Vortex Tube

A low cost, reliable, maintenance free solution to a variety of industrial spot cooling problems. Using an ordinary supply of compressed air as a power source, vortex tubes create two streams of air, one hot and one cold, with no moving parts. Vortex tubes can produce:
• Temperatures from -50° to +260°F (-46° to +127°C)
• Flow rates from 1 to 150 SCFM (28 to 4,248 SLPM)
• Refrigeration up to 10,200 Btu/hr. (2,570 Kcal/hr.)
Temperatures, flows and cooling power are adjustable over a wide range using the control valve on the hot end exhaust.
EXAIR Vortex Tubes are constructed of stainless steel. The wear resistance of stainless steel, as well as its resistance to corrosion and oxidation, assures that EXAIR Vortex Tubes will provide years of reliable, maintenance-free operation.

A Model 3225 Vortex Tube keeps plastic dishwasher arms cool during ultrasonic welding.

Special high temperature vortex tubes keep a boroscope lens cool while inserted into a 1200°F (650°C) boiler porthole.

A pair of medium vortex tubes cool a solenoid coil after a welding operation.

• Cooling electronic controls
• Cooling machining operations
• Cooling CCTV cameras
• Setting hot melts
• Cooling soldered parts
• Cooling gas samples
• Electronic component cooling
• Cooling heat seals
• Cooling environmental chambers

• No moving parts
• No electricity or chemicals
• Small, lightweight
• Low cost
• Maintenance free
• Instant cold air
• Durable - stainless steel
• Adjustable temperature
• Interchangeable generators

Compressed air, normally 80-100 PSIG (5.5 - 6.9 BAR), is ejected tangentially (1) through a generator into the vortex spin chamber (2). At up to 1,000,000 RPM, this
air stream revolves toward the hot end (3) where some escapes through the control valve (4). The remaining air, still spinning, is forced back through the center of this outer vortex. The inner stream gives off kinetic energy in the form of heat to the outer stream and exits the vortex tube as cold air (5). The outer stream exits the opposite end as hot air (6). There is a detailed discussion of vortex tube history and theory later on page 180 in this section.

Cold airflow and temperature are easily controlled by adjusting the slotted valve in the hot air outlet. Opening the valve reduces the cold airflow and the cold air temperature. Closing the valve increases the cold airflow and the cold air temperature. The percentage of air directed to the cold outlet of the vortex tube is called the “cold fraction”. In most applications, a cold fraction of 80% produces a combination of cold flow rate and temperature drop that maximizesn refrigeration, or Btu/hr. (Kcal/hr.), output of a vortex tube. While low cold fractions (less than 50%) produce lowest temperatures, cold airflow volume is sacrificed to achieve them.
Most industrial applications, i.e., process cooling, part cooling, chamber cooling, require maximum refrigeration and utilize the 32XX series Vortex Tube. Certain “cryogenic” applications, i.e., cooling lab samples, circuit testing, are best served by the 34XX series Vortex Tube.
Setting a vortex tube is easy. Simply insert a thermometer in the cold air exhaust and set the temperature by adjusting the valve at the hot end. Maximum refrigeration (80% cold fraction) is achieved when cold air temperature is 50°F (28°C) below compressed air temperature.

32XX series Vortex Tubes optimize temperature drop and airflow to produce maximum cooling power or Btu/ hr. (Kcal/hr.). Specify 32XX series Vortex Tubes for most general cooling applications.

* SCFM (SLPM) at 100 PSIG (6.9 BAR) Inlet Pressure
** Btu/hr. (Kcal/hr.) Cooling Capacity at 100 PSIG (6.9 BAR)
*** Noise levels taken with hot and cold mufflers installed.

34XX series Vortex Tubes provide lowest cold air temperatures, but at low cold airflow (when less than a 50% cold fraction is used). Specify 34XX series Vortex Tubes only where temperatures below 0°F (-18°C) are desired.

* SCFM (SLPM) at 100 PSIG (6.9 BAR) Inlet Pressure
** Not Applicable. 34XX series Vortex Tubes are not normally used in air conditioning applications.
*** Noise levels taken with hot and cold mufflers installed.

The Vortex Tube Performance Charts below give approximate temperature drops (and rises) from inlet air temperature produced by a vortex tube set at each cold fraction. Assuming no fluctuation of inlet temperature or pressure, a vortex tube will reliably maintain temperature within ±1°F.

Numbers in shaded area give temperature drop of cold air, °F. Numbers in white area give temperature rise of hot air, °F.

Numbers in shaded area give temperature drop of cold air, °C. Numbers in white area give temperature rise of hot air, °C.

Other solenoid valves and thermostats available. Contact factory.
Note: Flow ratings shown (SCFM/SLPM) assume 100 PSIG (6.9 BAR) inlet pressure. At other pressures, flow is proportional to absolute inlet pressure.