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LASER SYSTEM FOR

IGNITION

OF A CAR ENGINEOCTOBER 2014

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• Lean mixtures ignition;

• Short duration of combustion;

• Reduction of erosion effects;

• The ignition point position can be chosen;

• Ignition can be made in several points;

• Increase of the engine efficiency.

ADVANTAJES

• The laser dimension.

CHALLENGE

• Laser-induced ignition in internal combustion engines

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IMPORTANT PAPERS

• Laser Phys. Lett. 4(4), 322 (2007)H. Kofler, J. Tauer, G. Tartar, K. Iskra, J. Klausner, G. Herdin, and E. Wintner

Abstract: A compact high peak power, passively Q-switched, longitudinally diode-pumped laser was speciallyconstructed for laser ignition. Nd:YAG was chosen as laser active medium and Cr4+:YAG as thesaturable absorber medium. For pumping, a laser diode emitting at 808 nm with an output powerof up to 300 W and pulse duration of up to 500 µs was employed. Experimental studies were carried out to find the optimum laser design parameters. These are the output coupler reflectivity, initial transmission of the saturable absorber, doping concentration of the Nd:YAG, oscillator length and the pump light distribution within the Nd:YAG crystal. Single pulses at 1064 nm with energies of 6 mJ and durations under 1.5 ns were achieved in a TEM00 mode.

• Opt. Eng. 48(1), 014202 (2009)G. Kroupa, G. Frantz, and E. Winkelhofer

Abstract: A robust, miniaturized, diode-pumped high-energy neodymium doped yttrium aluminium garnet (Nd:YAG) laser with passive Q-switch generating 25 mJ at 3 ns has been demonstrated at repetition rates of up to 150 Hz. The device is designed for ignition of fuel air mixtures in internal combustion engines. The pump diodes and Peltier cooling are integrated in the laser head, giving a compact design with a small number of optical components for easy assembly. The laser was successfully operated as an optical spark plug on a test engine at high temperature and vibration levels.

• Laser Phys. 20(6), 1545 (2010)E. Schwarz, I. Muri, J. Tauer, H. Kofler, and E. Wintner

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JAPAN

• Opt. Express 16(24), 19891 (2008)H. Sakai, H. Kan, and T. Taira

• IEEE J. Quantum Electron. 46(2), 277 (2010)M. Tsunekane, T. Inohara, A. Ando, N. Kido, K. Kanehara, and T. TairaAbstract: The compact (electric spark plug size), diode-pumped, passively -switched Nd:YAG/Cr4+:YAG

microlaser was developed for ignition of engines. Output energy of 2.7 mJ per pulse and 11.7 mJ per four-pulse train with a pulse width of 600 ps and an M2 value of 1.2 were obtained at a pump duration of 500 ms. The optical-to-optical conversion efficiency was 19%. … The enhanced combustion by the microlaser ignition was successfully demonstrated in a constant-volume chamber at room temperature and atmospheric pressure. … Hundred percent ignition was successfully demonstrated in a lean mixture of A/F 17.2 by laser ignition, where electric spark plug ignition failed.

●

2008-2010

●

2010-2011

• CLEO 2011, Baltimore, Maryland, USA, 1-6 May 2011, presentation CMP1;N. Pavel, M. Tsunekane, K. Kanehara, and T. TairaAbstract: Compacts, few MW-level peak power, passively Q-switched Nd:YAG/Cr4+:YAG micro-lasers

with two-beam output were realized. The monolithic devices incorporate composite, all-polycrystalline ceramics components and can be used as multi-point igniters in internalcombustion engines.

●

2010-2011

• Opt. Express 19(10), 9378 (2011)N. Pavel, M. Tsunekane, and T. TairaAbstract: A passively Q-switched Nd:YAG/Cr:YAG4+ micro-laser with three-beam output was

realized. A single active laser source made of a composite, all-ceramicsNd:YAG/Cr4+:YAG monolithic cavity was pumped by three independent lines. At 5 Hz repetition rate, each line delivered laser pulses with ~2.4 mJ energy and 2.8-MW peak power. …. This kind of laser can be used for multi-point ignition of an automobile engine.

• The 1st Laser Ignition Conference (LIC ’13), 23-25 April 2013, Yokohama, Japan, presentation LIC3-1;T. Taira, S. Morishima, K. Kanehara, N. Taguchi, A. Sugiura, and M. Tsunekane

Abstract. The world first micro-laser ignited self-consisted gasoline engine vehiclehas been operated by “Giant Micro-Photonics”. Advantages of lean-mixture

combustion should also show benefits in realization of an efficient and clean electric power cogeneration system.

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GERMANY

• The 2nd Laser Ignition Conference (LIC ’14), 22-25 April 2014, Yokohama, Japan, presentation LIC3-2;

P. Wörner, Dr. H. Ridderbusch, J. Ostrinsky, and Dr. U. MeingastRobert Bosch GmbH, Robert Bosch Str. 2, 717701 Schwieberdingen, GERMANY

Abstract: Bosch can already look back on several years of research and predevelopment activities for alaser ignition system. We report a review of these activities and present some of their highlights.

Conclusion: Bosch has successfully developed the components of a laser ignition system and found technologicalsolutions to the many challenges: laser and optical design, engine behavior, integration in a compacthousing, window fouling and operating safety.Long-time engine tests in an early phase of the development process have proven the potential ofdurability and operational capability of the Bosch laser ignition system on stationary gas engines. Withits technology, Bosch is able to offer prototypes to engine manufacturers and is ready to start a seriesdevelopment as soon as the market needs this new technology.

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ROMANIA

• Laser Physics 19(11), 1-6 (2009)T. Dascalu and N. Pavel

• J. Opt. Electron. & Adv. Mat. 5(11), 1166 (2011)G. Salamu, O. Sandu, F. Voicu, M. Dejanu, D. Popa, S. Parlac, C. Ticos, N. Pavel, and T. Dascalu

• Laser Phys. Lett. 10(5), 055804 (2013)T. Dascalu, G. Salamu, O. Sandu, F. Voicu, and N. Pavel

National Institute for Laser, Plasma and Radiation Physics (INFLPR), Magurele, Bucharest R-077125, ROMANIA

FiberFiber--coupled diode endcoupled diode end--pumped Nd:YAG/Crpumped Nd:YAG/Cr4+4+:YAG lasers with one beam were realized (prototype level).:YAG lasers with one beam were realized (prototype level).

● 2011 ● 2013 ● 2014

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● 2013, November

INFLPR & Renault Technologie Roumanie (RTR), Bucharest, Romania

A Renault car engine was operated with one A Renault car engine was operated with one ‘‘laser sparklaser spark’’ and 3 conventional spark plugs.and 3 conventional spark plugs.

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●● 2014: A 4 A 4 ‘‘laser sparkslaser sparks’’ system was built at INFLPR.system was built at INFLPR.

It was operated in laboratoryIt was operated in laboratory..

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●May 2014; INFLPR & RTR

The 4 The 4 ‘‘laser sparklaser spark’’ system was controlled (at a RTR laboratory) by thesystem was controlled (at a RTR laboratory) by the

electronic control unit ECU of a Renault car engine.electronic control unit ECU of a Renault car engine.

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●May 2014; INFLPR & RTR:

A Renault car engine was operated only with the 4 A Renault car engine was operated only with the 4 ‘‘laser sparklaser spark’’ system!system!

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THANK YOU!

Acknowledgements: Romanian National Authority for Scientific Research, CNCS-UEFISCDI,

Project 58/2012 (PN-II-PT-PCCA-2011-3.2-1040)