Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Spiky ferrofluid thrusters can move satellites

12.07.2017

Brandon Jackson, a doctoral candidate in mechanical engineering at Michigan Technological University, has created a new computational model of an electrospray thruster using ionic liquid ferrofluid -- a promising technology for propelling small satellites through space. Specifically, Jackson looks at simulating the electrospray startup dynamics; in other words, what gives the ferrofluid its characteristic spikes.

He is the lead author of a recent article in Physics of Fluids, "Ionic Liquid Ferrofluid Interface Deformation and Spray Onset Under Electric and Magnetic Stresses".


A ferrofluid is a magnetic liquid that turns spiky in a magnetic field. Add an electric field and each needle-like spike emits a jet of ions, which could solve micropropulsion for nanosatellites in space.

Credit: Sarah Bird/Michigan Tech

More than 1,300 active satellites orbit the Earth. Some are the size of a school bus, and others are far smaller, the size of a shoebox or a smart phone.

Small satellites can now perform the missions of much larger and more expensive spacecraft, due to advances in satellite computational and communications systems. However, the tiny vehicles still need a more efficient way to maneuver in space.

Scaled-down plasma thrusters, like those deployed on larger-class satellites, do not work well. A more promising method of micropropulsion is electrospray.

Electrospray involves microscopic, hollow needles that use electricity to spray thin jets of fluid, pushing the spacecraft in the opposite direction. But the needles have drawbacks. They are intricate, expensive and easily destroyed.

To solve this problem, L. Brad King, Ron & Elaine Starr Professor in Space Systems at Michigan Tech, is creating a new kind of microthruster that assembles itself out of its own propellant when excited by a magnetic field. The tiny thruster requires no fragile needles and is essentially indestructible.

"We're working with a unique material called an ionic liquid ferrofluid," King says, explaining that it's both magnetic and ionic, a liquid salt. "When we put a magnet underneath a small pool of the ferrofluid, it turns into a beautiful hedgehog structure of aligned peaks. When we apply a strong electric field to that array of peaks, each one emits an individual micro-jet of ions."

The phenomenon is known as a Rosensweig instability. The peaks also heal themselves and re-grow if they are somehow damaged.

King came up with the idea of using ferrofluids for thrusters in 2012. He was trying to make an ionic liquid that behaved like a ferrofluid when he learned about a research team at the University of Sydney led by Brian Hawkett and Nirmesh Jain. They had developed a ferrofluid from magnetic nanoparticles made by the life sciences company Sirtex.

King's early work with the ferrofluid sample was pure trial and error; the results were good, but the physics were poorly understood. That's when the Air Force Office of Scientific Research (AFOSR) gave King a contract to research the fluid physics of ferrofluid.

Enter Jackson, whose doctoral work is advised by King.

"Typically among engineers, there are experimentalists who build and measure things, or there are modelers who simulate things," King says. "Brandon excels at both."

Working in King's Ion Space Propulsion Laboratory, Jackson conducted an experimental and computational study on the interfacial dynamics of the ferrofluid, and created a computational model of ionic liquid ferrofluid electrosprays.

"We wanted to learn what led up to emission instability in one single peak of the ferrofluid microthruster," Jackson says, who developed a model for a single peak and conducted rigorous testing to ensure the model was correct.

The team gained a much better understanding of the relationships between magnetic, electric and surface tension stresses. Some of the data gathered through the model surprised them.

"We learned that the magnetic field has a large effect in preconditioning the fluid electric stress," Jackson says, explaining this discovery might lead to a better understanding of the unique behaviors of ferrofluid electrosprays.

The AFOSR recently awarded King a second contract to continue researching the physics of ferrofluids, and he says, "Now we can take what we've learned, and instead of modeling a single peak, we'll scale it up and model multiple peaks."

Their next set of experiments will be more like a thruster, though a working thruster is still several years away. Although making 100 peaks or more, all thrusting identically, will be much more challenging.

"Often in the lab we'll have one peak working and 99 others loafing. Brandon's model will be a vital tool for the team going forward," King says. "If we are successful, our thruster will enable small inexpensive satellites with their own propulsion to be mass produced. That could improve remote sensing for better climate modeling, or provide better internet connectivity, which three billion people in the world still do not have."

The team has also begun collaborating with Juan Fernandez de la Mora, a professor of mechanical engineering and materials science at Yale University, one of the world's leading experts in electrospray.

In addition to spacecraft propulsion, ferrofluid electrospray technology could be useful in spectrometry, pharmaceutical production, and nanofabrication. Michigan Tech has a pending patent for the technology.

Media Contact

Allison Mills
awmills@mtu.edu
906-487-2343

 @michigantech

http://www.mtu.edu 

Allison Mills | EurekAlert!

More articles from Physics and Astronomy:

nachricht Computer model predicts how fracturing metallic glass releases energy at the atomic level
20.07.2018 | American Institute of Physics

nachricht What happens when we heat the atomic lattice of a magnet all of a sudden?
18.07.2018 | Forschungsverbund Berlin

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>