It occurred to me that the whole reason folks find even newer cm designs "fiddly" is because the range of adjustment on the RC needle valve is quite literally a hairs bredth of a turn. Now you learn how to work this if you're running a cm and you're fine in the end but I feel like there has to be a way to make things a little less sensitive. My original cm condenser was an exterior coil with a few through condensers leading up to it. I thought I needed to make it counter flow so I fed the whole thing through the top. It was pretty touchy and only needed the top couple coils to be cold to really maintain a high reflux ratio. The vapor speed on my pathologically narrow column still wasn't enough to overpower this inefficient design at full flow so I was happy with it......until the annealed copper coil eventually sprang a leak. I built a new one, a tube and shell "west" condenser with a few through condensers inside it and fed it from the bottom. This one's about 4.75" in length and holds full reflux with all I throw at it, it's also touchy, maybe even more than my first design. It works, I can hit the same abv the old design did, counterflow be damned ( I speculate this design could be used to make PC's at a fraction of the recommended length but don't quote me on that.) . I feel now like maybe the trick to giving greater adjustment range and reducing control sensitivity may boil down to making a much less efficient condenser. The older cm designs use a few through tubes but I wonder if even that might be more than this design truly needs. Perhaps I misunderstand the principals involved here but i theorize that the cm needs more of a dephlegmator in the classic sense i.e. a partial condenser that can only achieve full reflux when the valve is open 100% without having to heat the water feed. So, first, correct my idea here if it's wrong please and then explain why in pornographic detail, the engineering fascinates me. My idea for an ideal cm dephlegmator might be something like 3 narrow through condensers spread further apart, perhaps a very narrow "west" style tube and shell or even more liebig proper that provides only a couple inches of actual cooling surface. You get the picture, something seriously under powered that can only just hold full reflux when completely open. This seems to make sense in my mind because I know both of my RC designs had way more oomph than is required to control take off meaning that anything above a slow trickle will throw the column into full reflux and even cool off the whole top of the column no problem.
Ok, there's my notion, cm condensers need to be less efficient: destroy it or support it. Ready, set, pick it apart!
Cm condensers are too efficient?
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Cm condensers are too efficient?
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