Supersonic laser-propelled rockets

October 29, 2014
The effectiveness of current laser-propulsion techniques is limited by the instability of supersonic gas flow, caused by shock waves that "choke" the inlet of the nozzle, reducing thrust. Those effects can be reduced with the help of laser ablation, redirecting the plasma plume so that it flows close to the interior walls of a supersonic nozzle and significantly improving the overall thrust. Credit: Y.Rezunkov/IOIE

Scientists and science fiction writers alike have dreamt of aircrafts that are propelled by beams of light rather than conventional fuels. Now, a new method for improving the thrust generated by such laser-propulsion systems may bring them one step closer to practical use.

The method, developed by physicists Yuri Rezunkov of the Institute of Optoelectronic Instrument Engineering, Russia and Alexander Schmidt of the Ioffe Physical Technical Institute in Saint Petersburg, Russia is described today in The Optical Society's (OSA) journal Applied Optics.

Currently, the maximum speed of a spacecraft is limited by the amount of solid or liquid fuel that it can carry. Achieving higher speeds means that more fuel must be burned—fuel that, inconveniently, has to be carried by the craft and hefted into space. These burdensome loads can be reduced, however, if a laser—one located at a remote location, and not actually on the spacecraft—were used to provide additional propulsive force.

A number of systems have been proposed that can produce such laser propulsion. One of the most promising involves a process called laser ablation, in which a pulsed laser beam strikes a surface, heats it up, and burns off material to create what is known as a plasma plume—a column of charged particles that flow off the surface. The outflowing of that plasma plume—essentially, exhaust—generates additional thrust to propel the craft.

In their Applied Optics paper, Rezunkov and Schmidt describe a new system that integrates a laser-ablation with the gas blasting nozzles of a spacecraft. Combining the two systems, the researchers found, can increase the speed of the gas flow out of the system to while reducing the amount of burned fuel.

The researchers show that the effectiveness of current laser-propulsion techniques is limited by factors including the instability of supersonic gases as they flow through the gas nozzle, as well as the production of shock waves that "choke" the inlet of the nozzle, reducing thrust. But those effects can be reduced with the help of a plasma plume that is redirected so that it will flow close to the interior walls of the nozzle. Coupling the ablation jet with supersonic gas flow through the nozzle, they find, significantly improves the overall thrust generated by the nozzle.

"Summarizing the data obtained, we can forecast the application of the supersonic laser propulsion techniques not only for launching small satellites to Earth orbits but also for additional acceleration of supersonic aircrafts to achieve Mach 10 and more," Rezunkov said.

Explore further: Ultrashort laser ablation enables novel metal films

More information: "Supersonic Laser Propulsion," Y. Rezunkov and A. Schmidt, Applied Optics, Vol. 53, Issue 31, pp. I55-I62 (2014). www.opticsinfobase.org/ao/abstract.cfm?URI=ao-53-31-I55&origin=search

Related Stories

Ultrashort laser ablation enables novel metal films

September 21, 2010

Laser ablation is well known in medical applications like dermatology and dentistry, and for more than a decade it has been used to vaporize materials that are difficult to evaporate for high-tech applications like deposition ...

Cool electron acceleration

June 4, 2013

Physicists from the Max-Planck-Institute of Quantum Optics produced electron pulses from a laser accelerator whose individual particles all have nearly the same, tuneable energy.

Experiment on Earth demonstrates effect observed in space

April 29, 2014

Streaming jets of high-speed matter produce some of the most stunning objects seen in space. Astronomers have seen them shooting out of young stars just being formed, X-ray binary stars and even the supermassive black holes ...

NASA team proposes to use laser to track orbital debris

October 28, 2014

(Phys.org) —As participation in space exploration grows worldwide, so does the impact of orbital debris—man-made "space junk" that poses significant hazards to live spacecraft and astronauts should they cross paths and ...

Recommended for you

Understanding nature's patterns with plasmas

August 23, 2016

Patterns abound in nature, from zebra stripes and leopard spots to honeycombs and bands of clouds. Somehow, these patterns form and organize all by themselves. To better understand how, researchers have now created a new ...

Light and matter merge in quantum coupling

August 22, 2016

Where light and matter intersect, the world illuminates. Where light and matter interact so strongly that they become one, they illuminate a world of new physics, according to Rice University scientists.

Measuring tiny forces with light

August 25, 2016

Photons are bizarre: They have no mass, but they do have momentum. And that allows researchers to do counterintuitive things with photons, such as using light to push matter around.

Stretchy supercapacitors power wearable electronics

August 23, 2016

A future of soft robots that wash your dishes or smart T-shirts that power your cell phone may depend on the development of stretchy power sources. But traditional batteries are thick and rigid—not ideal properties for ...

Spherical tokamak as model for next steps in fusion energy

August 24, 2016

Among the top puzzles in the development of fusion energy is the best shape for the magnetic facility—or "bottle"—that will provide the next steps in the development of fusion reactors. Leading candidates include spherical ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.