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- The set of modular vortex tubes – new generation of simple, cheap and compact air coolers of 9-15 models (and modifications) for a range of cooling capacity from 0,02-0,15 kW up to 0,9-7,5 kW (70-500…3100-25600 BTUH).

- The set is based on two kinds of “vortex modules” only – BIG modular unit “104/102” completed with 4 or 2 vortex chambers and SMALL modular unit “052” completed with 2 vortex chambers. The product incorporates from 1 to 5 of simple “vortex modules” and from 2 to 20 of vortex chambers.

- Weight of the product is from 0,15 kg to 4,6 kg.
- Minimal used pressure of compressed air (from a factory or an onboard pneumatic-net) is 1,2-1,9 BARG (15-25 PSIG) and maximal pressure is 6,9 BARG(100 PSIG).
- Recommended “economical” pressure is 2,9-4,1 BARG (40-60 PSIG). The resulting temperature drops of cold flow is from 35oC to 52oC (63 … 97degF), if it is used “economical” pressure of compressed air dried to a dew-point -40oC (-40degF).


2, 5 – one-modular air coolers M104, M102 with rolling cold nozzle; 3 – two modular air cooler M104.2 with changeable number (2-10) of rolling cold nozzles; 4 – five-modular air cooler M104.5 with 5 ejectors on 5 cold nozzles for increase a body of air what ventilating the working area of personnel (for example, inside of tank on period when supertanker is under construction or modernization); 6, 7, 8, 9 – one-modular “dot” air coolers M052A,B,C,D: A – with adjustable speed of cold flow; B – with rotary cold nozzle; C – connected to object by flexible cold air line; D – with ejector for increase of cooling flow; 10 – two-modular cooler M052.2 (2 rotary cold nozzles).

FOR COMPARISON: 1 – the serially produced multi-purpose vortex air cooler В201 (with vortex chamber D=20mm). It is the base model of THE PREVIOUS GENERATION OF RUSSIAN VORTEX TUBES, 1983-2005 (Azarov’s Project 3 is incorporated 12 models of industrial vortex tubes). From 1983 three modifications of B201 (and others models ranked among these product) were manufactured by several enterprises of Russia and used on hundreds of factories: there are more than 800 of factories-users in total. For example, 44 factories-users are taken into account in Saint Petersburg, in Moscow – 48, Rostov-on-Don – 18, Nizhniy Novgorod – 18, etc.).


1 - Automatic lines. Robotized sections. No human processes. Programmable machines: Local or general cooling of the electronic control units.

2 - Painting shops. Metallurgical facilities. Shipbuilding. Glass and cement industry. Deep mines: Improving the atmosphere in working zones. Creating cool air curtains. Ventilation of dead ends of deep mines.

3 - Foundry with quick-setting moulds. Granaries and elevators***: Cooling of sand in a fluidized bed when preparing quick-setting mixtures. Cooling of granular materials…

4 - Furniture industry: Cooling of milling area when manufacturing face plates. Cooling of area of filling lacquer. Agriculture. Small ships...

5 - Self-propelled vehicles for the tropical countries (where the utilization of the freon air-conditioners for staff is prohibited). Medicine. Laboratories: “Spot” cooling of working areas for personnel. Agriculture. Small ships...

6 - Manufacture of polyethylene films, sheet rubber, sheet glass. Repair of technological furnaces: Blowing of cold air flow. Inertialess creation of “cold ”areas. Cooling heat-shielding suits.

7 - Bakeries. Sausage production lines. Candy-factories. Short-term storage of fruit and vegetables. Fruit transporting ships and trucks: Cooling of chambers and technological zones. 8 - Helicopters. Buses. Mining equipment. Combine harvesters. Tractors. Trucks. Diesel locomotives.: “Two-point” (“economize”) cooling of areas in cockpits. and 9,10,11…etс.



The vortex effect is a surprising discovery of the XX century: a “tornado” is obtained in a tube and its heat transfers “itself” from the axis to the periphery of the vortex flow. A simple refrigerating machine is a vortex tube (as a “point” source of cold and heat). It allows solving numerous technological problems during climatic tests of electronics and fuel equipment, during ground tests of aero-space equipment and others. First, hundreds of inventions directed at industrial and commercial use of the vortex effect appeared. Some of them will be a basis for advanced kinds of industrial products.

Let us name the three inventors, whose creative contribution (the “intellectual labour” of a developer) is already embodied in products produced serially during a few decades:
- G.J. Ranque invented the first vortex tube in the world (France, 1931);
- Charles Fulton suggested the simplest cylinder non-chilled vortex tube (USA, 1965) which still stays in production in the USA and Western Europe without any considerable changes;
- Anatoly Azarov has developed, patented, and organized a long-term serial production of a few generations of vortex tubes of different designs (USSR, Russia, 1968…2006), for example:
• miniature vortex tubes with D=4mm and 5mm for two generations of portable transport refrigerators (PROJECT 1);
• vortex tubes with an inner ribbing of a chilled vortex chamber, for test equipment (PROJECT 2);
• multi-chamber vortex tubes of multiple use with 2, 4, 6, 8, 16, and 20 flows of different temperature and many others (PROJECT 3).

Only four of Azarov’s projects developed for plants-producers are presented in the article. The publication’s aim is to show how, along with expansion of vortex tubes’ use, their constructional appearance changed and to present technology of the newest level: modular vortex tubes for the beginning of the XXI century (PROJECT 4). They open new opportunities for the producers and allow multiple uses for the users.

A.I. Azarov (b.1937) graduated from Nikolaev Shipbuilding Institute in 1960. Ph.D. (eng.), head of Laboratory of vortex technique (Author’s Laboratory) in St. Petersburg State Polytechnic University since 1983. Merited inventor of Latvia, corresponding member of St.Petersburg Engineering Academy, academician of Russian Academy of Natural Sciences. Author of more than 160 inventions and 140 publications in the field of industrial application of vortex effect and refrigeration, energetic and transport machinery.

A.I. Azarov
Saint Petersburg, Russia




The vortex tube (VT) is interesting for new energy and refrigerating engineering as an experimental object with high development potential and as industry product with a quickly widening, unique combination of technological and operation properties.


A jet of the compressed medium in the field of centrifugal forces “spontaneously” divides into a chilled nucleus and heated peripheral layers – transfer of heat from axis to periphery of a turbulent rotating flow is called the vortex effect. A cooling machine, which uses it, is a vortex tube (VT in Fig. 1). It is compact, has no wearable parts, inertialess and trouble-free during operation [1]. In the development of VT driving force is an experiment; according to its results, hypotheses are checked, different kinds of influence on vortex flow are compared, where:
• the radial pressure gradient 0.003-1.0 MPa/mm (up to 5 MPa/mm) with the vortex rotation frequency from 3x103 c -1 to 1x105 c -1 (the rotation frequency can be multiply increased in the experimental device for fundamental researches);
• distribution of speeds, pressures and temperatures according to the section and length of vortex chamber is
complicated (sometimes non-stationary) in the presence of secondary vortex flows and precession of the vortex flow nucleus;
• acoustic energy is generated and redistributed in the acoustically non-uniform environment: temperature, density, acoustic impedance of the moving medium differ by the section and length of the vortex chamber, which has the form of axisymmetric channel, and a level of acoustic pressure corresponds with the area of a non-linear acoustic, i.e. considerably exceeds 170 decibel;
• vorticity has anisotropic nature. In the paraxial area (to a half of the vortex flow radius) vorticity intensity is E=25-35% while, at the distance exceeding the radius’ half, the value of vorticity intensity decreases to E=5% and lower;
• a relative value of turbulent energy is maximal in the paraxial area and can reach 0.04-0.06 (which is considerably more than during non-swirled flow);
• in spectral characteristic of VT noise, there are “peculiarities”. Their interpretation (parts 3, 4) will lead to a deeper understanding of the vortex effect’s nature, show ways to increase VT efficiency;
• during operation using dry air, glow of the vortex’s nucleus and other “anomalies” are observed.

Fig. 1a. Formation of a tornado. A self-organizing process of transformation and concentration of energy diffused in different nonequilibriums (of temperature, moisture etc.).

Fig. 1b. VT design [2]: 1 – a hole d of the diaphragm for discharge of the cold vortex flow’s nucleus; d= (0.40–0.65)D; 2 – jet inlet; 3 – vortex energy division chamber; L= (3-25)D; 4 – throttle fordischarge of the hot flow (from 15% to 75% of air consumed by the adiabatic VT); a – trayrectilinear single-jet inlet of VT according to Fig. 2a; b – spiral inlet with the critical section Fc =(0.04-0.12)D2 and preliminary whirling of VT flow according to Fig. 3-8 and Fig. 2b; c and d – double-jet and multiple-jet tangential inlet of Vt, according to Fig. 2c.

According to the amount of registered and realized inventions in this field, Russia remains the leader. Transformation of VT from an experimental object into a product of multiple uses began almost simultaneously in the USSR and USA [3] in the 1960s.

For example, at that time, in the USSR:
• adiabatic VT for natural gas industry were tested and economical nonadiabatic VT with a chamber intensively chilled during air barbotage through liquid were prepared to long-term serial production (in Table №1 [2, 4, 5]), i.e. they are more perfect energetically than the adiabatic ones;
• growth of the “invention chain” began. These inventions defined the level of some following generations of VT showed in the Table by PROJECTS 1-4 (the USSR and Russian invention numeration: №№ 300726, 300727, 337621, 435419, 456118, 470684, 556285, 585376, 606044, 630964, 641245, 769233, 892146, 1255825, 2067266, 2177590);
• research and use of the invention group related to “pulse” intensification of the process in VT began (№№ 334449, 334450, 336473, 337620, 347435, 390337, 735877 and others).

(Note: VTs of foreign production presented today are almost similar (Fig. 2) to the simplest experimental models of the 1950s – 1960s. It seems paradoxical taking into account quickly changing generations of electronics, lasers, and rockets).

As a source of compressed air for the simplest VT, a pneumatic net of an enterprise is usually used. A cold flow with a temperature from +200C to -1200C and, occasionally, a hot one with a temperature from 400C to 1200C are obtained this way. In more complicated vortex devices, a flow of air, helium, oxygen, and natural gas could be chilled to cryogenic temperatures or heated by hundreds of degrees. VTs have been used during land tests of aerospace equipment [7], tests of electronics, fuel machinery, chemical and oil-gas engineering equipment. VT maintain necessary temperature locally (by points) in technological and/or working zones: during work near open flame, strong vibrations at a chilled object, dustiness, gassy environmental air, absence of a place for freon air-conditioners or impossibility of their maintenance. In such conditions, VTs are a simple and trouble-free tool of energy saving excluding the need for power-consuming total air conditioning in a large production area [8].




Fig. 2. Experimental and industrial VT of different years, compared:

a. 1950s [6]. Experimental adiabatic VT with two tray inlets, according to Fig. 1a.
b. 1960s [4]. Experimental nonadiabatic VT with a water cooling jacket on the chamber and a spiral inlet, according to Fig. 1b: D=5mm, L=30D (up) and L= 80D (down). Industrial variant of VT L=30D see in Table: p.№1 (1969 [2, 5]).
c. 2006. Present-time adiabatic VT of foreign production with the multiply-nozzle inlet, according to Fig. 1c, d.

We will show how, during change to multiple uses, the constructional and technological get-up of some generations of VT (made for many factories-users, not for single research-industrial experiments) has been changing and how the VT set-up will change soon. We will consider only four projects – stages of technology development. All of them are an initiative of one inventor-developer. No funds of the state budget or investors have been spent on their development.

The first project is a creative response to the need of transport mechanical engineering, which prepared diesel locomotives for export to countries with hot climate; the other two ones are responses to the need for “point” VT for engineering tools, mechanical engineering equipped with electronics; the fourth project is a qualitatively new technological level for the beginning of XXI century.

We will show VT made of metal and plastics, which work using compressed air: nonadiabatic VT with a chilled finned chamber; adiabatic (non-chilled) ones with minimal amount of parts and a heated diaphragm; portable vortex refrigerators for pneumo-provided transport objects. The newest technology oriented at minimization of expenses is presented by modular VT: there are from 2 to 20 interacting vortex chambers and from 1 to 5 multi-chamber “vortex modules” in them. The main results of the projects’ realization are expressed in the final chapter; characteristics of four generations of VT are presented in the Table.

The experience of innovation VT development has to be summarized taking into account a situation in science intensive kind of products on the internal and external markets. An attempt of such a summary is presented in the article.

For the first time in the world, nonadiabatic VT were used [2, 5] in the first generation of transport vortex refrigerators: since 1969, - on a model_production scale and, since 1971, - for serial production (Fig. 3). A temperature in a 14-liter refrigerator TVH-14 is from 0C to +70C with a temperature in a chamber, which is not provided with an air conditioner, is from 200C to 500C. The refrigerator became an additional consumer of compressed air from a board pneumo-system supplied by a “brake” compressor of the diesel locomotive, which is engaged cyclically. Connection of the refrigerator increased the relative “duration of engagement” of the PV compressor only by 0.5% (from 32.0% to 32.5%). This did not worsen the pneumo-system’s performance and allowed better use of the board compressor of high efficiency. With unessential expenses for the refrigerator, a level of comfort in the chamber and export price of the diesel locomotive increased.

(Note: The alternative decision to use absorption-diffusion refrigerators, called “Morozko”, gave no results: in the event of transport vibrations and a temperature in the chamber higher than 35C, these refrigerators do not work).






Fig. 3a-c. PROJECT 1.
Transport vortex refrigerators of the first generation:
a. TVH-14 in a cab of an export diesel locomotive 2TE114 (1969)
b. Design of a vortex refrigerating unit with a refrigerating accumulator (water, brine) in the refrigerator chamber: 1 – nonadiabatic VT D=5mm with barbotage cooling of the chamber (in Table №1); 2 – coil for preliminary cooling of compressed air before VT; 3 – channel of air-water mixture, cooling coil 2 and the VT chamber 1; 4 – ejector supplied by a hot flow from VT (15% of total air consumption by VT); 5 – liquid refrigerating accumulator with barbotage inlet of cold air from the VT 1.
c. Design of nonadiabatic VT with a U-shaped bent chamber and elements of the refrigerating unit for TVH-14 (positions are the same) c.

Fig. 3d-e. PROJECT 1.
Transport vortex refrigerators of the second generation:

d. TVH-15 with a refrigerating unit designed for conveyor assembling: VT D=4(6)mm (for TVH-50, TVH-15, TVH-5 – produced until 1991; see below and in Tables № 2-4) is located along an axis of a sectional counterflow heat exchanger for preliminary cooling of compressed air to +5C…+15C.
e. A miniature VT D=4mm with “non-frosting” diaphragm heated by the chamber heat: 1 – critical section; 2 – chamber; 3 – a hole of the diaphragm; 4 – diffuser of the cold flow made as a whole with the diaphragm.

A simplified adiabatic VT of the minimal size was used for the second generation of vortex refrigerators [9]. In order to decrease production costs, the amount of parts in this VT was decreased by some times: three outwardly similar modifications of VT differ only by an inner diameter of the vortex chamber and sizes of the spiral inlet (for refrigerators with capacities of 5, 15 and 50l; Fig. 3). The refrigerators have been produced for more than two decades and are used today because VTs are problem-free in operation [10].




Fig. 4. PROJECT 2. Vortex equipment for test departments and climatic chambers
a. a source of cold and hot flows containing an embedded VT D=20 mm (in Table: №5) – a “Working place of a
toolsetter-investigator of radio equipment RMNR-20T”, gold medal of the exhibition of USSR national economy achievements.
b. Two-stage 5-chambers VT D=10 mm with maximal temperature decrease of four “resulting” cold flows (in Table: №6).
c. Nonadiabatic two-chambers “laminar Azarov’s VT” D=38mm (in Table: №7) cut: 1 and 2 – ring gaskets and
plates-ribs; 3 – a spiral section of the helix; 4 – cold flow diffuser; 5 – the first cone section of the chamber.

Test departments and climatic chambers need a reliable and inertialess source of cold air with a temperature from 220K to 280K for casual testing of integrated products. Many plants used a decision, simple in use and cheap in production: compact adiabatic VTs with single-stage or double-stage expansion of compressed air or more economical nonadiabatic VTs of higher cooling efficiency. Prototypes of the VTs were preliminarily checked as tools of individual and collective heat protection of workers in energy engineering and metallurgy [11]. Designs of the VT have been presented to some industry fields for development of a test base (Fig. 4); the very first lots of VT were produced by the largest enterprises of engineering tools and the electronics industry in Leningrad (Saint Petersburg).

In order to initiate the appearance of competitive productions and selection of the best VTs under industrial conditions,12 models of the items for “running-in” in tool production, auto production, electronic industry and others were suggested: for air curtains at working places in hot departments; for cooling of solutions in galvanic baths; for “multi-point” cooling of program machines’ cabinets etc. The working designs, start marketing information, production prototypes, VT manuals [12] have been given for free to 60 plants (in response to hundreds of requests): metal and plastic VTs, fixed to a cooling object and embedded into it VTs, one-chamber and multi-chamber ones (Fig. 5, 6). It was expected that the plants will produce and use lots of the industrial prototypes of all 12 models themselves, for their own needs, and, then, the best prototypes will stay in production – these VTs, which will indicate industrial “preferences” and directions of further improvement. For example, in order to chill 17 control cabinets at a big automated line “Renault-2” for processing of 52 auto d. e. cylinder head models, during no-man production, which needs only problem-free electronics (see Part 2). Zavolzhsky motor plant used a lot of VTs, according to Fig. 5, at the left above. Users produced first thousands of VTs in dozens of cities: Vyborg, Vilnius, Ulan-Ude, Novosibirsk and others [13].

Then the main result was defined: from 6 to 9 plants became long-term suppliers of VTs (in Table: № 13, 15, 16, 18, 19, 20); for instance, in Rostov-on-Don, VT production was begun by competing plants in two industries – machine-tool building and auto-making (Fig. 5f,e). For the first time, embedded intensifiers of the vortex temperature division process were used [4, 5, 14]. Since competing suppliers appeared, users and producers began to prefer plastic VTs with one (Fig. 5) or a few (Fig. 6) vortex chambers to al-metal ones, i.e. industrial “preferences” have been defined.







Fig. 5. PROJECT 3. One-chamber all-metal and plastic VTs:
a. A simplest adiabatic VT D=20mm (in Table, №14). Below. A design project of the prototype № 31749 for the nonadiabatic “laminar Azarov’s VT”.
b, c. RVTK-16/1 device assembled with a fan (in Table, №13) - nonadiabatic “laminar Azarov’s VT” D=16mm of highest efficiency with cooling of the rib chamber and 100% share of the cold flow.
d. At an assembling department of RVTK 16/ 1: before assembling the fan to a jacket of the plate-rib chamber.
e. A design project of the prototype № 31750.
f. Industrial modifications of adiabatic VTs D=20mm of multiple uses used at hundreds plants from 1983-1993 (from left to right, in Table: № 16, 20, 17 and 15).

One and multi-chamber VTs began to compete with each other. Use of polymeric materials led to a new production level with attraction of highly effective equipment. Production costs decreased.

For example, at the High-energy Physics Institute (Protvino town of Moscow region) lots of two-chamber VTs (Fig. 6a) having the unique “flat” form and minimal overall size were used in main and badly accessible zones of big experimental devices for cooling extra-high-speed electronic blocks.
The competitive ability of the multi-chamber VTs have been confirmed by long-term practice and their further development is a task solved in PROJECT 4.




Fig. 6. PROJECT 3. Miniature multi-chamber VTs
without extensions embedded into powerful computer equipment
a. The simplest 2-chamber VT (D=10mm) with a “thickness” of 18 mm with minimal amount of parts supplied to
users in the same constructive get-up for more than 15 years (in Table: №18).
b. VT with drum arrangement of 6 vortex chambers (D=5 mm), with axial supply of compressed air and mufflers of cold and hot flows’ noise embedded into the ends of the drum (“MIkrofon” d42x100mm; in Table: №9).
c. 2-body VT (D=5mm) with individual temperature control of 16 cold flows, tubular flexible “cold” airways and a
flange for fixing in a cooling object (in Table, № 11).

According to incomplete data of only one industrial field (Ministry of electric industry) for 1990, the number of plants-users of VT of Project 3 exceeded 200: VTs became a “product for any plant”. In the end of 1990, Leningrad regional council and Council of Leningrad Polytechnic Institute nominated developer A.I. Azarov, awarding him the honorary title of an honoured inventor of the USSR.

By 2005, the number of plants-users increased by a few times. Many enterprises purchased lots of VTs many times. In order to define the main industries-users, hundreds of plants were considered: from 30% to 50% of the actual number of the VT users, according to PROJECT 3 [15]. For instance, in Saint Petersburg, 44 plants were taken into account; in Moscow – 48; both in Rostov-on-Don and in Nizhniy Novgorod – 18; in Yekaterinburg, Cheliabinsk, Samara – 5 plants in each city and so on. This amount of sampling was considered 100%.

The distribution of the plants is the following: 35% - engineering tools and electronic industry, chemical and oil-gas mechanical engineering; 18% - mining equipment, compressors and engineering of tools, bearing engineering, transport; 18% - shipbuilding, metallurgy, aluminum industry, hydraulic engineering, hydraulic machinery, plastic processing, polygraphy, glass production; 14% - aerospace industry, mechanical energy engineering, helicopter production, electric mechanical engineering; 15% - confectionary industry, bread-making plants and others.

First devices for point “non-machine” cooling using vortex or thermoelectric effect appeared almost at the same time, but the technology of thermoelectric (semiconductor) cooling developed quicker. In order to decrease development and production costs and save time, standard micro-modules with a relatively small amount of semiconductor elements are used for a lot long time. PROJECT 4 began to change to modular VT designs for the first time (Fig. 7 – 9). Material intensity of a product decreases by 2 times and more, if the one-chamber VT is changed to a module with 2 or 4 vortex chambers.

Aims of PROJECT 4. To abate costs using the simplest elements – modules with a decreased number of parts and labour-output ratio (comparing with VTs of the past). To suggest unified VTs with a different number of modules and chill production efficiency, properties and use. To present any patterns of a multi-modular VT, which would exclude a need for single projects for numerous new tasks, to producers and users. To give an impulse to expanding of use of the newest VTs.

Modular demands. It must be simple in production and have flow tracing with considerable noise clipping. The modules must be assembled in a complete product with a screwdriver.
For the first time, modular VTs were created (in Table: № 21-23) for a range of cooling productivity from dozens of Watts to 4.5-7.5 kW. They are based on two types of multi-chamber vortex modules: a small module «052»: dimension is d44x75 mm, two vortex chambers D=5 mm (Fig. 7, 8) and a big module «102/104»: dimension is d52x144 mm, 2 or 4 vortex chambers D=10 mm (Fig.7, 9).

With minimal production costs, users obtain from 10 to 14 models and modifications (Fig. 7):
• VT of universal use (in Table, № 21-25) - for long-term serial production. It began from the VT using the “small” and “big” modules (at the left, Fig. 8 and 9). “Natural selection” will define which VT modules will be preferred, as it happened during PROJECT 3 promotion.
• VTs of specialized use (in Table, № 26-30) – for production in small amounts as orders for them will be obtained.

Fig. 7. PROJECT 4. A new development stage of the technology:
A group of modular VTs of universal and specialized use (in Table: № 21-25 and 26-30), Using 1 or 2 modules «052», or 1, 2 or 5 modules «102/104».

An example for comparison: A number of parts, labour-output ratio, material intensity, mass and acoustic pressure of the modular VT M104, which has higher cooling productivity, are less by 3-4 times than the ones of three modifications of VT B201 of the PROJECT 3 working at hundred plants since 1983-1993 (in Table: № 15, 16 and 20; Fig. 5e, f).




Fig. 8. PROJECT 4. Miniature VTs with 1 or 2 two-chamber vortex modules «052»:
a. VT on the support (in Table, № 22 and 24): 1 – module «052»; 2 – vectorable nozzle of cold flow;
3 – temperature regulator; 4 – support; 5 – ejector capping.
b. VT with controlled outflow velocity of cold flow and bonding flange(in Table, № 21).
c. 2-modular VT with vectorable nozzlesof cold flow (in Table, № 26).




Fig. 9. PROJECT 4. VTs of universal use on the basis of module «102/104»:
a. VT during assembling (in Table: № 25).
b. The same, assembling is almost finished.
c. Wear capping of cold flow for module «102/104».


1. Development went from the one-chamber and multi-chamber VTs to the modular devices. VTs were used:
• first (PROJECT 1) – in transport and agricultural machine engineering: in refrigerators for the operator’s cab in export diesel locomotives 2TE 114, passenger diesel trains DR-1, DR-1A, DR-1P and in KamAZ cars, grain combines, tractors, buses;
• then (PROJECT 2) – in chemical and oil-gas machine engineering, radio electronics and tool engineering, motor industry: during temperature-climatic testing of new products;
• and, finally, (PROJECTS 3, 4) – in main industrial fields: for solution of production-technological problems of hundreds of plants-users.
2. Russian industry, as it is shown above, used several generations of VTs, not one generation (the one suggested by Fulton [3]) as foreign industry did. The construction get up of these several generations was determined by a single invention-developer – the article’s author.
3. Nonadiabatic VTs for “point” cooling of objects must be made more compact. It is necessary to change from VTs of D=38mm and D=16mm (Projects 2, 3) to the miniature VTs of D=2.5-10mm (experiments with VTs up to D=1mm).
4. Keeping a simple and trouble-free design, it is necessary to use only simple technological methods in VT development. Compact VTs with a minimal amount of parts and a quantity of vortex chambers, which is more than two [7, 8], are preferable. Russian plants have been using the advantages of multi-chamber VTs for more than 15 years (Fig. 6).
5. Instead of developing many future devices, the multi-chamber modules are suggested (Fig. 7 – 9) for different types of VTs. Multi-point cooling by some miniature VTs, according to the heat emission “topography” at the object is more efficient than total cooling of the object. This is why big production of constructionally perfect VTs with a cooling productivity of less than 0.2 – 0.4 kW has better economic prospects than production of VTs with a cooling productivity of more than 1 kW.
6. For many future applications, a change from “non-autonomous” VTs to autonomous ones which do not depend on the presence of a pneumo-net with an excessive resource near a chilled object. The processes of air compression, cooling and expansion are to be combined in a single “vortex block” along with high efficiency and compact size of a device. Creation of such a device is the most important inventive aim.

Table of technical characteristics
Vortex tubes of PROJECTS 1, 2, 3 and 4

• Allowed excessive pressure of compressed air at the VT’s inlet Pc = (0.1-1.0) MPascal;
recommended (working) pressure Pc = (0.2-0.7) MPascal; “economical” pressure Pc = (0.1-0.5)
MPascal. A temperature of cold flow out of VT is from 290K to 250-230 (220)K depending on the position of the VT operation mode regulator and compressed air pressure. * – under pressure of compressed air Pc = 2.5 MPascal at the inlet to two-stage VT. M is metal, P is polymeric material.
• Fields of use:
1 – mechanical engineering technologies, tools engineering, industrial electronics: creation of “cold zones” on the surface or in the volume of a tool and/or material; cooling of control units of program machines, automatic lines, robotized units, no-man productions;
2 – hot and noxious productions: air curtains in working zones of painting chambers, forges,
galvanic and metallurgy productions; deep mines: ventilation of dead-ends;
3 – foundry: cooling of sand in devices with quickly hardening mixtures: storage of agricultural products: cooling of grain and dispersed products in temporary storehouses:
4 – furniture industry: blowing of cold air in a milling zone during facing slab production and in a zone of lacquer loading in lacquer-loading machines;
5 - self-propelled equipment for hot climate: cooling of working zones in crane cabins, in drillers’ vans etc.;
6 – production of sheet materials: inflating of polyethylene film by cold flow; cooling of sheet rubber; glass production: inertialess creation of “cold zones”;
7 – transportation and storage of fruits and vegetables;
8 – food productions; transport, mining engineering;
9 – test devices;
10 – portable transport refrigerators, chillers of drinking water and many others.


For the first time in the USSR, the long-term serial production of miniature VTS is realized: nonadiabatic (D=5mm) and adiabatic (D=4 mm) ones. It is confirmed that VTs stably work without deterioration for more than 30 years using untreated and non-dried compressed air from the board pneumo-net. The successful use of VTs was an impulse to develop new Projects.

PROJECT 2: For the first time, adiabatic VTs with one-stage (D=20mm) and two-stage (D=10mm) expansion of compressed air are used for production testing. They effectively substituted ammonia refrigerating systems of foreign production. Nonadiabatic multi-chamber VTs of the new kind are used: with the rib chamber (D=38mm) in the form of a package of plates alternating with the ring gaskets.

PROJECT 3: Appearance of competing suppliers of VTs for hundreds of plants-users was initiated; the largest plants (GAZ, KamAZ) bought VT lots for many times. Statistically important information on VT users was obtained [15]: “point” cooling without use of the standard refrigeration equipment is used in many fields. In order to change to the new technological level (Project 4), the industrial “preferences” are defined.

PROJECT 4: The first in the world multi-chamber VTs are used by food industry plants. They have a better combination of properties and will take a leading position pressing the “classical” VT (part 2). Production of VTs using the “small” and “big” modules has begun. Along with the growth of a suppliers’ amount, a contest environment will be formed.

Note: VTs of single-purpose use were not considered in the article [7, 16-18].

AZAROV’S VORTEX TUBES: Technical characteristics

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Notes: Allowed excessive pressure of compressed air at the VT’s inlet Pc = (0.1-1.0) MPa; recommended (working) pressure Pc = (0.2-0.7) MPa; “economical” pressure Pc = (0.1-0.5) MPa.
A temperature of cold flow out of VT is from 290K to 250-230 (220)K depending on the position of the VT operation mode regulator and compressed air pressure. * – under pressure of compressed air Pc = 2.5 MPa at the inlet to two-stage VT. M is metal, P is polymeric material.

Fields of use:

1 – mechanical engineering technologies, tools engineering, industrial electronics: creation of “cold zones” on the surface or in the volume of a tool and/or material; cooling of control units of program machines, automatic lines, robotized units, no-man productions;
2 – hot and noxious productions: air curtains in working zones of painting chambers, forges, galvanic and metallurgy productions; deep mines: ventilation of dead-ends;
3 – foundry: cooling of sand in devices with quickly hardening mixtures: storage of agricultural products: cooling of grain and dispersed products in temporary storehouses;
4 – furniture industry: blowing of cold air in a milling zone during facing slab production and in a zone of lacquer loading in lacquer-loading machines;
5 - self-propelled equipment for hot climate: cooling of working zones in crane cabins, in drillers’ vans etc.;
6 – production of sheet materials: inflating of polyethylene film by cold flow; cooling of sheet rubber; glass production: inertialess creation of “cold zones”;
7 – transportation and storage of fruits and vegetables;
8 – food productions; transport, mining engineering;
9 – test devices;
10 – portable transport refrigerators, chillers of drinking water and many others.


Vortex tubes do not use greenhouse gases and can replace standard refrigerating equipment in well grounded cases: in cases when its use is impossible due to operational, dimensional, cost or ecological limitations. VTs are used in industry (see the Table in Part 1) but are not presented in the literature as devices of quickly widening use yet.

Meeting this lack, we will consider some examples of VTs use when:
• appearance of a “point” vortex cooling generator gives obvious advantages, which do not require additional basing, to a refrigerating system of an object;
• advantages of VT introduction into the refrigerating system are not obvious and it is necessary to compare competing technological solutions (for instance, in new application fields opened by development of the newest technological devices) to discover them.

First, we will introduce a simple method [8] of choice of a preferable refrigerating generator (among numerous available ones) based on a so called qualimetric evaluation of a technological solution [7,19].
It can be used at any stage:
• during development of a refrigerating system of an object taking into account specified operational conditions;
• during development of the industrial production;
• during processing of the long-tern use results.


Setting operational conditions and a field of use, it is necessary to quickly evaluate applicability or impropriety of VT (air chiller) in comparison with standard equipment for objects’ cooling. Choosing a preferable solution, the characteristics which are important for a producer and a user will be taken into account in their totality [7,8]. An objective choice is possible, according to a value of an “integral index of quality” K of a refrigerating system. In a general case, K is a ratio of a whole obtained result R to all costs S.

We will take that the whole result (R) for the air-cooling system (technological conditioning) is a used part of its
exergy cooling productivity and all costs (S) is a value of production and operational costs of the system. This approach allows showing an influence of the technological and operational factors on the result R and on the costs S (per year or a device’s life): discovering a dependency of the “integral index of quality” K’s value upon them. K’s dimensionality is kWhour/rouble (or kWhour/US dollar):


f(t) is a function of the reducing of the costs to a united time point; E is a normative coefficient of capital investments’ efficiency (E~0,2); t is VT’s life, years; A is a year time reserve; A = 8640 hours; b is a working time coefficient; h is a temperature dynamic coefficient, i.e. a part of working time without a time when a cooling system is reaching the operational temperature; a is an effective (actual) part of cooling productivity used for taking away heat from a product, a cooled object; Q is exergy cooling productivity of a cooling generator, a cooling system, an air conditioning system, kW; U is costs for the industrial production of a cooling system, roubles, US dollars; c is electric energy cost, roubles/kWhour (USD/kWxh); W is energy costs per pour, kW/hour; m is average error-free running time, hour; n is average loss of a cooling system’s working time per a repair, hour; p is a coefficient of the U costs’ increase due to repairs.

A cooling generator (refrigerating system) with the highest K is preferable for the specified conditions. Choosing the best refrigerating system, thus, a combination of the characteristics is used, not single characteristics of competing technological solutions. All important characteristics are included into this combination: the operational (a, b, m, n, t, h, Q, W…) and technological (U, p …) ones. The method was first used for basing, development and production mastering of the first serial vortex refrigerators and vortex tubes for them.
An example of choosing by the qualimetric evaluation method: let us change a vapor compression air conditioner to a vortex air cooler (VT) in a refrigerating system of a processor cabinet used under the environmental air temperature from 350C to 420C for a long time. If there is a pneumo-system with an excessive resource near the VT, such a change leads to an increase of the integral quality index of the refrigerating system by 1.2–2.9 times. Hence, the change is advisable under the mentioned conditions.


As a duty of the refrigerating system, VT supplements an embedded ventilation system and turns on automatically or manually, when overheat can occur in electronic control units under high temperatures of the environmental air (due to a lack of a regular ventilation heating of cabinets under high air temperatures). VT is used for this in different fields.
Let us consider some examples (Fig. 10, 11):



Fig. 10. A scheme of electronic cabinet cooling with VT(regular cabinet ventilators are not shown): 1 – a pneumo net of the plant, 2 – a collector- entrainment separator, 3 – an electric pneumatic valve («open-close»), 4 – a temperature sensor, 5 – B201, M102 - VT models; 6 – drainage of hot flow out of the shop’s, 7 – «cold perforated airways» in heat-intensive cabinet zones, 8 – chip cards – zones of local microclimate. Fig. 11. Industrial electronics cooling at food industry enterprises a, b - Vortex air cooler B201 (PROJECT 3) in a microprocessor cabinet of a big refrigerating device for a chamber of low temperature storage of semi-prepared foods. c - A vortex air cooling system of a microprocessor cabinet is introduced to a foreign guest.

Example 1. An automatic line “Renault-2” (210 equipment units united in a no-man technological chain for processing of 54 cylinder head models for automobile engines) was installed at Zavolzhsky Motor Plant. During the summer months, stoppages, spoilages, tool breakages began – time losses due to overheats in cabinets of the line’s electronic control. Summer indoor temperature exceeds 35-40C; there is no central conditioning system. Unstable operation of the automatic line during the hot season caused a threat of the year production plans’ wrecking in adjacent enterprises of the industry. In December 1984, television of Gorky city (and television of other regions) showed a film about production use of the invention group – “Azarov’s vortex tubes” for test equipment, transport refrigerators, heat protection equipment etc. The USSR Ministry of automobile production immediately sent a petition for emergency scientific and technological help to the plant, according to a community agreement. The same day, the developer gave representatives of the plant a VT prototype, its working drafts and a user instruction.

(Note: VT has been developed for heat-protection clothing used during repair of energy and metallurgy objects. They were use only in this field. Its availability for cooling of electronic control cabinets had to be defined but the emergency petition of the Ministry gave no time to search or develop an alternative solution).

ZMP produced first dozens of VTs (p.1, in Table: №14) for its needs (and need of other similar plants which faced the same problem of “summer” overheats of their electronics). In January 1985, 17 VTs were installed in all control cabinets of the line. Due to remoteness of the plant and emergency of the work, production and launching of the VTs in this case (unlike many others, see below) was carried out by the plant’s forces only, without help of the developer.

But it only made the result obtained by the plant, which knew about the industrial use of VT from the television film, more convincing: the line’s operation became stable, stoppages and spoilages caused by overheat of the electronics disappeared; annual capacity of “Renault-2” increased by 12.6% that was equal to additional operation of the line during 1.5 months a year. (There were no losses due to spoilage and change of chip cards). In this case, complete use of cold produced by VTs was practically 100%. The air conditioning system in a huge shop (with a square of 0.2 hectares) would have been more power-consuming by hundreds times and more expensive by thousands times, according to the amount of initial capital investments. In order to compensate the sum of all heat emissions in the shop (from electric motors, insolation etc.), cooling productivity of the air conditioning system must be hundreds times more than the one which 17 VTs can create for point cooling of the electronic units. Thus, VTs solve the problem of maintenance of a complicated technological system’s stable operation and, during hot periods, they act as a “multi-point” duty cooling system supplementing the regular cabinets’ ventilation cooling system.

Example 2. The use of VT consistently widens at baker and confectioner factories (in Table: № 15, 16, 20; Fig. 11) for cooling of processors which control factories’ compression refrigerating machines. Processor cabinets operate in rooms with high temperature, where a system of total air conditioning is unavailable due to energy and economical limitations. Specialists of these factories consider VTs as reliable and the most available solution of the problem of trouble-free electronics’ operation maintenance.

Example 3. A big automatic line for cardboard production made by specialists of the USA, Germany and the USSR in Leningrad region. Air moisture is up to 90% and process ammonia concentration is high in a shop. Due to the overheating of electronic control units, the line’s operation was unstable: regular compression air conditioners “Mesurex”, USA, (embedded into processor cabinets) stopped working. Heat failures of this complex technological system were impossible more than 15 years ago by a simple change of freon conditioners to the same amount of VTs (in Table: №13). The change has been carried out by the factory after getting consultation of the VT developer. The users expressed a desire to introduce VTs into the system of cabinets’ cooling as a main or additional tool for cooling of electronics at the following lines.

Example 4. Electronic control units at main production lines of KamAZ motor plant were supplemented by coolers (in Table: №19) and, in 2 months, 9 KamAZ plants stated their need for 3,162 vortex coolers.

Example 5. At a Moscow plant AZLK, in 1980s, some VTs were installed into processor cabinets of program machines (in Table: № 15, 16) in order to exclude overheating. According to the obtained result, the plant evaluated its need as a need for 3,000 VTs of this type (after modernization of the plant’s pneumo-net).

Example 6. An abstract from a letter of “Energomekhanichesky zavod” plant’s chief engineer, E. Turchin (№ 726 from 17.06.2003): “Vortex coolers BBP-20/1 are installed at posts of CNC machines and also at industrial electronic units “FANUK” (produced in Japan) and have been used continuously since 1995 to the present time providing for the necessary cooling of the mentioned objects. We have no claims concerning the use of the vortex coolers”.

The food industry is a large-scale user of different air coolers and heaters. The VT use continuously widens here for cooling of electronic control units (Fig. 10, 11). They are also directly used in food products production methods (Fig. 12 and 13).

Example 7. Blowing of cold air flow from a VT to the drum’s technological zone decreases duration of the icing application process (Fig. 12). This was practically confirmed by specialists of some Saint Petersburg and Moscow confectioneries.

Example 8. Caramel, which was preliminarily cooled on a production line (by a stationary cooling machine), is additionally cooled during hot seasons by VTs (Fig. 13). This makes it easier to divide caramel and improves the product’s quality.

Fig. 12. At confectioneries, VTs increase the process of icing application on nuts, raisins and other dispersed stuff in rotating drums by 3-4 times a. Drums at icing application shop. b. In order to cool a product locally, an operator inserts a VT (M102, M104) fixed on a turning post and connected to a source of compressed air – a factory’s pneumo net. There is a cone perforated flared end for cooling flow supply onto a product in the drum at the cold air outlet of the VT. Fig. 13. During hot summer, caramel is preliminarily cooled at the confectionery before its division: 1 and 5 – pneumo-net elements, 2 – a vortex cooler (M052V, M052C,M102,V201), 3 – a hot air flow tap, 4 – a jacket-airway with a notched outlet above the production line(after a “regular” refrigerating machine air cooler).

Example 9. In cabins of excavators at complex ore mines, a “pack” of VTs is used. They cool the operator’s working zone. At the same time, cabin pressurization preventing harmful complex ore dust into the cabin is carried out (Fig. 14). Examples considered above show that determinative criteria during the choosing of a cold air source are particular performance attributes of VT: compactness and inertialess operation (Fig. 10-13); a wide range of cold flow temperatures; an ability to create excessive pressure in a relatively close volume along with its cooling – the so called cabin pressurization (Fig. 14).

There are a lot of fields where VT can be used if only an oil-free compressor with a small reduction degree and the necessary efficiency is used for its supply (Fig. 15, 16). Advantages of the cooling system with VTs are not obvious: it is necessary to carry out an analysis taking into account the most important (or all) technological or performance characteristics, for example, on the basis of the method of qualimetric comparison of competing technological solutions, which has been shown in the beginning in the article. The VT use in cooling systems, according to Fig. 15 and 16, under experimental-industrial conditions, are not examined but their competitive ability mainly depends not only on VT but also on characteristics of other important cooling system elements: pos. 1-3 (Fig. 15) and pos. 1-4 (Fig. 16).

Fig. 14. In order to improve working conditions in cabins of power and pneumo provided excavators at complex ore mines, a unit from two or four VTs of BBP-20/1 model is used. They carry out cabin pressurization and air coolingheating in the working zone: a powerful excavator at Ust-Talovka mine. Fig. 15. “Multi-point” cooling of cabin 7 or cabin 8 of a self-powered object used under extreme temperature conditions (in deserts and other hot regions): 1, 2, 3 – a system of compressed air preparation, 4, 5 – VTs in the cabins (M052A, B, C, D or M102), 6 – routing of compressed air, 9 – hot air drainage.Fig. 16. Cooling of automobile fruit carrier’s chamber to +120C…+30C: 1, 2, 3, 4 – a diesel-generator, an electric compressor, a radiator, a compressed air dryer, 5 – hot air drainage, 6 – VTs of M102, M104, M102.2, or M104.2 models.

In these cases, introduction of VT into air cooling system of an object can be easily substantiated for especially stringent terms of the system use which condition:
• nonoperability of the “alternative” vapor compression refrigerating equipment under extremely high temperatures and vibrations at an object, for instance, when search teams work in deserts (Fig. 6);
• complete absence of maintenance of the vapor compression refrigerating equipment and impossibility to refill it by freon, for example, during episodic transfer of agricultural products by farmers from under-populated mountain regions to cities (Fig. 16).

Example 10.
We will consider only one VT use in the machine engineering technology [20] though different uses are available (Fig. 17). If a chamber for low-temperature influence on a material or a product is used rarely, it makes no sense to buy an expensive low-temperature cooling machine with exacting maintenance requirements. In this case, it is enough to use VTs assembled according to a scheme, which allows utilizing a part of cooling productivity which was not used directly in the low-temperature chamber.

Fig. 17. A regenerative-cascade scheme of the low-temperature chamber’s air cooling 10 for cold detail hardening rarely used in the machine engineering technology: 1, 2, 3, 4, 7 – a system of compressed air preparation; 5, 6 – VT models M102, V201 (first and second cascades); 8, 9 – counter flow recuperative heat-exchangers.Fig. 18. Cold air ventilation of tunnels and dead-ends in deep mines and also temporary store houses, in case there is no standard refrigerating equipment: 1 – VTs of model M102, M104, M104A, M102.2, M104.2, and M104.5; 2 – a mine’s (or store house’s) pneumo-net; 3 – hot air drainage.

According to a thoroughly discussed strategy of machine engineering development to 2010, tool engineering plays the leading role: development of its export oriented potential was planned; possibilities to increase program machines supply to India, Africa’s countries and other regions with hot climate and strict requirements to efficiency of cooling ventilation system for control micro-processors (and a “niche” for VT use during multi-point cooling of the most important cabinet zones) was evaluated. VT gives heat reliability to mechanical processing equipment with minimal costs, makes operation of a machine (line, unit) independent on the environmental temperature changes, and improves performance attributes of complex technological systems.

Vortex coolers, thus, would widen export possibilities of expensive equipment without raising its price. A cooling ventilation system supplemented by one or a few vortex micro-coolers in heat_ intensive zones of the processor cabinet is useful not only as an export product. Summer becomes hotter in a considerable part of Russia (while there are no air conditioning systems in most production shops). A need for micro-coolers for tool engineering (in the country and for export), according to the considered developments strategy, by a minimal evaluation, is about 20,000 items a year and it can greatly increase to 2010.

A big machine-tool plant or a supplier of micro-processor cabinets can be a producer: an enterprise with wide production connections in its field and established export connections. First lots of the modular VTs (M052A, B, C, D) can be used by the producer in its shops and then supplied by the producer to the users in adjusting fields. The following lots of VTs will be embedded into products; for example, into the micro-processor cabinets supplied to the users in the frame of the established production connections to Russia, Byelorussia, Kazakhstan, and Ukraine (all these countries have developed tool engineering). Then all models of the modular VTs of universal use will be used for widening export. At that time, the plants-producers will also have orders for the modular VTs of particular use.

Fig. 18 shows a possibility to use VTs for cooling of:
• agricultural products temporarily stored in boxes (when a specialized cooling equipment is absent but there is a pneumo-net around);
• dead-ends in mines and tunnels during drifting in hot regions;
• working zones of repairmen, welders, painters, during fitting-out of a ship; during works in tank ship’s tanks (where tank shell temperature can exceed 600C).

1. The Russian industry has long-term experience of successful VT use in different fields:
• in air curtains at fixed working places in metallurgy, galvanic and tanning industries, painting chambers;
• in electronic units cooling systems in control systems;
• during icing application onto confectionery products in drums and during caramel division (split);
• in portable transport refrigerators for a cabin;
• in chambers for temperature-climatic testing of products;
• in the furniture industry, during high-speed application of a glue strip and lacquer-loading machines’ operation;
• in cabins of a mountain combine; a self-powered object used under extreme conditions; a charging crane in metallurgy; an excavator;
• in shipbuilding and dockyards for improvement of working conditions in a small room;
• in rooms for short-term storage of agricultural products, in boxes and others.

2. With minimal time and costs, the use of VTs gives large-scale economical and ecological results. Reducing atmospheric emissions of greenhouse gases from the standard refrigerating equipment, it is necessary to consider VT as a device with high development potential which is not discovered yet. For example:
• multi-point vortex cooling of heat-intensive objects in well grounded cases makes it unnecessary to build an expensive central conditioning system at a plant;
• if an object needs local cooling for operation without maintenance under extremely high temperatures, vibrations, dustiness, gassiness, the use of VT has no alternatives because the standard refrigerating equipment is of little avail under these conditions.

3. I began the comprehensive experimental research of my first VTs (which were already industrially produced and used; see Part 1, PROJECT 1) guided by the first vortex technology specialists of the country: Professors V. Martynovsky and V. Alekseev [21, 22]. They and A. Merkulov [23, 24], vortex technology specialists of the first generation, created a scientific basis for us, researchers of the second generation. Thanks to this basis, both theory and practice of VT developed successfully. Today growth and modernization of the production economic sector would help accelerated promotion of miniature VTs. Production of the modular VTs will widen when Russian economics will be re-oriented from raw materials export to effective commercialization of the newest technologies.

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