Menu
About Science
Study reveals why the leopard got its spots
Allergy risk linked to time of first trimester
Hubble reveals furthest galaxy yet
Scientists confirm water from lunar probe
Researchers power up tiny batteries
Plants clean air better than expected
Haiti fault capable of another big quake
Japanese man joins growing genome ranks
NASA releases report into balloon crash
Tree's ability to soak up CO2 has limits
Ground coffee helps robot get a grip
Assassin bugs lure arachnid snack
Research reveals spring in ostrich's step
Lizard gender bends at altitude
Study suggests early primates out of Asia
Flamingos boost their colour to find a mate
Globular clusters more than one-off event
Ancient Africans first to use sharp tools
Grass could turn toxic waste into energy
Earth-like planets may be common
Natural born cell killers
Fingers spot typo ahead of the brain
Ecofriendly styrofoam from milk and clay
Study proves exercise boosts immune system

Researchers put spark into scramjets
It may not help start a troublesome lawnmower, but Australian researchers have developed a 'spark plug' that will work in a jet travelling at 10,000 kilometres an hour.

Researchers at the University of New South Wales at the Australian Defence Force Academy (UNSW@ADFA), have shown powerful lasers can be used to ignite the supersonic airflows that help power so-called scramjet engines.

Scramjets are air-breathing engines capable of travelling between five and 12 times the speed of sound. Although scramjet technology has been known to work since the 1950s, it has proven difficult to achieve in practice.

Dr Sean O'Byrne, lead researcher in the UNSW@ADFA laser diagnostics group, says one of the problems is how to maintain combustion in the supersonic air flow because the fuel must be injected, mixed, ignited, and burned within a few thousandths of a second.

He says their laser technology may be a solution and is due to present the unpublished work at the American Institute of Aeronautics and Astronautics Aerospace Sciences Conference in Florida in January.

"[Aeronautical engineers are] just at the point where they've proved scramjets work, now there is a lot of engineering to be done," he says.
Providing a kick start

Because the scramjet requires extremely high speeds of air to flow through the engine to work, it requires another form of engine to first get it to that velocity.

The problem then is how to create a 'spark plug' that will keep working at such high speeds.

O'Byrne says previous approaches have effectively used a giant arc like the one in an arc welder that uses a whole lot of energy to ensure the flame would not go out.

"But you may use as much power to produce the spark as you generate for thrust, so it is not really efficient," says O'Byrne.

Instead O'Byrne and PhD student Stefan Brieschenk, have focused a high-powered laser on the fuel jet, which creates a precise spark in the hydrogen fuel.

It does this through a phenomenon known as cascade ionisation, which occurs when the high-intensity beam literally "rips electrons off" the hydrogen molecule, creating a plasma that is the "spark".

The spark has peak temperatures approaching 100,000C, compared with a conventional electrical spark of a few thousand degrees Celsius. At this temperature the hydrogen molecules are torn apart and they become highly reactive and accelerate the reaction between the fuel and air.

The researchers proved the concept in a hypersonic wind tunnel by creating conditions where hydrogen would not burn, and then using this approach to ignite it.

Importantly, says O'Byrne, because each laser pulse lasts for a few nanoseconds it requires less energy than a continuous electrical spark.

He says the laser-ignition may also have applications in generating greener energy through improved ignition of gas-fired engines for power generation.

Print
Researchers put spark into scramjets
Fish found making their own 'mozzie' nets
Japan confirms asteroid dust on outback probe
Genetech pioneer awarded science prize
Scientists capture anti-matter atoms
Study reveals Icelandic eruption build-up
Astronomers spot galactic intruder
Open-mouthed laughter appreciated most
Financial crisis causes dip in CO2 levels
Puberty genes linked to body fat
Face shields needed for combat: study
Organically-grown vegies not more nutritious
Bloodstains could give age away
Models show pterosaurs flew long, slow
Marsupial carnivores were underestimated
Massive black hole collision revealed
Jet-lag causes long term memory loss
Sunken tanks could detect secret nukes
Dino demise supersized the mammals
Binge drinking linked to heart disease
Cassini sniffs oxygen on Saturnian moon
Image shows echoes from before big bang
Research uncovers diamond's soft side
World warmer, but trends at odds: report
Humans caused megafauna demise: expert
The world: Four degrees warmer
Blood vessels show pollution, heart disease link
Young great whites don't have the bite
Menu
Dolphin social network good for calves
Is fish-oil Alzheimer snake-oil?
Cosmic rays trace Sun's journey through space
Marsupial mole mystery solved
Scientists warn of new polio virus strain
Oldest known stone axe found in Arnhem Land
Fly-by captures first comet photos
Dead quasar's ghostly glow reignites debate
Mum and Dad tell us how to wear our genes
New images expand solar flare knowledge
Experts urge caution on Snowy cloud seeding
First little Big Bangs created at CERN
Tarantulas help map the fear factor
Neanderthal brains developed differently
Whales showing more sun damage
Bush cricket has the biggest balls of all
Giant gamma bubbles found in Milky Way
Complex life possible earlier than first thought
Happiness evades wandering minds?
Cat lapping defies gravity
Physics unravels wet dog shake
Hubble captures rare galactic view
Early wrinkles no sign of an early grave
World's forests suffer from 'leakage'
Visit Statistics
http://google.com/

http://bing.com/

https://gepatit-info.top/

https://serdechnic.com/

https://buy-meds24.com/

https://dverirespekt.ru/

https://www.sribno.net/

https://undergroundcityphoto.com/

https://detskiezabolevaniya.com/

http://grafaman.ru/

http://innoslicon.com/html/product/index.htm

https://yginekologa.com/

https://yes-com.com/

https://www.baikaleminer.com/

https://bitmaein.com/shop

https://www.artdeko.info/

https://aerodizain.com/

http://xn--d1abj0abs9d.in.ua/

http://lider82.ru/

http://sta-grand.ru/

http://snabs.kz/

https://sky-mine.ru/

https://rybalka-opt.ru/

http://snegozaderzhatel.ru/

https://xn--e1aaajzchnkg.ru.com/

http://hit-kino.ru/

http://www.regionshop.biz/

https://xn--80aaafbn2bc2ahdfrfkln6l.xn--p1ai/

https://pp-budpostach.com.ua/

https://vykup-avto-krasnodar.ru/

https://gcup.ru/

https://mega-polis.biz.ua/

http://vanrise.com.ua/

http://infra-e.ru/

https://veterinariya.com/

https://ponosanet.com/

https://cariestop.com/

https://proartrit.com/

https://elonm.ru/

https://nakozhe.com/

https://spinanebolit.com/

http://zameskino.ru/

http://kinoprinc.ru/

http://pospektr.ru/

http://buypillsonline24h.com/

http://komputers-best.ru/

https://komp-pomosch.ru/