Vortex Tubes

There are three standard sizes for the basic Frigid-X® vortex tubes – the mini size which uses 2, 4 or 8 SCFM, the most common (medium) size which uses 10, 15, 25, 30 and 40 SCFM, and the large sizes which use 50, 75, 100 and 150 SCFM.  The large sizes are used in heavy industry but can cool to over 10,000 BTU/hr.  Vortex tubes normally come with the “hot end” adjustable to control the flow and temperature out the cold end.  The more flow out the hot side, the lower the temperature out the cold side.  It is important to note that the cooling effect (BTU/hr.) is determined by both flow and temperature drop.  So if cooling effect is important, then the flow out the cold end should be between 60% – 80%.  If the cold temperature is most important, then the flow out the cold end should be under 50%.

All vortex tubes have a “generator” which is sized for a certain flow.  There are basically two kinds of generators- one for cooling effect and then a second kind which limits the flow out the cold end, to achieve very low temperatures.   Depending on the temperature and pressure of the incoming compressed air, it is possible to achieve cold end temperatures as low as minus 40 and even minus 50 degrees F.

• Cool electronic and electrical control
• Cool machine operations/tooling
• Cool CCTV cameras
• Set hot melt adhesives
• Cool soldered parts
• Cool gas samples
• Cool heat seals
• Cooling environmental chambers

Our Stainless Steel vortex tube comes assembled with a brass generator as a standard item rather than cheap plastic for a longer lifespan and for applications in high-temperature environments. With virtually no moving parts, the vortex tube takes compressed air and converts it to cold air as low as minus 50° F (minus 46° C) at one end and hot air at the other up to 260° F (127° C).

For both the small and medium vortex tube you can easily convert the version that needs a screwdriver to the hand adjustable version, which ever is bets suited to the application.

Vortex tubes are most often purchase in the following packages:

• No moving parts, reliable, maintenance free
• No coolant
• Compact and lightweight
• Low cost application
• Maintenance free units
• Instant cold air in environmental chambers
• No spark or explosion hazard
• Interchangeable generators

How The Vortex Tube Work

Compressed air enters at point (A). Inside the vortex tube, the compressed air is made to spin using a “generator”. It travels in one direction along the small (hot end) tube and then back inside itself in the reverse direction creating one stream of air (B) and the second stream of air (C) in the opposite direction. The outside stream of air gets hot and exhausts at point (D). The center column of air gets cold and exists at point (E). Temperatures and capacities can vary by adjusting the hot end plug at (D) and by using different “generators”

Adjusting the slotted valve at the hot air outlet sets the flow rate and temperature at the cold end. The more air let out at the hot end reduces the cold air flowing and the cold air temperature at the cold end. Close the valve at the hot end and you increase the cold air flow at the cold end as well as the air temperature at the cold end. The percentage of total input air to the vortex tubes that is directed to the cold end is the “cold fraction”. A cold fraction of 60% to 80% produces the optimum refrigeration. See the chart below which indicates the temperature “rise” at the hot end and temperature “drop” at the cold end of a vortex tubes at various input pressures and “cold Fraction” setting.

Most industrial applications, such as electrical control panel cooling, parts cooling, tool cooling require maximum refrigeration and utilize the Frigid-X® 50000H series. Applications which require extreme cold temperatures such as lab sample cooling, circuit board testing, would utilize the Frigid-X®50000C series. However, mufflers are available for both the cold and hot ends if required.

Approximate temperature drops (and rises) from inlet air temperature produced by a vortex tube set at various cold fractions. Assume constant inlet pressure and temperature.

Approximate temperature drops (and rises) from inlet air temperature produced by a Vortex Tube set at various cold fractions. Assume constant inlet pressure and temperature. Tests were conducted with a 15H generator in a medium size Vortex Tube (Model 50015H). Will vary with other sizes and capacities