MadSci Network: Engineering |
Hilsch tubes
I have never used or seen one, but I have heard about them.
The device is commonly called the “Hilsch tube” and a Google search turned up over 200 hits (some duplicates). The two given below seemed appropriate and I think they will answer your question.
A discussion of the Hilsch-vortex tube: http://www.visi.com/~darus/hilsch/
A commercial product: http://www.exair.com/vortextube/vt_page.htm?source=google&group=vortextube
From your message it appears that all you plan to do is drop the pressure across the needle valve. That would give you a modest amount of cooling, but it will not approach the cooling you could get with a Hilsch-vortex tube.
Is there a reason you are using this technique rather than liquid nitrogen, dry ice, or a salt/ice or ethanol/ice bath? What temperature do you need?
They are occasionally used to provide spot cooling in plants, but seldom in a laboratory because they are very noisy.
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