Steve Papella's “magic” liquid: from NASA projects to liquid-cooled speakers
Among the inventions used in modern electro-acoustics, ferromagnetic fluid is of particular interest. Today on YouTube you can see a lot of beautiful tricks with its use, but that's not the point. The appearance of this fluid was directly related to the development of space technology.
Despite its origin, today this invention is used in quite earthly devices, ranging from hard drives to liquid computers and extremely peculiar clocks , which have already been written on the GT. Fluid is in demand in electronics, engineering, medicine, defense and many other areas. Under the cat, I will tell you how this invention appeared for space, how it is used in electro-acoustics, and what kind of controversy is being waged by audio lovers around its use.
Ferromagnetic fluid created an American scientist Steve Papell more than 50 years ago. At the time, Papell worked as an engineer at NASA and participated in the development of engines for spacecraft.
Steve Papell and Ferromagnetic Fluid
The developer faced a problem - you need to create a system that would force the fuel from the tank to move to the hole through which the pump pumps it into the combustion chamber. If we are talking about liquid fuel, then in conditions of weightlessness, the liquid freely levitates in the tank.
To solve the problem, the scientist decided to apply the original idea - to make the fuel magnetic, mixing it with some mass possessing magnetic properties. Thus, using external magnets, it will be easy to control the fuel in the tank.
A liquid substance was best suited to implement such a control mechanism. After several weeks of experiments, Papell presented the world with ferromagnetic fluid. To create his fluid, the scientist used iron oxide double magnetite (Fe 3 O 4 ), which he crushed by mixing oleic acid and then adding organic solvents.
Upon completion of the process, a colloidal suspension was obtained, which contained a suspension of magnetite particles with a size of 0.1-0.2 microns, in a ratio of 5% magnetite particles, 10% modifier, 75% solvent (for example, oil). Oleic acid molecules were used as a modifier that did not allow oxide particles to stick together.
The invention of the engineer was patented in 1965, US 3215572 A (Low viscosity magnetic fluid obtained by colloidal suspension of magnetic particles).
The invention of Papella was enthusiastically accepted by his colleagues in the scientific community and the space agency, which allowed his name to remain in the history of physics. However, despite the interest, NASA did not use his ideas, mainly because solid rocket fuel was preferred. Further experiments with ferromagnetic fluid in NASA dealt with spacecraft stabilization systems.
The fluid created by Papell is estimated as a very significant contribution - with this invention he laid the foundation for one of the new branches of physical knowledge - ferrohydrodynamics. Further development and introduction of ferromagnetic fluids into production practice were conducted under the guidance of NASA's colleague Papella, Ron Rosenzweig. The work was carried out in the AVCO corporation, which aimed to commercialize this invention.
Ron Rosenzweig and ferromagnetic fluid
It is difficult to say which company was the first to use ferromagnetic fluid for the production of speakers. The company SONY became the first mass manufacturer of sound emitters with ferromagnetic fluid, applying it to create RF drivers and broadband in 2012. Today, according to www.czferro.com , more than 300 million speakers per year are produced using ferrofluid.
The fluid is used to remove heat from the voice coil, and also acts as an additional damper that quenches parasitic resonances. In today's existing constructions, ferromagnetic fluid is held in the gap between the coil and the magnet due to the influence of the magnetic field, acting as a centering washer.
In the classic speaker design, the washer, which provides centering and damping of the voice coil, directly connects its (coil) with the diffuser. Studies at SONY have shown that traditional design introduces more distortion.
The fact is that the puck actually acts as a second diffuser and, accordingly, creates oscillations. Eliminating the puck nullifies its effect on sound reproduction. When using liquid, it is possible to reduce the distance between the coil and the diffuser, which allows minimizing the loss in the transmission of vibrations, making the speaker more flat and compact (while maintaining the same volume level).
Fluid provides a volume increase of 2 dB and reduces power consumption by 35%. Accordingly, the design increases the efficiency of the speaker, while providing additional damping. Fluid effects, which increase damping and reduce the resonances of such dynamics, were already investigated in the 21st century aip.scitation.org/doi/abs/10.1063/1.345854 .
The appearance of a new type of speakers is expected to provoke a reaction among people who are not indifferent to the audio equipment. As usual, discussions flared up, where the opinions of audiophiles, music lovers and other sympathizers were divided.
The traditionalists, having “tried” the innovation, noted the deterioration of dynamic (and especially “microdynamic”) characteristics. Critics especially often rest on the subjective sensations when listening and the authority of their expert experience in audio. Proponents of innovation noted a decrease in distortion, higher fidelity and high volume (given the size of the speakers), in the absence of objective data about what the liquid is bad.
It even went so far as some “bold experimenters” began to remove the liquid from the gap and talk about the fact that “the sound has become much better” (I was tired of commenting on such things, therefore, as a fact).
Someone also strenuously tried to cultivate the stereotype that fluid dynamics are installed only in budget equipment, which is also not true .
The masterpieces of logic on this topic from some “wise life experience” audio lovers of the sample of 2012 can be found here .
For my part, I want to warn those who want to remove the liquid from the speakers of their audio system, TV or laptop. Engineers manufacturers are not idiots, and if they wanted to use the design with the puck, they would have done it. I am not a big expert in “microdynamics”, but it is likely that any dynamic changes when using a liquid will be within the limits that can be neglected (if at all).
Ferromagnetic fluid is one of the most interesting inventions of the past century, the introduction of which is just beginning. Its use instead of a centering washer is one of the most noticeable and significant innovations in the production of dynamic emitters in the last 10 years. Perhaps the article will seem to someone to be one-sided, but I did not manage to find weighty arguments in favor of the fact that the liquid “harms the sound” or somehow spoils it. If such facts exist - share in the comments. But for now, in my opinion, this is exclusively good.
As a conclusion, I recommend viewing some amazingly beautiful rollers with ferrofluid.
Engaged visual effects and sculptures from ferromagnetic fluid:
Clock:
Images used:
www.czferro.com
www.sony.co.in
www.parts-express.com
www.hifinews.ru
www.samwha.com
Jeans
A wide range of high fidelity speaker systems is presented in our catalog .
Despite its origin, today this invention is used in quite earthly devices, ranging from hard drives to liquid computers and extremely peculiar clocks , which have already been written on the GT. Fluid is in demand in electronics, engineering, medicine, defense and many other areas. Under the cat, I will tell you how this invention appeared for space, how it is used in electro-acoustics, and what kind of controversy is being waged by audio lovers around its use.
History of creation and non-use
Ferromagnetic fluid created an American scientist Steve Papell more than 50 years ago. At the time, Papell worked as an engineer at NASA and participated in the development of engines for spacecraft.
Steve Papell and Ferromagnetic Fluid
The developer faced a problem - you need to create a system that would force the fuel from the tank to move to the hole through which the pump pumps it into the combustion chamber. If we are talking about liquid fuel, then in conditions of weightlessness, the liquid freely levitates in the tank.
To solve the problem, the scientist decided to apply the original idea - to make the fuel magnetic, mixing it with some mass possessing magnetic properties. Thus, using external magnets, it will be easy to control the fuel in the tank.
A liquid substance was best suited to implement such a control mechanism. After several weeks of experiments, Papell presented the world with ferromagnetic fluid. To create his fluid, the scientist used iron oxide double magnetite (Fe 3 O 4 ), which he crushed by mixing oleic acid and then adding organic solvents.
Upon completion of the process, a colloidal suspension was obtained, which contained a suspension of magnetite particles with a size of 0.1-0.2 microns, in a ratio of 5% magnetite particles, 10% modifier, 75% solvent (for example, oil). Oleic acid molecules were used as a modifier that did not allow oxide particles to stick together.
The invention of the engineer was patented in 1965, US 3215572 A (Low viscosity magnetic fluid obtained by colloidal suspension of magnetic particles).
The invention of Papella was enthusiastically accepted by his colleagues in the scientific community and the space agency, which allowed his name to remain in the history of physics. However, despite the interest, NASA did not use his ideas, mainly because solid rocket fuel was preferred. Further experiments with ferromagnetic fluid in NASA dealt with spacecraft stabilization systems.
The fluid created by Papell is estimated as a very significant contribution - with this invention he laid the foundation for one of the new branches of physical knowledge - ferrohydrodynamics. Further development and introduction of ferromagnetic fluids into production practice were conducted under the guidance of NASA's colleague Papella, Ron Rosenzweig. The work was carried out in the AVCO corporation, which aimed to commercialize this invention.
Ron Rosenzweig and ferromagnetic fluid
Fluid speakers
It is difficult to say which company was the first to use ferromagnetic fluid for the production of speakers. The company SONY became the first mass manufacturer of sound emitters with ferromagnetic fluid, applying it to create RF drivers and broadband in 2012. Today, according to www.czferro.com , more than 300 million speakers per year are produced using ferrofluid.
The fluid is used to remove heat from the voice coil, and also acts as an additional damper that quenches parasitic resonances. In today's existing constructions, ferromagnetic fluid is held in the gap between the coil and the magnet due to the influence of the magnetic field, acting as a centering washer.
In the classic speaker design, the washer, which provides centering and damping of the voice coil, directly connects its (coil) with the diffuser. Studies at SONY have shown that traditional design introduces more distortion.
The fact is that the puck actually acts as a second diffuser and, accordingly, creates oscillations. Eliminating the puck nullifies its effect on sound reproduction. When using liquid, it is possible to reduce the distance between the coil and the diffuser, which allows minimizing the loss in the transmission of vibrations, making the speaker more flat and compact (while maintaining the same volume level).
Fluid provides a volume increase of 2 dB and reduces power consumption by 35%. Accordingly, the design increases the efficiency of the speaker, while providing additional damping. Fluid effects, which increase damping and reduce the resonances of such dynamics, were already investigated in the 21st century aip.scitation.org/doi/abs/10.1063/1.345854 .
“Wet” vs. “dry”
The appearance of a new type of speakers is expected to provoke a reaction among people who are not indifferent to the audio equipment. As usual, discussions flared up, where the opinions of audiophiles, music lovers and other sympathizers were divided.
The traditionalists, having “tried” the innovation, noted the deterioration of dynamic (and especially “microdynamic”) characteristics. Critics especially often rest on the subjective sensations when listening and the authority of their expert experience in audio. Proponents of innovation noted a decrease in distortion, higher fidelity and high volume (given the size of the speakers), in the absence of objective data about what the liquid is bad.
It even went so far as some “bold experimenters” began to remove the liquid from the gap and talk about the fact that “the sound has become much better” (I was tired of commenting on such things, therefore, as a fact).
Someone also strenuously tried to cultivate the stereotype that fluid dynamics are installed only in budget equipment, which is also not true .
The masterpieces of logic on this topic from some “wise life experience” audio lovers of the sample of 2012 can be found here .
For my part, I want to warn those who want to remove the liquid from the speakers of their audio system, TV or laptop. Engineers manufacturers are not idiots, and if they wanted to use the design with the puck, they would have done it. I am not a big expert in “microdynamics”, but it is likely that any dynamic changes when using a liquid will be within the limits that can be neglected (if at all).
Total
Ferromagnetic fluid is one of the most interesting inventions of the past century, the introduction of which is just beginning. Its use instead of a centering washer is one of the most noticeable and significant innovations in the production of dynamic emitters in the last 10 years. Perhaps the article will seem to someone to be one-sided, but I did not manage to find weighty arguments in favor of the fact that the liquid “harms the sound” or somehow spoils it. If such facts exist - share in the comments. But for now, in my opinion, this is exclusively good.
As a conclusion, I recommend viewing some amazingly beautiful rollers with ferrofluid.
Engaged visual effects and sculptures from ferromagnetic fluid:
Clock:
Images used:
www.czferro.com
www.sony.co.in
www.parts-express.com
www.hifinews.ru
www.samwha.com
Jeans
A wide range of high fidelity speaker systems is presented in our catalog .
Source: https://habr.com/ru/post/410421/