American scientists have used years of microgravity experiments to create a kind of “cold fire”: these are flames that reach a temperature of around 500 degrees Celsius, when traditional flames reach 1,700 degrees Celsius. The discovery could change the current understanding of fire and open up a new field of energy and technology applications.
According to a Press release from Washington University in St. Louis, one of the academic centers that participated in the research, so that the «new fire»To become a reality, it was essential to have the microgravity environment of space. Thus, the advances were made concrete and documented on board the International Space Station (ISS, according to its acronym in English).
The objective of the research is to understand the particular processes that take place in the spherical cold diffusion flames, with the idea of taking advantage of them for the design of new clean combustion engines. At a time in human history characterized by the eruption of environmental crises and energy problems, this application of cold flames could be especially useful.
In the space
These kinds of flames were observed for the first time also on the International Space Station, but in 2012: they appeared for a short time while a drop of fuel was burning. From there, together with the amazement of the researchers, they allowed the birth of a new field of study that seems to have no limits in the future.
The microgravedad it is experienced when the only force acting is gravity. At that moment, the affected body develops the phenomenon called “free fall”. Precisely, microgravity is what allows everything to float in space, in a scenario in which gravity exists but is minimal. The conditions of the ISS are ideal for experimentation in this field.
The “cold fire” is characterized by its faint, almost imperceptible flames. During experiments carried out on the International Space Station, the flames were so subtle that even the most sensitive camera that was available for the experiments could not register them.
How does the strange phenomenon occur? As the scientists explained, when the hot flame is extinguished and all related reactions are completed, the residual heat present in the burner ignites the fuel again. It is then that a cold diffusion flame can be seen, spherical and stable in shape.
Energy applications and in other fields
As reported by another Press release from the University of Maryland, cold flames have been created even in normal gravity conditions, using hot air and a mixture of liquid fuels and exotic oxidants. The normal or theoretical gravity it is an approximation of the real gravity on the surface of the Earth, obtained by means of a mathematical model that represents our planet.
Although the phenomenon itself has already generated great interest in the scientific community, the possibility of further technological development of cold flames adds more impact to the discovery. According to specialists, if a comprehensive understanding of the chemistry that makes the phenomenon of cold flames possible is achieved, it will be possible to create cleaner and more efficient burners and engines. At the same time, the researchers believe that the new technology may facilitate better fire safety.
It is possible to be optimistic about the use of cold flames, because they have several favorable characteristics that have never before been combined in a similar discovery. For example, the energy flows generated are known, controlled and stable, therefore there can be no surprises at that point.
At the same time, the cold flames are self-sufficient and have reaction zones with dimensions of around 6 millimeters, a magnitude that makes measurements and simulations easier. Will we be in the presence of a new power source What will be conventional and everyday in the future?
Photo: hot flames (left) give way to cold flames (right). Credit: University of Maryland / Peter Sunderland.
Eddie is an Australian news reporter with over 9 years in the industry and has published on Forbes and tech crunch.