Laser ignition

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Laser ignition is an alternative method for igniting mixtures of fuel and oxidiser. The phase of the mixture can be gaseous or liquid. The method is based on laser ignition devices that produce short but powerful flashes regardless of the pressure in the combustion chamber. Usually, high voltage spark plugs are good enough for automotive use, as the typical compression ratio of an Otto cycle internal combustion engine is around 10:1 and in some rare cases reach 14:1. However, fuels such as natural gas or methanol can withstand high compression without autoignition. This allows higher compression ratios, because it is economically reasonable, as the fuel efficiency of such engines is high. Using high compression ratio and high pressure requires special spark plugs that are expensive and their electrodes still wear out. Thus, even expensive laser ignition systems could be economical, because they would last longer. [1] [2] [3]

Contents

Further applications of laser ignition

Laser ignition is considered as a potential ignition system for non-hypergolic liquid rocket engines [4] [5] , reaction control systems [6] [7] [8] and firearms [9] which need an ignition system. Conventional ignition technologies like torch igniters are more complex in sequencing and need additional components like propellant feed lines and valves. [10] Therefore, they are heavy compared to a laser ignition system. Pyrotechnical devices allow only one ignition per unit and imply increased launch pad precautions as they are made of explosives.

See also

Related Research Articles

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<span class="mw-page-title-main">Rocketdyne J-2</span> Rocket engine

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<span class="mw-page-title-main">Rocket propellant</span> Chemical or mixture used as fuel for a rocket engine

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The TR-201 or TR201 is a hypergolic pressure-fed rocket engine used to propel the upper stage of the Delta rocket, referred to as Delta-P, from 1972 to 1988. The rocket engine uses Aerozine 50 as fuel, and N
2O
4 as oxidizer. It was developed in the early 1970s by TRW as a derivative of the lunar module descent engine (LMDE). This engine used a pintle injector first invented by Gerard W. Elverum Jr. and developed by TRW in the late 1950s and received US Patent in 1972. This injector technology and design is also used on SpaceX Merlin engines.

<span class="mw-page-title-main">Internal combustion engine</span> Engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber

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<span class="mw-page-title-main">Liquid apogee engine</span>

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References

  1. ↑ Marshall, Laura (September 2012). "Laser Car Ignition Dream Sparks Multiple Approaches". Photonics Spectra. Laurin Publishing. Retrieved 2014-04-07. "Laser plugs have no electrodes. Assuming replacement every 500 hours, this is $16,000 per year just in spark plug costs, compared to approximately $10,000 for the laser diode array. The usual advertised lifetime for laser diodes is over 10,000 hours, and, since the duty factor is 10 to 20 percent, they can potentially last for much longer."
  2. ↑ "New way to get that vital spark - University of Liverpool". Liv.ac.uk. 2008-10-31. Archived from the original on 2014-01-10. Retrieved 2014-02-01.
  3. ↑ Palmer, Jason (2011-04-24). "Lasers could replace spark plugs". BBC News.
  4. ↑ Thomas, Matthew E.; Bossard, John A.; Early, Jim; Trinh, Huu; Dennis, Jay; Turner, James (2001-12-05). Laser Ignition Technology for Bi-Propellant Rocket Engine Applications.
  5. ↑ Börner, Michael; Manfletti, Chiara; Oschwald, Michael (2015-07-01). "Laser Re-Ignition of a Cryogenic Multi-Injector Rocket Engine".{{cite journal}}: Cite journal requires |journal= (help)
  6. ↑ Hasegawa, Keichi; Kusaka, Kazuo; Kumakawa, Akinaga; Sato, Masahiro; Tadano, Makoto; Takahashi, Hideaki (2003). "Laser Ignition Characteristics of Gox/GH2 and Gox/GCH4 Propellants". 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit. American Institute of Aeronautics and Astronautics. doi:10.2514/6.2003-4906. ISBN   978-1-62410-098-7.
  7. ↑ Manfletti, Chiara (2014-01-01). "Laser Ignition of an Experimental Cryogenic Reaction and Control Thruster: Ignition Energies". Journal of Propulsion and Power. 30 (4): 952–961. doi:10.2514/1.B35115. ISSN   0748-4658.
  8. ↑ Börner, Michael; Manfletti, Chiara (2014-04-19). "Status and Perspectives of Laser Ignition of a Cryogenic Research RCS Thruster".{{cite journal}}: Cite journal requires |journal= (help)
  9. ↑ https://www.thefirearmblog.com/blog/2016/12/08/laser-ignition-system-voere-x3-rifle/
  10. ↑ Huzel, Dieter K. (1992-01-01). Modern Engineering for Design of Liquid-Propellant Rocket Engines. AIAA. ISBN   9781600864001.
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