I see your point about the saturation gradient influencing evaporation, and while I understand that it could contribute to the performance in a vacuum centrifuge, I’m curious about the extent of its impact. Given that the primary goal of the g-force is to minimize foaming during aggressive boiling, I wonder if the saturation levels play a significant role in the overall evaporation rate. It seems to me that the design focus was more about optimizing boiling without introducing foaming issues.
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I believe you are correct about the design principle and its purposes @De_Neil , and I’m glad you understand what I am saying. Like you, I am unsure what the precise impact on any given solution’s evaporation rate might be, but I suspect it varies according to the propensity of the solution to “skin” (and, ofc, the continuously shifting concentration across the whole solution volume). Skinning is actually what causes foam to form on the surface of a boiling solution, and naturally this foaming (and eventually hardening of dried solutes) increases along with the concentration of solutes, as the solution evaporates.
This note about the rocket concentrater you included implies more than just “preventing any bumping” as stated. It also nods to the immediate forced sinking of any dried solutes from the surface (the skinning & foam forming stuff), because any skin or film of solute formed on the liquid surface would otherwise halt the evaporative escape of molecules from that surface. The only way to keep a solution with a lot of film forming solutes evaporating is to disrupt that supernatant film formation. This is usually accomplished simply by stirring the solution while heating it (assuming the convective flow by heating is insufficient stirring on its own).
However, by using enhanced gravity to pull the solids down to the bottom of the boiling vessel (instead of just redistributing them with stirring), one accomplishes some especially effective conditions to speed up evaporation:
A. Skin/film/bubbling/foam is eliminated from the surface, continuously opening it up to freely vaporize. (stirring does this, too, ofc)
B. Solids on bottom act as nucleation sites for gas bubbles (ala “boiling chips”).
C. The highest concentration of solutes (which raise a solution’s boiling point) is kept on bottom, i.e., opposite and as far away as possible from the vaporizing surface… so the lowest boiling point liquid is right at the surface!
Do you see how, in this way, it is like “squeezing the gas out of the sponge”? I apologize if my oversimplification caused any confusion, but this is what I meant. 
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