I am looking for an apparatus to cool/heat air without moving parts and using only a pressure source. From this, I came to a "vortex tube". However, all practical implementations are based on compressed gas used at the inlet tube.
Now my question is:
Would the "vortex tube" also work by applying an underpressure (using a vacuum pump) at one of the "outlets"? In addition, one of the "outlets" and the "inlet" would then be at athmospheric pressure.
The goal I would like to reach is to apply an underpressure at one side of an apparatus and thereby heating/cooling the air. Thermodynamically this should be possible since energy is put into the system via the applied underpressure, however I cannot think of any other apparatus other than the vortex tube.
Maybe there are other possibilities that I am unaware of? Thanks!
(Additional detail: an underpressure of 1 to 6 kPa is applied)