Georges J. Ranque and the Vortex Tube

The Vortex Tube was invented by accident in 1928, by George Ranque, a French physics student. He was performing experiments on a vortex-type pump that he had developed for vacuuming iron filings and noticed that warm air exhausted from one end and cold air from the other when he inserted a cone at one end of the tube! Ranque quickly stopped work on the pump, and started a company to take advantage of the commercial possibilities for this odd little device that produced both hot and cold air, using only compressed air, with no moving parts. The company was not successful, and the vortex tube was forgotten until 1945 when Rudolph Hilsch, a German physicist, published a widely read paper on the device.

How A Vortex Tube Works

A vortex tube uses compressed air as a power source, has no moving parts, and produces hot air from one end and cold air from the other. The volume and temperature of the two air streams is adjustable with a valve built into the hot air exhaust.  Temperatures as low as -50°F (-46°C) and as high as 260°F (127°C) are possible.

During the second world war Georges J. Ranque started developing steels that would be used in military aviation efforts. After the war he took a job at  Aubert et Duval steelworks as director of metallurgical laboratory where he continued developing alloys for use in the aviation industry.

In 1972 he published a book on the search for the Philosophers stone, a legendary chemical substance capable of turning base metals such as mercury into gold. And in 1973 he passed away in his home just outside of Paris.

If you have any questions of want more information on how we use our vortex tubes to better processes all over industry. Give us a call, we have a team of application engineers  ready to answer your questions and recommend a solution for your applications.

Jordan Shouse
Application Engineer
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One Item Generates 1/4 Ton of Refrigeration and Fits in the Palm of your Hand

One of the most powerful, peculiar and perplexing products in the EXAIR catalog is the Vortex Tube. The medium sized vortex tube can generate up to a ¼ ton of refrigeration and still fit into the palm of your hand. It can generate cold temperatures that are 129° Fahrenheit below the input compressed air temperature, without any moving parts. It provides effective cooling on a wide variety of industrial systems like electrical cabinets, cutting tools, grinding operations, setting hot melt glue and a number of other cooling processes.

The Vortex Tube is used in Cabinet Cooler Systems, Cold Guns, Mini Coolers and Adjustable Spot Coolers to utilize compressed air to create cold air for your application needs. The Vortex Tube uses a Ranque-Hilsch tube to create the cooling effect. This principle has been used since 1927 to generate hot and cold flows from a source of compressed air. For more information on the physics behind how the Vortex Tube operates, visit here.

Our units are designed to operate at inlet pressures between 20-120 PSIG. The vortex tube comes in three different sizes, small, medium and large. The small unit will use between 2 and 8 SCFM of compressed air when fed with 100 PSIG of compressed air. It can be used with pressures much lower, but the change in temperature will not be as great. Below is a chart listing the temperature drops and rises of the vortex tubes with respect to supply pressure and cold fraction.

Vortex Tube Performance Data
The Cold Fraction performance chart shows temperature drops and rises for a Vortex Tube.

To use Vortex Tubes intelligently, cold fraction needs to be defined. A cold fraction is the ratio of cold air flow to total air flow through the inlet of the Vortex Tube. This cold fraction is adjustable on the Vortex Tubes and Adjustable Spot Coolers, but it is preset on the Cabinet Cooler Systems and Cold Guns. Adjusting the cold fraction changes 2 variables with the Vortex Tube. First, it changes the amount of cold flow from the Vortex Tube. Second, lowering the cold fraction also lowers the cold air temperature. Flow and temperature will both determine the heat transfer of the system.  For tool cooling operations, a very high cold fraction is used.  If you have a tool that may be operating above 150 or 200° Fahrenheit, it will cool faster with more air flow at a higher temperature than air at sub-zero temperatures. For applications where the final temperatures are very low, below freezing or sub zero, lower cold fractions can be used.

Find the blog next week to find out about what the addition of generators affects on a Vortex Tube.

Dave Woerner
Application Engineer
DaveWoerner@EXAIR.com
@EXAIR_DW