Researchers from the Northumbria and Edinburgh Universities have devised a prototype mechanism that pertains to carbon fueled engines for Mars. Taking advantage of the physical phenomenon known as Leidenfrost effect, the envisioned engine would actually make use of the dry-ice deposits found on Mars, as opposed to making round trips to Earth for fueling. In other words, it is potentially a sustainable alternative to a conventional scope, and would be dependent on the native resources of the red planet – thus allowing for continued manned missions and even human activities (like colonization) on Mars’ surface.
Now, beyond the envisaged concept, the Leidenfrost effect in itself pertains to a scenario when a liquid is in contact with a hot surface that has a higher temperature than the liquid’s boiling point. This contact instantly transforms the ‘touching’ layer of the liquid into vapor – which in turn insulates the (still) liquid portion from the heat. For example, when water is dropped into a heated frying pan, the droplets canter around the surface – because of the layer of insulating vapor that allows them to levitate above the pan.
As for the prototype in question, the scientists used a circular block of dry ice above the heated aluminum surface – and the result pertained to the levitating of the block above the aluminum due to the aforementioned cushion of vapor due to Leidenfrost effect. However, the researchers did make one significant change to the experiment. Instead of having a plane surface, they modified the aluminum with circular ridges. This alteration of the surface directly affected the ‘floating’ motion of the dry ice by spinning it in a circular motion (as opposed to longitudinal motion), like a turbine.
The spinning motion in turn was utilized to produce alternating current, with the aid of a system of magnets and copper coils. In essence, the entire contraption acted as an electric motor that generated power from the Leidenfrost effect between the dry ice and heated aluminum. To that end, it should be duly noted – this is the first time in the history of mankind that Leidenfrost effect has been utilized to produce a credible form of energy. And even beyond innovation, this trick may very well play its practical part on the Mars surface – for both vehicular and human-oriented power needs. As Doctor Gary Wells from the Northumbria University makes it clear –
“The working principle of a Leidenfrost-based engine is quite distinct from steam-based heat engines; the high-pressure vapor layer creates freely rotating rotors whose energy is converted into power without the need of a bearing, thus conferring the new engine with low-friction properties.”
And lastly, another significant advantage of the envisaged scope is that the Leidenfrost effect is not actually dependent on the burning of fuel. Instead humans can use the abundance of carbon dioxide on Mars surface (as mapped by NASA’s Mars Reconnaissance Orbiter) , along with waste heat to create the electric motors – thus solving the woes of energy on an alien planet in a sustainable manner. As Dr Rodrigo Ledesma-Aguilar, a co-author of the research process, said in a succinct manner –
Carbon dioxide plays a similar role on Mars as water does on Earth. It is a widely available resource which undergoes cyclic phase changes under the natural Martian temperature variations. Perhaps future power stations on Mars will exploit such a resource to harvest energy as dry-ice blocks evaporate, or to channel the chemical energy extracted from other carbon-based sources, such as methane gas. One thing is certain; our future on other planets depends on our ability to adapt our knowledge to the constraints imposed by strange worlds, and to devise creative ways to exploit natural resources that do not naturally occur here on Earth.
Source: Northumbria University
Image Credit: Jonathan Sanderson/Northumbria University