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toka519
06-11-2016, 08:12 AM
I am currently building a small scale Einstein refrigerator prototype. My refrigerant is an ammonium hydroxide and sodium chromate solution (sodium chromate is being used as a rust inhibitor). I have been searching for any info about the volume or amount refrigerant used in such systems, and to no avail, have found nothing. So if anyone has any info about such things, any tips or ideas, it would be greatly appreciated...

xxargs
06-11-2016, 02:17 PM
Why Einstein process ??

Its suffer same problem as Stirling process - thermodynamic looks very temptation but very hard to build working unit and very few can done whole way and still have customer willing to pay the price...

Why difference in success between platen-munter and Einstein?

Platen-munters using ammonia as working cooling refrigerant but Einstein process using butan/isobutan as working cooling refrigerant (ammonium and water uses as 'pump' in Einstein-process, not for cooling) - this are whole difference between success and fiasco.


Why, if you look on heat of vapour, density and mass of refrigerant you see iso-butane need almost 3.5 times more volume/mass of refrigerant as ammonia for same cooling power, this need bigger pipes, bigger evaporator and condenser area etc. etc. for same cooling power as ammonia.

Einstein-process can be better than Platen-Munter if you build very big system, we talk industrial building size - but it size demand is fridge-size - forget it!

(is same situation in heat pipes for computer and laptops - it working pretty well with small amount of pure water and high vacuum inside pipe, but going complete mess if trying R134a as refrigerant depend of transporting mass needs be 10 time higher on gas flow and liquid transport in opposite direction inside pipe for same amount of transported heat and this stops up and stalled more and less inside pipe depend of gravity and capillary driven liquid transporting capacity to back to hot spot is very limited in this type of pipes)


This difference of heat of vapour between used refrigerant is whole different why platen-munter units builds in hundred of thousands units world wide over years, but Einstein-processes builds of none commercial company ie. Einstein-process needs very, very good heat exchange for larger mass/volume of refrigerant and pumping fluids in couple places in cooling-circurit if you want any cooling power left, but with Platen-munters circuit you can build more sloppy, cheaper, more simple and shorter heat exchanger and make smaller unit to cost of little lower COP and still have some cooling power left.

This are key factor to the market, they (Platen-Munter aka Electrolux later) make product had some usable cooling power left for cooling food to price people can afford to pay, compare to Einstein-process still is nice drawings on wikipedia and some papers written around it and published and most of them not thinking on size-factors is the key if make usable and efficient system or not depend of internal loss and unwanted heat transport is to high and wanted heat transport is to low in small system...

toka519
06-11-2016, 07:50 PM
ok, never mind, sorry for the bother. didn't understand a lot of what you said, but i get it.:confused: its a dumb idea to start with. i scrapped the whole thing.:( just for future sake, next time you answer a "newbie asks a question" you might want to dumb it down a whole lot. it feels a bit trollish and like it was dumb just to ask a question.

Magoo
07-11-2016, 01:32 AM
Hello toka519.
no such thing as a dumb question. Don't be put off at all. I have been asking dumb questions in industry for last 49 years, and still learning.

Grizzly
07-11-2016, 07:13 AM
Wise words Magoo.
Grizzly