremely little from unity (R = 1.003) and is somewhat inconvenient for use in calculations. Through subtracting 1 from every side of the equation, equating the symbol Ψ (psi) to R - 1, and through making a slight approximation, the equation becomes
Ψ = Y-X/X(1-X)
Given equation is used often in the plant in making separation tests.