A Soviet physicist, professor and doctor of engineering Yury Maydanik has considerably updated his loop heat pipes to be able to use them not only in space, where they have been successfully working since 1972. A pipe from stainless steel, filled with ammonia, in Yury Maydanik’s hands resembles the headphones cable. In the Soviet times the scientist supplied heat pipes to spacecraft builders. Now “Thercon-LHP”, founded by him in 2014, works with Russian and foreign producers of avionics, lasers, supercomputers and data-centres.
Thercon-LHP founded by Maydanik in his native Yekaterinburg, as planned by investors should reach the sales of 200 Mil rubles by the end of 2016. What has changed in the Soviet invention?
A Wick for Cold
Inside the sealed heat pipe there is a so-called wick: a net of thin pipes, "capillaries", and pores saturated with working fluid (which may be water, ethanol, or ammonia). Heat supplied to the one end of the heat pipe evaporates liquid inside the wick. The resultant vapor moves to the other end – the cooled one. Here it is condensed and absorbed into the "wick" again, which operates as a pump and returns the liquid into the evaporation area. Such a closed-loop system, where the liquid is pumped from one end to the other due to pressure differential, was invented in the 1960s by a group of American researchers headed by George Grover. Maydanik first heard of the heat pipes 10 years after the publication of Grover from his scientific advisor at the Urals Polytechnic Institute. Defense industry people asked the scientists to develop a universal pipe without Grover's drawback - the American invention only worked when the heat source was below the cooler.
In the Grover's circuit, pipes with liquid were located along the entire "wick" length. The uralians left them only in the heat supply area, reducing their number considerably. The diameter of "pores" in the wick did not exceed a micron (c.f.: the average thickness of a human hair is 50 microns) greatly increasing their "carrier effect". Now the "wick" could "transport" heat of at least one meter long in any position of the pipe in a gravity field. 'It just looked like science fiction,' recalls Maydanik. 'The whole department ran to us to watch how liquid goes up for inexplicable reasons. We ourselves could not believe that the circuit was working.' Three years later, when Maydanik defended his thesis on loop heat pipes, their samples were sent to the customer.
'The whole department ran to us to watch how liquid goes up for inexplicable reasons. We ourselves could not believe that the circuit was working.'
In 1980s, Maydanik already being the laboratory head of the Russian Academy of Sciences Ural Branch met with the head of the Krasnoyarsk Research and Production Association of Applied Mechanics engaged in space technology, who decided to test the invention. Soon, Lavochkin RPA joined their customers as well. Loop heat pipes made by the Maydanik group, were installed in space vehicles Granat and Gorizont, which were sent into space in 1989. Maydanik says that there are over 500 loop heat pipes on orbit now and none of them have failed.
Down to Earth
In the 2000s Maydanik realized that the invention could be adapted to new needs – for personal computers and industrial equipment. But to do that it was necessary to reduce them further in size, to figure out how to make them flexible. One of the important know-how's was a "wick" of diminished dimensions. Its diameter is now no larger than 2 to 8mm, it accounts for only a quarter of the heat transfer device weight, that is, depending on the design, 20 to 45 g, the total pipe length is 200 to 500 mm. It transfers the amount of heat comparable to one radiated by a bulb of 150 to 200W. And that occurs very quickly: after supplying heat to one end of the device the other one becomes hot in a second or even less.
Representatives of a Japanese corporation repeatedly offered him selling the technology; they said that he would not succeed in his homeland.
In 2002, the test samples were prepared and presented at an exhibition. Maydanik says that representatives of the Japanese Fujikura corporation, a cooling systems manufacturer, repeatedly offered him selling the technology, they said that he would not succeed in his homeland. 'And that stung me,' says Maydanik. 'I really wanted to launch production in Russia.'
He established the Thercon-LHP Corporation and was backed with 750,000 rubles from Bortnik Foundation to finalize prototypes of miniature loop heat pipes. A few years later, Maydanik met with Arkady Ivanov, an employee of Innovation Center for Small and Medium-Size Businesses of the Sverdlovsk Region. 'The scientist himself called me, invited me to the lab,' says Ivanov, who became executive director of Thercon-LHP. 'Usually, research teams are reluctant to meet the market.'
In 2014, the corporation received 45 Mil rubles from Leader Innovations Foundation, created with the participation of Russian Venture Company, Gazprombank and Sibur Holding. 'If we manage to launch the production of loop heat pipes at a cost comparable to other solutions, they will be very much in demand, and not only in Russia,' explains their interest Konstantin Nadenenko, the foundation managing partner. He estimates the world market of loop heat pipes as $1bn - if the technology gains up to 10% of thermal control systems market share, the total amount of which the BCC Research analysts estimate as much as $10.5bn at the end of 2015.
The first batch of miniature pipes was made by Thercon-LHP in March 2015. Laboratory of RAS Ural Branch, where Maydanik continues working and where most of his co-workers have come from, conducts new researches and licenses technologies of Thercon-LHP (the corporation itself is engaged in production only). For example, the laboratory has developed loop heat pipes with freon for avionics division of French Thales Group. Screen control units are connected to heat pipes under each seat along the frame - the devices save onboard passenger entertainment system from overheating.
Thercon-LHP revenue in 2015 was 40 million rubles.
'We doubted the ability of the project team, scientists and engineers of finding customers for mass batches of pipes,' says Nadenenko frankly. 'But it was quite soon when the company got the first commercial order, and that convinced us that there was a need to invest.' He speaks of the order from Tomsk Mikran Plant for radar equipment cooling systems. According to Mikran R&D manager Evgeny Mananko, the order was for a several thousand of pipes. Usually a high-powerful UHF equipment uses either liquid or air cooling systems. In the first case controlled check valves are required that have too few couplings and decouplings. In the second case it is difficult to "drag" air for an efficient heat transfer with minimum dimensions of the equipment. 'There are many more nuances,' Mananko explains. 'Hadn’t we use miniature loop heat pipes for our system but rather the standard solutions, it would have been 2 to 3 times more expensive and technically the design wouldn’t be optimal either.'
O2 Svetovye Sistemy, a Petersburg corporation, is testing LED lamps for sports lighting with loop pipes of the Ural plant. Conventional heat pipes were not suitable because of their size - a 250-500W lamp would be too heavy and large, as Sergey Feofanov, chief engineer of O2 Svetovye Sistemy, points out.
According to Ivanov, a data center in Europe is now testing some 40,000 loop heat pipes, which are a part of a cooling system for 20,000 servers; that will save up to 20% of power. A Russian manufacturer of UAV's, by using miniature pipes, wants to try and transfer heat to the gadget body – a drone CPU, battery and motor grow very hot, the heat accumulates inside of the sealed "box".
An average order for Thercon-LHP so far does not exceed 5,000 pipes. With such volumes, each product costs at least 10,000 to 12,000 rubles. If we can reach batches of hundreds of thousands ea., the price may be reduced to 700 - 800 rubles, as Ivanov promises. 'Tiny heat pipes will be in refrigerators for transporting vaccines and medicines, in solar panels of polar stations, not to mention heat pumps, hybrid transport and electric vehicles,' he dreams.
Now Thercon-LHP produces about 1,000 miniature pipes monthly, totaling 20 Mil rubles, but investors expect this year's outcome to increase the revenue five times. 'Professor MIT Lauren Graham noted recently that Russian scientists have a lot of powerful ideas, many of them have become a basis for inventions, now widely used,' says Maydanik. 'However our scientists have a prejudice: it is shameful to engage in business, revenue, profits – these are "unworthy" of a real scientist. But who said that science and business could not be combined? Engaged in applied science for many years, I finally see the results implemented in real products.'