OSA's Digital Library

Energy Express

Energy Express

  • Editor: Christian Seassal
  • Vol. 21, Iss. S6 — Nov. 4, 2013
  • pp: A1102–A1112
« Show journal navigation

High power fiber delivery for laser ignition applications

Azer P. Yalin  »View Author Affiliations


Optics Express, Vol. 21, Issue S6, pp. A1102-A1112 (2013)
http://dx.doi.org/10.1364/OE.21.0A1102


View Full Text Article

Acrobat PDF (3467 KB)





Browse Journals / Lookup Meetings

Browse by Journal and Year


   


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools

Share
Citations

Abstract

The present contribution provides a concise review of high power fiber delivery research for laser ignition applications. The fiber delivery requirements are discussed in terms of exit energy, intensity, and beam quality. Past research using hollow core fibers, solid step-index fibers, and photonic crystal and bandgap fibers is summarized. Recent demonstrations of spark delivery using large clad step-index fibers and Kagome photonic bandgap fibers are highlighted.

© 2013 OSA

1. Introduction

Despite its potential advantages, laser ignition is not currently used in commercial or industrial combustion systems. In some application areas, for example automotive, cost is a key factor. However, in applications such as large industrial engines and turbines for power-generation or aircraft, the cost of solid state pulsed lasers can be viable. In all practical applications, the overall system must meet requirements of performance, reliability, durability, safety, and cost. The majority of laboratory research has employed open-path beam delivery using mirrors to transmit the laser pulse to the combustion volume. Over short distances such configurations may be feasible but in many cases this type of beam delivery is impractical, for example for use on large industrial engines where there are many ignition locations, or in any application where the laser must be remotely located and transmitted over a relatively long path length or one where there is significant vibration or thermal drift of hardware. For such cases, three general system architectures are being considered. The first approach is based on reliable and compact laser systems that can be mounted in close proximity to the ignition location. Several diode pumped solid-state lasers (using both side- and end-pumping) with passive Q-switches have been developed for this purpose (e.g [14

14. H. Kofler, J. Tauer, G. Tartar, K. Iskra, J. Klausner, G. Herdin, and E. Wintner, “An innovative solid-state laser for engine ignition,” Laser Phys. Lett. 4(4), 322–327 (2007). [CrossRef]

, 15

15. G. Kroupa, G. Franz, and E. Winkelhofer, “Novel miniaturized high-energy Nd-YAG laser for spark ignition in internal combustion engines,” Opt. Eng. 48(1), 014202 (2009). [CrossRef]

].) including ceramic gain materials [16

16. N. Pavel, M. Tsunekane, K. Kanehara, and T. Taira, “Composite all-ceramics, passively Q-switched Nd:YAG/Cr4+:YAG monolithic micro-laser with two-beam output for multi-pointiIgnition,” in Conference on Lasers and Electro Optics, Baltimore, MD (2011).

, 17

17. M. Tsunekane, T. Inohara, K. Kanehara, and T. Taira, “Micro-solid-state laser for ignition of automobile engines,” in Advances in Solid State Lasers Development and Applications, M. Grishin, ed. (InTech, 2010).

]. The second approach is to use a single remotely located pump source (power ~300-600 W) that is transmitted through optical fiber to gain element(s) located at the ignition site(s) [7

7. G. Herdin, “GE Jenbacher`s update on laser ignited engines,” ICEF2006–1547, ASME ICE Fall Technical Conference, Sacramento, CA, 2006. [CrossRef]

, 18

18. D. L. McIntyre, S. D. Woodruff, and J. S. Ontko, “Lean-burn stationary natural gas reciprocating engine operation with a prototype fiber coupled diode end pumped passively q-switched laser spark plug” ICES2009–76013, ASME ICE Spring Technical Conference, Milwaukee, WI, (2009). [CrossRef]

, 19

19. J. Tauer, H. Kofler, and E. Winter, “Laser-initiated ignition,” Laser & Photonics Reviews 4(1), 99–122 (2010). [CrossRef]

]. The third method, which is the focus of this contribution, is to have a single remotely located laser source and to deliver the high peak-power (~MW) pulses to the individual ignition location(s) via fiber optics. The approach is immediately attractive owing to its potential simplicity (low-cost) but the needed fiber delivery is technically challenging.

In applications where there are multiple ignition sites (e.g., 4-20 engine cylinders), a distributed approach as schematically shown in Fig. 2 with a single laser and fiber optic delivery may be preferred [4

4. S. Joshi, A. P. Yalin, and A. Galvanauskas, “Use of hollow core fibers, fiber lasers, and photonic crystal fibers for spark delivery and laser ignition in gases,” Appl. Opt. 46(19), 4057–4064 (2007). [CrossRef] [PubMed]

, 8

8. H. El-Rabii and G. Gaborel, “Laser ignition of flammable mixtures via a solid core optical fiber,” App. Phys. B-Lasers and Optics 87(1), 139–144 (2007). [CrossRef]

, 20

20. D. Graham-Rowe and R. Won, “Lasers for engine ignition,” Nat. Photonics 2(9), 515–517 (2008). [CrossRef]

22

22. E. Schwarz, I. Muri, J. Tauer, H. Kofler, and E. Wintner, “Laser-induced ignition by optical breakdown,” Laser Phys. 20(6), 1545–1553 (2010). [CrossRef]

]. Such an approach could be advantageous because only a single laser source is needed and it could be positioned away from the increased temperature and vibration of the combustion location; however, fiber delivery has been challenging. Typical ignition laser sources have peak power of ~1-10 MW which is much higher than is typically used for fiber delivery and spark formation imposes the additional requirement of high beam quality (spatial-quality) at the fiber exit so that the light can be refocused to form a spark. Several researchers have concluded that fiber delivery is intractable or very challenging [19

19. J. Tauer, H. Kofler, and E. Winter, “Laser-initiated ignition,” Laser & Photonics Reviews 4(1), 99–122 (2010). [CrossRef]

, 20

20. D. Graham-Rowe and R. Won, “Lasers for engine ignition,” Nat. Photonics 2(9), 515–517 (2008). [CrossRef]

, 23

23. A. Stakhiv, R. Gilber, H. Kopecek, A. M. Zheltikov, and E. Wintner, “Laser ignition of engines via optical fibers?” Laser Phys. 14, 738–747 (2004).

, 24

24. J. Tauer, H. Kofler, E. Schwarz, and E. Wintner, “Transportation of megawatt millijoule laser pulses via optical fibers?” Central European Journal of Physics 8(2), 242–248 (2010). [CrossRef]

] and indeed success with conventional step-index fibers has been limited.
Fig. 2 Schematic diagram of fiber delivered laser ignition from a single laser to multiple engine cylinders. The laser comprises a pump source and oscillator while a multiplexer is used to route the beam to different fiber channels (from [19]).

The present contribution addresses the technical requirements and challenges of fiber delivery, summarizes past research, and highlights recent findings showing spark delivery and ignition that have occurred since publication of past reviews [19

19. J. Tauer, H. Kofler, and E. Winter, “Laser-initiated ignition,” Laser & Photonics Reviews 4(1), 99–122 (2010). [CrossRef]

, 23

23. A. Stakhiv, R. Gilber, H. Kopecek, A. M. Zheltikov, and E. Wintner, “Laser ignition of engines via optical fibers?” Laser Phys. 14, 738–747 (2004).

, 24

24. J. Tauer, H. Kofler, E. Schwarz, and E. Wintner, “Transportation of megawatt millijoule laser pulses via optical fibers?” Central European Journal of Physics 8(2), 242–248 (2010). [CrossRef]

]. For multi-cylinder engines the fiber delivery should be combined with a multiplexer to distribute the individual source to multiple fibers. The multiplexing may be based on galvanometers [25

25. A. P. Yalin, A. R. Reynolds, S. Joshi, M. W. Defoort, B. Willson, Y. Matsuura, and M. Miyagi, “Development of a fiber delivered laser ignition system for natural gas engines” (2006). ICEF2006–1574, ASME ICE Fall Technical Conference, Sacramento, CA, 2006. [CrossRef]

], mechanically rotating optics [18

18. D. L. McIntyre, S. D. Woodruff, and J. S. Ontko, “Lean-burn stationary natural gas reciprocating engine operation with a prototype fiber coupled diode end pumped passively q-switched laser spark plug” ICES2009–76013, ASME ICE Spring Technical Conference, Milwaukee, WI, (2009). [CrossRef]

], modulators [26

26. B. Bihari, S. B. Gupta, R. R. Sekar, J. Gingrich, and J. Smith, “Development of advanced laser ignition system for stationary natural gas reciprocating engines,” ICEF2005–1325, ASME ICE Fall Technical Conference, Ottawa, Canada, (2005). [CrossRef]

], or compact scanners as are used for laser displays, but this aspect is beyond the scope of the current contribution. The layout of the remainder of the paper is as follows. The basic requirements for fiber output parameters are discussed in Section 2. Research efforts using hollow core fibers, step-index fibers, photonic crystal and bandgap fibers, and fiber lasers are presented in Sections 3-6 respectively. Finally, short conclusions and outlook to future work is presented in Section 7.

2. Fiber output parameters and basic considerations

To enable ignition, the fiber output must allow formation of a laser induced plasma with sufficient energy. While resonant schemes and thermal ignition are of long term interest, we fix the discussion by considering widely used non-resonant breakdown with nanosecond duration Nd:YAG lasers (1064 nm). The fiber must be able to reliably transmit high peak-power (megawatt) pulses with sufficient beam quality (low M2) to allow refocusing of the output beam to an intensity exceeding the breakdown threshold of the gas, i.e., IBD,Air≅100-300 GW/cm2 for 10 ns, 1064 nm pulses at atmospheric pressure, and scales with pressure as ~p-0.5 [27

27. A. Sircar, R. K. Dwivedi, and R. K. Thareja, “Laser induced breakdown of Ar, N-2 and O-2 gases using 1.064, 0.532, 0.355 and 0.266 μm m radiation,” App. Phys. B-Lasers and Optics 63, 623–627 (1996).

, 28

28. T. X. Phuoc, “Laser spark ignition: experimental determination of laser-induced breakdown thresholds of combustion gases,” Opt. Commun. 175(4-6), 419–423 (2000). [CrossRef]

]. For reciprocating engines, the motored pressure at time of ignition may be of order 10 bar with mixtures generally have relatively high air volume fractions, for example in the range of >~90% for lean burn natural gas engines. On the other hand, for aero-turbines the pressures can be in the vicinity of 0.2 bar so that higher focused intensities are needed. The aero-turbines also typically employ two-phase mixtures with breakdown intensities for the liquid droplets being only ~1 GW/cm2 [29

29. W. F. Hsieh, J. H. Eickmans, and R. K. Chang, “Internal and external laser-induced avalanche breakdown of single droplets in an argon atmosphere,” JOSA B-Optical Physics 4(11), 1816–1820 (1987). [CrossRef]

, 30

30. R. G. Pinnick, P. Chylek, M. Jarzembski, E. Creegan, V. Srivastava, G. Fernandez, J. D. Pendleton, and A. Biswas, “Aerosol-induced laser breakdown thresholds - wavelength dependence,” Appl. Opt. 27(5), 987–996 (1988). [CrossRef] [PubMed]

]; however, typical droplet volume fractions are low enough that the focused beam generally does not overlap a droplet.

In addition to allowing spark formation, ignition requires that the plasma energy (absorbed from the laser) exceed the minimum ignition energy (MIE). MIE varies with applications but we generally consider the case of lean natural gas engines for which one has MIE of ~10-20 mJ [19

19. J. Tauer, H. Kofler, and E. Winter, “Laser-initiated ignition,” Laser & Photonics Reviews 4(1), 99–122 (2010). [CrossRef]

, 23

23. A. Stakhiv, R. Gilber, H. Kopecek, A. M. Zheltikov, and E. Wintner, “Laser ignition of engines via optical fibers?” Laser Phys. 14, 738–747 (2004).

, 35

35. H. Kopecek, H. Maier, G. Reider, F. Winter, and E. Wintner, “Laser ignition of methane-air mixtures at high pressures,” Exp. Therm. Fluid Sci. 27(4), 499–503 (2003). [CrossRef]

]. Energy requirements for aero-turbines tend to be higher, for example some basic studies show required energies of ~30-60 mJ for reliable ignition [36

36. H. El-Rabii, G. Gaborel, J. P. Lapios, D. Thévenin, J. C. Rolon, and J. P. Martin, “Laser spark ignition of two-phase monodisperse mixtures,” Opt. Commun. 256(4-6), 495–506 (2005). [CrossRef]

], while other experiments in more realistic rigs use in excess of 100-200 mJ [11

11. R. Oldenborg, J. Early, and C. Lester, “Advanced ignition and propulsion technology program,” (Los Alamos National Laboratory, 1998).

, 37

37. G. C. Gebel, T. Mosbach, W. Meier, and M. Aigner, “Laser-induced ignition of kerosene in a model combustor,” in Proceedings of the European Combustion Meeting0612011.

39

39. G. C. Gebel, T. Mosbach, W. Meier, and M. Aigner, “An experimental investigation of kerosene droplet breakup by laser-induced blast waves,” in Proceedings of ASME Turbo Expo 2012021505 (Coopenhagen, Denmark, 2012). [CrossRef]

]. In implementations that use a window to access (seal) the combustion volume, an additional constraint on the focusing configuration is the need to have an optical fluence that is sufficiently high to maintain window cleanliness (through laser self-cleaning) but sufficiently low to not damage the combustion window, which corresponds to a fluence in the range of ~0.5 – 10 J/cm2 [40

40. T. X. Phuoc, “A comparative study of the photon pressure force, the photophoretic force, and the adhesion van der Waals force,” Opt. Commun. 245(1-6), 27–35 (2005). [CrossRef]

].

3. Hollow core fibers

Coated hollow core fibers have been demonstrated for spark delivery and laser ignition of a gas engine. As shown in Fig. 3, the fibers used in these experiments were cyclic olefin polymer-coated silver hollow fibers developed and manufactured at Tohoku University (Japan) [41

41. Y. Matsuura, A. Tsuchiuchi, H. Noguchi, and M. Miyagi, “Hollow fiber optics with improved durability for high-peak-power pulses of Q-switched Nd:YAG lasers,” Appl. Opt. 46(8), 1279–1282 (2007). [CrossRef] [PubMed]

, 42

42. Y. Matsuura, G. Takada, T. Yamamoto, Y. W. Shi, and M. Miyagi, “Hollow fibers for delivery of harmonic pulses of Q-switched Nd:YAG lasers,” Appl. Opt. 41(3), 442–445 (2002). [CrossRef] [PubMed]

]. The hollow fibers were originally developed for delivery of mid-infrared lasers such as CO2 (λ = 10.6 μm) and Er:YAG (λ = 2.94 μm), which cannot be delivered by silica glass fibers because of absorption loss. The coated fibers are flexible and have typical inner (hollow) diameters of 500-1000 μm and lengths of several meters. The maximum temperature the fibers can withstand is ~500 K which is reasonable for most targeted environments, though lifetime and reliability needs to be more fully considered [43

43. J. P. Parry, T. J. Stephens, J. D. Shephard, J. D. C. Jones, and D. P. Hand, “Analysis of optical damage mechanisms in hollow-core waveguides delivering nanosecond pulses from a Q-switched Nd:YAG laser,” Appl. Opt. 45(36), 9160–9167 (2006). [CrossRef] [PubMed]

]. Note that uncoated hollow fibers (capillaries) can also be used for light delivery, but they tend to have low transmission and to be extremely susceptible to bending loss [23

23. A. Stakhiv, R. Gilber, H. Kopecek, A. M. Zheltikov, and E. Wintner, “Laser ignition of engines via optical fibers?” Laser Phys. 14, 738–747 (2004).

].
Fig. 3 Left: Schematic diagram of coated hollow fiber (from [21]). Right: Photograph of spark formation at output of coated hollow fiber (from [21]).

Spark formation in air at the output of coated hollow fibers has been demonstrated [4

4. S. Joshi, A. P. Yalin, and A. Galvanauskas, “Use of hollow core fibers, fiber lasers, and photonic crystal fibers for spark delivery and laser ignition in gases,” Appl. Opt. 46(19), 4057–4064 (2007). [CrossRef] [PubMed]

, 21

21. A. P. Yalin, M. DeFoort, B. Willson, Y. Matsuura, and M. Miyagi, “Use of hollow-core fibers to deliver nanosecond Nd:YAG laser pulses to form sparks in gases,” Opt. Lett. 30(16), 2083–2085 (2005). [CrossRef] [PubMed]

, 44

44. A. P. Yalin, M. W. Defoort, S. Joshi, D. Olsen, B. Willson, Y. Matsuura, and M. Miyagi, “Laser ignition of natural gas engines using fiber delivery,” ICEF2005–1336, ASME ICE Fall Technical Conference, Ottawa, Canada, (2005). [CrossRef]

]. A single lens was used to launch laser light from a Q-switched Nd:YAG (1064 nm) into the fiber while a lens pair was used to focus light exiting the fiber into a small spot where a spark may form. Fibers of 0.7 and 1 mm diameter have been used with lengths of 1 and 2 meters. For some launch conditions sparks can (inadvertently) form at the fiber input, though this can be largely avoided by flowing helium gas at the input or by pulling vacuum. For 2 m length straight fibers of diameter 1 mm, the energy transmission was in the range of 80 to 90% [4

4. S. Joshi, A. P. Yalin, and A. Galvanauskas, “Use of hollow core fibers, fiber lasers, and photonic crystal fibers for spark delivery and laser ignition in gases,” Appl. Opt. 46(19), 4057–4064 (2007). [CrossRef] [PubMed]

]. Low launch angles (~0.02) were used to excite a minimum number of modes [45

45. R. K. Nubling and J. A. Harrington, “Launch conditions and mode coupling in hollow-glass waveguides,” Opt. Eng. 37(9), 2454–2458 (1998). [CrossRef]

] allowing low angular divergence of light exiting the fiber and optimum exit beam quality of M2~15. With pulse energy of ~35 mJ the achievable focal intensity was ~470 GW/cm2 well above the break down threshold intensity. Sparking at atmospheric pressure was achieved for 98% of laser shots, with the occasional misfires attributed to the varying multimode spatial profile (hot spots) in the exit beam. For straight configurations, the damage threshold of ~1 GHz/cm2 is comparable to that for solid core fiber, and the main advantage of hollow core fibers lies in their improved output beam quality (smaller output angle) for a given core diameter. Bending loss studies showed that increased fiber bending reduced the energy transmission and reduced the beam quality at the fiber exit. For example, for 2-m length fibers with the first 1-m of straight, bending of radius of curvature (ROC) = 1.5 m yielded similar performance to the straight fiber, but with bending of ROC = 1 m sparking was no longer achievable at atmospheric pressure. Sparking at elevated pressure conditions is easier, for example at pressure of 14 bars, sparking was achieved with a 2-m fiber with ROC of 50 cm and bent fiber length of 1 m. Damage of the coated hollow fibers is generally due to optical damage of the reflective coating [43

43. J. P. Parry, T. J. Stephens, J. D. Shephard, J. D. C. Jones, and D. P. Hand, “Analysis of optical damage mechanisms in hollow-core waveguides delivering nanosecond pulses from a Q-switched Nd:YAG laser,” Appl. Opt. 45(36), 9160–9167 (2006). [CrossRef] [PubMed]

]. Varying the thickness and smoothness of the reflective coating can influence the damage threshold but there is a tradeoff with transmission efficiency and bend loss.

Despite the bending loss limitations, the coated hollow fibers (in relatively straight configurations) have been used for ignition of a single-cylinder of an inline 6-cylinder Waukesha VGF turbocharged natural-gas engine [44

44. A. P. Yalin, M. W. Defoort, S. Joshi, D. Olsen, B. Willson, Y. Matsuura, and M. Miyagi, “Laser ignition of natural gas engines using fiber delivery,” ICEF2005–1336, ASME ICE Fall Technical Conference, Ottawa, Canada, (2005). [CrossRef]

]. The engine has a nominal rating of 400 bhp at 1800 rpm with engine displacement of 18 liters. The focusing optics were integrated into an optical sparkplug which threaded into the sparkplug port of the engine cylinder and provided optical access to the cylinder through a sapphire window. The tests demonstrated 100% reliable ignition of the laser cylinder (with the remaining cylinders running on conventional spark ignition). The timing of the non-laser cylinders was kept at the original setting, nominally 14° before-top-dead-center (BTDC). The timing of the laser ignited cylinder was controlled independently, and retarded to 8° BTDC. Even with this delay, the peak pressure of the laser cylinder was reached before all other cylinders indicating an increased rate of heat release. Bihari and colleagues have also examined the use of coated hollow fibers for ignition using 532 nm radiation [46

46. B. Bihari, S. B. Gupta, R. R. Sekar, J. Gingrich, and J. Smith, “Development of advanced laser ignition system for stationary natural gas reciprocating engines,” ICEF2005–1325, ASME ICE Fall Technical Conference, Ottawa, Canada,(2005). [CrossRef]

]. They were able to achieve spark formation at the fiber output using fibers of diameter 0.5, 0.7, and 1 mm. Using the hollow core fibers, the team also operated a Bombardier BSCRE-04 engine with the coupling set-up mounted such that it makes an angle of 15° with respect to the spark plug in the engine head.

4. Step-index silica fibers

The large clad fibers were used for a single-cylinder engine demonstration on a Waukesha Co-operative Fuel Research (CFR) engine converted to run on bottled methane [51

51. N. Wilvert, S. Joshi, and A. Yalin, “On comparative engine performance testing with fiber delivered laser ignition and electrical ignition,” ICEF2012–92007, ASME ICE Fall Technical Conference, Vancouver, Canada, (2012). [CrossRef]

]. These tests, schematically shown in Fig. 5 , used a large clad fiber with length of 2.85 m, core diameter of 400 µm, and clad diameter of 720 µm through which 11 mJ pulses of 25 ns duration (M2 = 5.1 and energy of 7 mJ at fiber exit). The final optical spark plug which focused the fiber output housed a diverging lens followed by a collimating lens and then a 10 mm focal length focusing lens (GradiumTM). (The role of the diverging lens was to shorten the length of the overall plug by more strongly expanding the beam exiting the fiber). A 3 mm thick sapphire window with copper gaskets sealed the optical spark plug from high pressure combustion gases in the engine cylinder. The ignition timing was optimized for the electrical ignition system and the laser firing time was set to match that of the electric spark plug. The final output beam from the optical plug could form sparks in pressures as low as 3.5 bar which guaranteed sparking at higher pressures and allowed engine startup without changing the ignition timing. The fiber delivered laser ignition system allowed reliable spark formation and acquisition of combustion data [51

51. N. Wilvert, S. Joshi, and A. Yalin, “On comparative engine performance testing with fiber delivered laser ignition and electrical ignition,” ICEF2012–92007, ASME ICE Fall Technical Conference, Vancouver, Canada, (2012). [CrossRef]

]. A practical concern, which can limit spark formation, is the sensitivity of the fiber output beam quality to stresses from fiber positioning and mounting (owing to micro-bending beam quality degradation). More research is needed in this area as it was necessary to use low-stress mounting and adjust the fiber position to optimize the output.
Fig. 5 Experimental Setup for fiber delivered laser ignition (from [49]). (a) optic setup, (b) fiber configuration and path. 1) Laser, 2) Mirror, 3) Half Waveplate, 4) Polarizer, 5) Focusing Lens, 6) Fiber Holder, 7) Fiber, 8) Optical Spark Plug, and 9) Single Cylinder Engine.

5. Photonic crystal and photonic bandgap fibers

In this section we summarize research on photonic crystal fibers (PCFs) and photonic bandgap fibers (PBGs) which employ periodic hole structures within the (silica) fiber material to modify the refractive index in such a way that one has efficient light guiding including single mode operation [57

57. A. Bjarklev, J. Broeng, and A.-S. Bjarklev, Photonic Crystal Fibers (Springer, 2003).

]. A PBG fiber with a 19 cell defect in the center was used to transmit ~0.5 mJ Nd:YAG pulses of duration 65 ns through a 2-m length fiber [58

58. J. D. Shephard, F. Couny, P. S. J. Russell, J. D. C. Jones, J. C. Knight, and D. P. Hand, “Improved hollow-core photonic crystal fiber design for delivery of nanosecond pulses in laser micromachining applications,” Appl. Opt. 44(21), 4582–4588 (2005). [CrossRef] [PubMed]

]. The authors believe higher pulse energies may be possible with improved mode matching. Tauer et al. have delivered pulses with energy of ~0.8 mJ and duration ~10 ns through a PBG fiber with 15 μm core-size and transmission of 82% [59

59. J. Tauer, F. Orban, H. Kofler, A. B. Fedotov, I. V. Fedotov, V. P. Mitrokhin, A. M. Zheltikov, and E. Wintner, “High-throughput of single high-power laser pulses by hollow photonic band gap fibers,” Laser Phys. Lett. 4(6), 444–448 (2007). [CrossRef]

]. Another researcher group transmitted picosecond pulse trains of 1064 nm light from an Nd:YAG laser through PBGs with inner core diameter of 13 microns. The maximum total energy that could be transmitted was approximately 1 mJ from a pulse train consisting of ~40 pulses each of 40 ps duration (25 μJ per pulse) [23

23. A. Stakhiv, R. Gilber, H. Kopecek, A. M. Zheltikov, and E. Wintner, “Laser ignition of engines via optical fibers?” Laser Phys. 14, 738–747 (2004).

, 60

60. S. O. Konorov, A. B. Fedotov, O. A. Kolevatova, V. I. Beloglazov, N. B. Skibina, A. V. Shcherbakov, E. Wintner, and A. M. Zheltikov, “Laser breakdown with millijoule trains of picosecond pulses transmitted through a hollow-core photonic-crystal fibre,” J. Phys. D Appl. Phys. 36(12), 1375–1381 (2003). [CrossRef]

]. It was speculated that higher (total) pulse energies of ~100 mJ may be possible with a similar approach. Michaille et al. performed a study of high power transmission through both PBG and PCF fibers with comparison against a theoretical model [61

61. D. M. T. L. Michaille, C. R. Bennett, T. J. Shephard, C. Jacobsen, and T. P. Hansen, “Damage threshold and bending properties of photonic crystal and photonic bandgap optical fibers,” presented at the Proc. SPIE 5618 (2004). [CrossRef]

]. The lower than expected damage threshold for the PBG fibers was attributed to laser-induced heating causing strain in the silica lattice. Ignition of rich methane-air mixtures at high pressures has been shown with 0.15 mJ transmitted through a hollow core PBG fiber [62

62. A. H. Al-Janabi, “Transportation of nanosecond laser pulses by hollow core photonic crystal fiber for laser ignition,” Laser Phys. Lett. 2(11), 529–531 (2005). [CrossRef]

], though conditions were favorable for ignition with low energy. The above results, while promising, generally have employed pulse energies less than is needed for practical applications. Owing to the inherent coupling between the single-mode output and the fiber dimension and geometry, increasing the transmitted pulse energies in PBGs and PCFs is challenging. Larger core (“rod-like”) PCFs may allow transmission of higher energies but if the fibers cannot be bent then they are not suitable for practical delivery [63

63. C. D. Brooks and F. Di Teodoro, “Multimegawatt peak-power, single-transverse-mode operation of a 100 μm core diameter, Yb-doped rodlike photonic crystal fiber amplifier ,” App. Phys. Lett . 89111119 (2006).

]. Use of longer pulse durations may be of interest but damage and non-linear effects must be considered. Polymer fiber PBGs with one-dimensional Bragg gratings have also recently shown high optical output powers [64

64. Z. Ruff, D. Shemuly, X. A. Peng, O. Shapira, Z. Wang, and Y. Fink, “Polymer-composite fibers for transmitting high peak power pulses at 1.55 microns,” Opt. Express 18(15), 15697–15703 (2010). [CrossRef] [PubMed]

]

6. Fiber lasers

Fiber laser systems are a rapidly progressing technology that may be useful as pump sources as well as direct ignition sources (cylinder-mounted or multiplexed). In addition to their potential for being power-efficient, compact, and inexpensive, the lasers inherently provide fiber delivery which can benefit versatile beam delivery and multiplexing. Pulsed systems can provide MW peak power and mJ energy pulses, i.e. parameters approaching those needed for laser ignition. Spark formation (in atmospheric pressure) air has been demonstrated with the focused output of a pulsed fiber laser [4

4. S. Joshi, A. P. Yalin, and A. Galvanauskas, “Use of hollow core fibers, fiber lasers, and photonic crystal fibers for spark delivery and laser ignition in gases,” Appl. Opt. 46(19), 4057–4064 (2007). [CrossRef] [PubMed]

]. These tests employed a multi-stage fiber amplifier system, seeded with electronically controlled nanosecond diode pulses, similar to the one described by Cheng et al. [66

66. M.-Y. Cheng, Y.-C. Chang, A. Galvanauskas, P. Mamidipudi, R. Changkakoti, and P. Gatchell, “High-energy and high-peak-power nanosecond pulse generation with beam quality control in 200-microm core highly multimode Yb-doped fiber amplifiers,” Opt. Lett. 30(4), 358–360 (2005). [CrossRef] [PubMed]

]; however, for spark formation, the last amplification stage used an 80-µm diameter core Yb-doped fiber yielding output beam quality of M2 ~1.5. The architecture does employ some free-space coupling and components. The combination of large core and high beam quality is highly advantageous for achieving spark-generation with nanosecond-long and few-mJ energy pulses. Laser-breakdown in atmospheric pressure air was achieved using 0.7 ns duration fiber laser pulses with 2.4 mJ pulse energy and 3.4 MW peak power at 50 Hz repetition rate. For practical ignition systems one must consider the prospects for elevated pulse energies. The energy extraction in a fiber laser is ultimately limited by the bulk damage intensity threshold in fused silica, which scales (approximately) inversely proportionally to the square root of pulse duration. This behavior indicates that higher pulse energies in the range of 1-10 + mJ may be achieved by increasing the pulse duration, while maintaining sufficient focused intensities for spark formation [4

4. S. Joshi, A. P. Yalin, and A. Galvanauskas, “Use of hollow core fibers, fiber lasers, and photonic crystal fibers for spark delivery and laser ignition in gases,” Appl. Opt. 46(19), 4057–4064 (2007). [CrossRef] [PubMed]

].

7. Conclusions

Direct fiber delivery of high power pulses to form combustion initiating sparks remains a technical challenge. This short review has summarized needed fiber output parameters and research results using several types of fibers. Coated hollow core fibers have been used to deliver sparks in atmospheric air and for engine ignition. The primary difference relative to (conventional) solid silica fibers is the improved beam quality at the fiber exit, though the utility of the hollow fibers is limited by their performance degradation (beam quality and energy) due to bending. Earlier results with MM step-index silica fibers did not allow reliably spark formation and combustion ignition since the beam quality at the fiber exit was generally inadequate to achieve the needed focused intensities. More recent results with large-clad fibers, which provide improved mode quality due to reduced mode coupling, are promising though additional research is needed to improve the versatility of the approach and to mitigate mounting-induced stress effects. Nonetheless, reliable sparking in atmospheric pressure air and engine ignition have been demonstrated. Photonic crystal fibers (and photonic bandgap fibers) are attractive owing to their single mode output though deliverable energy is often limiting. Kagome fibers show particularly promising results. The increased complexity of such fibers should be considered as it impacts cost and durability for practical use. Spark formation has been demonstrated at the output of fiber lasers and, owing to the inherent fiber coupling and high efficiency, they may provide attractive laser ignition sources.

Recent progress with compact lasers may make them favorable for ignition applications due to their performance and cost. On the other hand, multiplexed fiber solutions that minimize the number of lasers (or gain elements) remain of interest. Such systems may also be able to leverage the laser sources advances for use in the full multiplexed system. The findings from high power fiber delivery can also benefit other areas of optical technology such as laser machining and diagnostics. For example, coated hollow core fibers have been used for combustion diagnostics of harsh environments with Coherent Anti-Stokes Raman Spectroscopy (CARS) [67

67. J. M. Kriesel, N. Gat, and D. Plemmons, “Fiber optics for remote delivery of high power pulsed laser beams,” Proceedings of the 48th AIAA Aerospace Sciences Meeting, Orlando, FL, 2010.

]; similarly, the improved beam quality from large clad fibers has benefitted (ultraviolet) fiber delivered planar laser induced fluorescence (PLIF) [68

68. F. Loccisano, S. Joshi, I. S. Franka, Z. Y. Yin, W. R. Lempert, and A. P. Yalin, “Fiber-coupled ultraviolet planar laser-induced fluorescence for combustion diagnostics,” Appl. Opt. 51(27), 6691–6699 (2012). [CrossRef] [PubMed]

, 69

69. P. S. Hsu, W. D. Kulatilaka, S. Roy, and J. R. Gord, “Investigation of optical fibers for high-repetition-rate, ultraviolet planar laser-induced fluorescence of OH,” Appl. Opt. 52(13), 3108–3115 (2013). [CrossRef] [PubMed]

]. The present review has generally considered the use of non-resonant breakdown with nanosecond pulses. Of course, the use of other ignition schemes, for example involving thermal ignition, other wavelengths (resonant schemes), or multiple-pulse preionization [70

70. M. N. Shneider, A. M. Zheltikov, and R. B. Miles, “Tailoring the air plasma with a double laser pulse,” Phys. Plasmas 18(6), 063509 (2011). [CrossRef]

, 71

71. N. Wilvert, S. Joshi, and A. Yalin, “Ultraviolet laser plasma preionization and novel thomson scattering method for weakly ionized discharges,” in 51st AIAA Aerospace Sciences Meeting (Grapevine, TX, 2013).

], that relax the fiber delivery requirements may dramatically change the landscape of laser ignition hardware systems.

References and links

1.

D. Bradley, C. G. W. Sheppard, I. M. Suardjaja, and R. Woolley, “Fundamentals of high-energy spark ignition with lasers,” Combust. Flame 138(1-2), 55–77 (2004). [CrossRef]

2.

J. D. Dale, P. R. Smy, and R. M. Clements, “Laser ignited internal combustion engine - an experimental study,” SAE Paper 780329 (1979).

3.

H. Kopecek, S. Charareh, M. Lackner, C. Forsich, F. Winter, J. Klausner, G. Herdin, M. Weinrotter, and E. Wintner, “Laser ignition of methane-air mixtures at high pressures and diagnostics,” Journal of Engineering for Gas Turbines and Power-Transactions of the Asme 127(1), 213–219 (2005). [CrossRef]

4.

S. Joshi, A. P. Yalin, and A. Galvanauskas, “Use of hollow core fibers, fiber lasers, and photonic crystal fibers for spark delivery and laser ignition in gases,” Appl. Opt. 46(19), 4057–4064 (2007). [CrossRef] [PubMed]

5.

G. Lacaze, B. Cuenot, T. Poinsot, and M. Oschwald, “Large eddy simulation of laser ignition and compressible reacting flow in a rocket-like configuration,” Combust. Flame 156(6), 1166–1180 (2009). [CrossRef]

6.

A. M. Starik, N. S. Titova, L. V. Bezgin, and V. I. Kopchenov, “The promotion of ignition in a supersonic H-2-air mixing layer by laser-induced excitation of O-2 molecules: Numerical study,” Combust. Flame 156(8), 1641–1652 (2009). [CrossRef]

7.

G. Herdin, “GE Jenbacher`s update on laser ignited engines,” ICEF2006–1547, ASME ICE Fall Technical Conference, Sacramento, CA, 2006. [CrossRef]

8.

H. El-Rabii and G. Gaborel, “Laser ignition of flammable mixtures via a solid core optical fiber,” App. Phys. B-Lasers and Optics 87(1), 139–144 (2007). [CrossRef]

9.

H. El-Rabii, G. Gaborel, J. P. Lapios, D. Thevenin, J. C. Rolon, and J. P. Martin, “Laser spark ignition of two-phase monodisperse mixtures,” Opt. Commun. 256(4-6), 495–506 (2005). [CrossRef]

10.

M. Boileau, G. Staffelbach, B. Cuenot, T. Poinsot, and C. Berat, “LES of an ignition sequence in a gas turbine engine,” Combust. Flame 154(1-2), 2–22 (2008). [CrossRef]

11.

R. Oldenborg, J. Early, and C. Lester, “Advanced ignition and propulsion technology program,” (Los Alamos National Laboratory, 1998).

12.

A. H. Lefebvre, Gas Turbine Combustion (Taylor & Francis, 1999).

13.

T. Marchione, “Effectiveness of localized spark ignition in recirculating n-heptane spray flames,” in 21st ICDERS (Poitiers, France, 2007).

14.

H. Kofler, J. Tauer, G. Tartar, K. Iskra, J. Klausner, G. Herdin, and E. Wintner, “An innovative solid-state laser for engine ignition,” Laser Phys. Lett. 4(4), 322–327 (2007). [CrossRef]

15.

G. Kroupa, G. Franz, and E. Winkelhofer, “Novel miniaturized high-energy Nd-YAG laser for spark ignition in internal combustion engines,” Opt. Eng. 48(1), 014202 (2009). [CrossRef]

16.

N. Pavel, M. Tsunekane, K. Kanehara, and T. Taira, “Composite all-ceramics, passively Q-switched Nd:YAG/Cr4+:YAG monolithic micro-laser with two-beam output for multi-pointiIgnition,” in Conference on Lasers and Electro Optics, Baltimore, MD (2011).

17.

M. Tsunekane, T. Inohara, K. Kanehara, and T. Taira, “Micro-solid-state laser for ignition of automobile engines,” in Advances in Solid State Lasers Development and Applications, M. Grishin, ed. (InTech, 2010).

18.

D. L. McIntyre, S. D. Woodruff, and J. S. Ontko, “Lean-burn stationary natural gas reciprocating engine operation with a prototype fiber coupled diode end pumped passively q-switched laser spark plug” ICES2009–76013, ASME ICE Spring Technical Conference, Milwaukee, WI, (2009). [CrossRef]

19.

J. Tauer, H. Kofler, and E. Winter, “Laser-initiated ignition,” Laser & Photonics Reviews 4(1), 99–122 (2010). [CrossRef]

20.

D. Graham-Rowe and R. Won, “Lasers for engine ignition,” Nat. Photonics 2(9), 515–517 (2008). [CrossRef]

21.

A. P. Yalin, M. DeFoort, B. Willson, Y. Matsuura, and M. Miyagi, “Use of hollow-core fibers to deliver nanosecond Nd:YAG laser pulses to form sparks in gases,” Opt. Lett. 30(16), 2083–2085 (2005). [CrossRef] [PubMed]

22.

E. Schwarz, I. Muri, J. Tauer, H. Kofler, and E. Wintner, “Laser-induced ignition by optical breakdown,” Laser Phys. 20(6), 1545–1553 (2010). [CrossRef]

23.

A. Stakhiv, R. Gilber, H. Kopecek, A. M. Zheltikov, and E. Wintner, “Laser ignition of engines via optical fibers?” Laser Phys. 14, 738–747 (2004).

24.

J. Tauer, H. Kofler, E. Schwarz, and E. Wintner, “Transportation of megawatt millijoule laser pulses via optical fibers?” Central European Journal of Physics 8(2), 242–248 (2010). [CrossRef]

25.

A. P. Yalin, A. R. Reynolds, S. Joshi, M. W. Defoort, B. Willson, Y. Matsuura, and M. Miyagi, “Development of a fiber delivered laser ignition system for natural gas engines” (2006). ICEF2006–1574, ASME ICE Fall Technical Conference, Sacramento, CA, 2006. [CrossRef]

26.

B. Bihari, S. B. Gupta, R. R. Sekar, J. Gingrich, and J. Smith, “Development of advanced laser ignition system for stationary natural gas reciprocating engines,” ICEF2005–1325, ASME ICE Fall Technical Conference, Ottawa, Canada, (2005). [CrossRef]

27.

A. Sircar, R. K. Dwivedi, and R. K. Thareja, “Laser induced breakdown of Ar, N-2 and O-2 gases using 1.064, 0.532, 0.355 and 0.266 μm m radiation,” App. Phys. B-Lasers and Optics 63, 623–627 (1996).

28.

T. X. Phuoc, “Laser spark ignition: experimental determination of laser-induced breakdown thresholds of combustion gases,” Opt. Commun. 175(4-6), 419–423 (2000). [CrossRef]

29.

W. F. Hsieh, J. H. Eickmans, and R. K. Chang, “Internal and external laser-induced avalanche breakdown of single droplets in an argon atmosphere,” JOSA B-Optical Physics 4(11), 1816–1820 (1987). [CrossRef]

30.

R. G. Pinnick, P. Chylek, M. Jarzembski, E. Creegan, V. Srivastava, G. Fernandez, J. D. Pendleton, and A. Biswas, “Aerosol-induced laser breakdown thresholds - wavelength dependence,” Appl. Opt. 27(5), 987–996 (1988). [CrossRef] [PubMed]

31.

B. Richou, I. Schertz, I. Gobin, and J. Richou, “Delivery of 10-MW Nd:YAG laser pulses by large-core optical fibers: Dependence of the laser-intensity profile on beam propagation,” Appl. Opt. 36(7), 1610–1614 (1997). [CrossRef] [PubMed]

32.

T. Schmidt-Uhlig, P. Karlitschek, G. Marowsky, and Y. Sano, “New simplified coupling scheme for the delivery of 20 MW Nd:YAG laser pulses by large core optical fibers,” Appl. Phys. B 72(2), 183–186 (2001). [CrossRef]

33.

A. V. Smith and B. T. Do, “Bulk and surface laser damage of silica by picosecond and nanosecond pulses at 1064 nm,” Appl. Opt. 47(26), 4812–4832 (2008). [CrossRef] [PubMed]

34.

A. E. Siegman, “Defining, measuring, and optimizing laser-beam quality,” in Laser Resonators and Coherent Optics: Modeling, Technology, and Applications, A. Bhowmik, ed. (SPIE - Int Soc Optical Engineering, 1993), pp. 2–12.

35.

H. Kopecek, H. Maier, G. Reider, F. Winter, and E. Wintner, “Laser ignition of methane-air mixtures at high pressures,” Exp. Therm. Fluid Sci. 27(4), 499–503 (2003). [CrossRef]

36.

H. El-Rabii, G. Gaborel, J. P. Lapios, D. Thévenin, J. C. Rolon, and J. P. Martin, “Laser spark ignition of two-phase monodisperse mixtures,” Opt. Commun. 256(4-6), 495–506 (2005). [CrossRef]

37.

G. C. Gebel, T. Mosbach, W. Meier, and M. Aigner, “Laser-induced ignition of kerosene in a model combustor,” in Proceedings of the European Combustion Meeting0612011.

38.

C. Letty, E. Mastorakos, A. R. Masri, M. Juddoo, and W. O'Loughlin, “Structure of igniting ethanol and n-heptane spray flames with and without swirl,” Exp. Therm. Fluid Sci. 43, 47–54 (2012). [CrossRef]

39.

G. C. Gebel, T. Mosbach, W. Meier, and M. Aigner, “An experimental investigation of kerosene droplet breakup by laser-induced blast waves,” in Proceedings of ASME Turbo Expo 2012021505 (Coopenhagen, Denmark, 2012). [CrossRef]

40.

T. X. Phuoc, “A comparative study of the photon pressure force, the photophoretic force, and the adhesion van der Waals force,” Opt. Commun. 245(1-6), 27–35 (2005). [CrossRef]

41.

Y. Matsuura, A. Tsuchiuchi, H. Noguchi, and M. Miyagi, “Hollow fiber optics with improved durability for high-peak-power pulses of Q-switched Nd:YAG lasers,” Appl. Opt. 46(8), 1279–1282 (2007). [CrossRef] [PubMed]

42.

Y. Matsuura, G. Takada, T. Yamamoto, Y. W. Shi, and M. Miyagi, “Hollow fibers for delivery of harmonic pulses of Q-switched Nd:YAG lasers,” Appl. Opt. 41(3), 442–445 (2002). [CrossRef] [PubMed]

43.

J. P. Parry, T. J. Stephens, J. D. Shephard, J. D. C. Jones, and D. P. Hand, “Analysis of optical damage mechanisms in hollow-core waveguides delivering nanosecond pulses from a Q-switched Nd:YAG laser,” Appl. Opt. 45(36), 9160–9167 (2006). [CrossRef] [PubMed]

44.

A. P. Yalin, M. W. Defoort, S. Joshi, D. Olsen, B. Willson, Y. Matsuura, and M. Miyagi, “Laser ignition of natural gas engines using fiber delivery,” ICEF2005–1336, ASME ICE Fall Technical Conference, Ottawa, Canada, (2005). [CrossRef]

45.

R. K. Nubling and J. A. Harrington, “Launch conditions and mode coupling in hollow-glass waveguides,” Opt. Eng. 37(9), 2454–2458 (1998). [CrossRef]

46.

B. Bihari, S. B. Gupta, R. R. Sekar, J. Gingrich, and J. Smith, “Development of advanced laser ignition system for stationary natural gas reciprocating engines,” ICEF2005–1325, ASME ICE Fall Technical Conference, Ottawa, Canada,(2005). [CrossRef]

47.

J. D. Mullett, G. Dearden, R. Dodd, A. T. Shenton, G. Triantos, and K. G. Watkins, “A comparative study of optical fiber types for application in a laser-induced ignition system ,” J. Opt. A: Pure Appl. Opt. 11, 054007 (2009).

48.

M. Biruduganti, S. Gupta, B. Bihari, G. Klett, and R. Sekar, “Performance analysis of a natural gas generator using laser ignition,” ICEF2004–983, ASME ICE Fall Technical Conference, Long Beach, California, 2004. [CrossRef]

49.

S. Joshi, N. Wilvert, and A. P. Yalin, “Delivery of high intensity beams with large clad step-index fibers for engine ignition,” App. Phys. B-Lasers and Optics 108(4), 925–932 (2012). [CrossRef]

50.

S. Hurand, L. A. Chauny, H. El-Rabii, S. Joshi, and A. P. Yalin, “Mode coupling and output beam quality of 100-400 μm core silica fibers,” Appl. Opt. 50(4), 492–499 (2011). [CrossRef] [PubMed]

51.

N. Wilvert, S. Joshi, and A. Yalin, “On comparative engine performance testing with fiber delivered laser ignition and electrical ignition,” ICEF2012–92007, ASME ICE Fall Technical Conference, Vancouver, Canada, (2012). [CrossRef]

52.

A. K. Ghatak and K. Thyagarajan, Optical Electronics (Cambridge University Press, 1989).

53.

D. Gloge, “Optical power flow in multimode fibers,” Bell Syst. Tech. J. 51(8), 1767–1783 (1972). [CrossRef]

54.

M. E. Fermann, “Single-mode excitation of multimode fibers with ultrashort pulses,” Opt. Lett. 23(1), 52–54 (1998). [CrossRef] [PubMed]

55.

S. Joshi, “Fiber delivery and diagnostics of laser spark ignition for natural gas engines,” PhD Thesis, Colorado State University, (2008).

56.

N. Wilvert, “Development and testing of a solid core fiber optic delivery system and ultraviolet preionization for laser ignition,” MSc Thesis, Colorado State University, (2012).

57.

A. Bjarklev, J. Broeng, and A.-S. Bjarklev, Photonic Crystal Fibers (Springer, 2003).

58.

J. D. Shephard, F. Couny, P. S. J. Russell, J. D. C. Jones, J. C. Knight, and D. P. Hand, “Improved hollow-core photonic crystal fiber design for delivery of nanosecond pulses in laser micromachining applications,” Appl. Opt. 44(21), 4582–4588 (2005). [CrossRef] [PubMed]

59.

J. Tauer, F. Orban, H. Kofler, A. B. Fedotov, I. V. Fedotov, V. P. Mitrokhin, A. M. Zheltikov, and E. Wintner, “High-throughput of single high-power laser pulses by hollow photonic band gap fibers,” Laser Phys. Lett. 4(6), 444–448 (2007). [CrossRef]

60.

S. O. Konorov, A. B. Fedotov, O. A. Kolevatova, V. I. Beloglazov, N. B. Skibina, A. V. Shcherbakov, E. Wintner, and A. M. Zheltikov, “Laser breakdown with millijoule trains of picosecond pulses transmitted through a hollow-core photonic-crystal fibre,” J. Phys. D Appl. Phys. 36(12), 1375–1381 (2003). [CrossRef]

61.

D. M. T. L. Michaille, C. R. Bennett, T. J. Shephard, C. Jacobsen, and T. P. Hansen, “Damage threshold and bending properties of photonic crystal and photonic bandgap optical fibers,” presented at the Proc. SPIE 5618 (2004). [CrossRef]

62.

A. H. Al-Janabi, “Transportation of nanosecond laser pulses by hollow core photonic crystal fiber for laser ignition,” Laser Phys. Lett. 2(11), 529–531 (2005). [CrossRef]

63.

C. D. Brooks and F. Di Teodoro, “Multimegawatt peak-power, single-transverse-mode operation of a 100 μm core diameter, Yb-doped rodlike photonic crystal fiber amplifier ,” App. Phys. Lett . 89111119 (2006).

64.

Z. Ruff, D. Shemuly, X. A. Peng, O. Shapira, Z. Wang, and Y. Fink, “Polymer-composite fibers for transmitting high peak power pulses at 1.55 microns,” Opt. Express 18(15), 15697–15703 (2010). [CrossRef] [PubMed]

65.

B. Beaudou, F. Gerôme, Y. Y. Wang, M. Alharbi, T. D. Bradley, G. Humbert, J. L. Auguste, J. M. Blondy, and F. Benabid, “Millijoule laser pulse delivery for spark ignition through kagome hollow-core fiber,” Opt. Lett. 37(9), 1430–1432 (2012). [CrossRef] [PubMed]

66.

M.-Y. Cheng, Y.-C. Chang, A. Galvanauskas, P. Mamidipudi, R. Changkakoti, and P. Gatchell, “High-energy and high-peak-power nanosecond pulse generation with beam quality control in 200-microm core highly multimode Yb-doped fiber amplifiers,” Opt. Lett. 30(4), 358–360 (2005). [CrossRef] [PubMed]

67.

J. M. Kriesel, N. Gat, and D. Plemmons, “Fiber optics for remote delivery of high power pulsed laser beams,” Proceedings of the 48th AIAA Aerospace Sciences Meeting, Orlando, FL, 2010.

68.

F. Loccisano, S. Joshi, I. S. Franka, Z. Y. Yin, W. R. Lempert, and A. P. Yalin, “Fiber-coupled ultraviolet planar laser-induced fluorescence for combustion diagnostics,” Appl. Opt. 51(27), 6691–6699 (2012). [CrossRef] [PubMed]

69.

P. S. Hsu, W. D. Kulatilaka, S. Roy, and J. R. Gord, “Investigation of optical fibers for high-repetition-rate, ultraviolet planar laser-induced fluorescence of OH,” Appl. Opt. 52(13), 3108–3115 (2013). [CrossRef] [PubMed]

70.

M. N. Shneider, A. M. Zheltikov, and R. B. Miles, “Tailoring the air plasma with a double laser pulse,” Phys. Plasmas 18(6), 063509 (2011). [CrossRef]

71.

N. Wilvert, S. Joshi, and A. Yalin, “Ultraviolet laser plasma preionization and novel thomson scattering method for weakly ionized discharges,” in 51st AIAA Aerospace Sciences Meeting (Grapevine, TX, 2013).

OCIS Codes
(060.2270) Fiber optics and optical communications : Fiber characterization
(060.2310) Fiber optics and optical communications : Fiber optics
(060.2400) Fiber optics and optical communications : Fiber properties
(060.4005) Fiber optics and optical communications : Microstructured fibers

History
Original Manuscript: August 2, 2013
Revised Manuscript: September 5, 2013
Manuscript Accepted: September 6, 2013
Published: November 4, 2013

Virtual Issues
Laser Ignition (2013) Optics Express

Citation
Azer P. Yalin, "High power fiber delivery for laser ignition applications," Opt. Express 21, A1102-A1112 (2013)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-21-S6-A1102


Sort:  Author  |  Year  |  Journal  |  Reset  

References

  1. D. Bradley, C. G. W. Sheppard, I. M. Suardjaja, and R. Woolley, “Fundamentals of high-energy spark ignition with lasers,” Combust. Flame138(1-2), 55–77 (2004). [CrossRef]
  2. J. D. Dale, P. R. Smy, and R. M. Clements, “Laser ignited internal combustion engine - an experimental study,” SAE Paper 780329 (1979).
  3. H. Kopecek, S. Charareh, M. Lackner, C. Forsich, F. Winter, J. Klausner, G. Herdin, M. Weinrotter, and E. Wintner, “Laser ignition of methane-air mixtures at high pressures and diagnostics,” Journal of Engineering for Gas Turbines and Power-Transactions of the Asme127(1), 213–219 (2005). [CrossRef]
  4. S. Joshi, A. P. Yalin, and A. Galvanauskas, “Use of hollow core fibers, fiber lasers, and photonic crystal fibers for spark delivery and laser ignition in gases,” Appl. Opt.46(19), 4057–4064 (2007). [CrossRef] [PubMed]
  5. G. Lacaze, B. Cuenot, T. Poinsot, and M. Oschwald, “Large eddy simulation of laser ignition and compressible reacting flow in a rocket-like configuration,” Combust. Flame156(6), 1166–1180 (2009). [CrossRef]
  6. A. M. Starik, N. S. Titova, L. V. Bezgin, and V. I. Kopchenov, “The promotion of ignition in a supersonic H-2-air mixing layer by laser-induced excitation of O-2 molecules: Numerical study,” Combust. Flame156(8), 1641–1652 (2009). [CrossRef]
  7. G. Herdin, “GE Jenbacher`s update on laser ignited engines,” ICEF2006–1547, ASME ICE Fall Technical Conference, Sacramento, CA, 2006. [CrossRef]
  8. H. El-Rabii and G. Gaborel, “Laser ignition of flammable mixtures via a solid core optical fiber,” App. Phys. B-Lasers and Optics87(1), 139–144 (2007). [CrossRef]
  9. H. El-Rabii, G. Gaborel, J. P. Lapios, D. Thevenin, J. C. Rolon, and J. P. Martin, “Laser spark ignition of two-phase monodisperse mixtures,” Opt. Commun.256(4-6), 495–506 (2005). [CrossRef]
  10. M. Boileau, G. Staffelbach, B. Cuenot, T. Poinsot, and C. Berat, “LES of an ignition sequence in a gas turbine engine,” Combust. Flame154(1-2), 2–22 (2008). [CrossRef]
  11. R. Oldenborg, J. Early, and C. Lester, “Advanced ignition and propulsion technology program,” (Los Alamos National Laboratory, 1998).
  12. A. H. Lefebvre, Gas Turbine Combustion (Taylor & Francis, 1999).
  13. T. Marchione, “Effectiveness of localized spark ignition in recirculating n-heptane spray flames,” in 21st ICDERS (Poitiers, France, 2007).
  14. H. Kofler, J. Tauer, G. Tartar, K. Iskra, J. Klausner, G. Herdin, and E. Wintner, “An innovative solid-state laser for engine ignition,” Laser Phys. Lett.4(4), 322–327 (2007). [CrossRef]
  15. G. Kroupa, G. Franz, and E. Winkelhofer, “Novel miniaturized high-energy Nd-YAG laser for spark ignition in internal combustion engines,” Opt. Eng.48(1), 014202 (2009). [CrossRef]
  16. N. Pavel, M. Tsunekane, K. Kanehara, and T. Taira, “Composite all-ceramics, passively Q-switched Nd:YAG/Cr4+:YAG monolithic micro-laser with two-beam output for multi-pointiIgnition,” in Conference on Lasers and Electro Optics, Baltimore, MD (2011).
  17. M. Tsunekane, T. Inohara, K. Kanehara, and T. Taira, “Micro-solid-state laser for ignition of automobile engines,” in Advances in Solid State Lasers Development and Applications, M. Grishin, ed. (InTech, 2010).
  18. D. L. McIntyre, S. D. Woodruff, and J. S. Ontko, “Lean-burn stationary natural gas reciprocating engine operation with a prototype fiber coupled diode end pumped passively q-switched laser spark plug” ICES2009–76013, ASME ICE Spring Technical Conference, Milwaukee, WI, (2009). [CrossRef]
  19. J. Tauer, H. Kofler, and E. Winter, “Laser-initiated ignition,” Laser & Photonics Reviews4(1), 99–122 (2010). [CrossRef]
  20. D. Graham-Rowe and R. Won, “Lasers for engine ignition,” Nat. Photonics2(9), 515–517 (2008). [CrossRef]
  21. A. P. Yalin, M. DeFoort, B. Willson, Y. Matsuura, and M. Miyagi, “Use of hollow-core fibers to deliver nanosecond Nd:YAG laser pulses to form sparks in gases,” Opt. Lett.30(16), 2083–2085 (2005). [CrossRef] [PubMed]
  22. E. Schwarz, I. Muri, J. Tauer, H. Kofler, and E. Wintner, “Laser-induced ignition by optical breakdown,” Laser Phys.20(6), 1545–1553 (2010). [CrossRef]
  23. A. Stakhiv, R. Gilber, H. Kopecek, A. M. Zheltikov, and E. Wintner, “Laser ignition of engines via optical fibers?” Laser Phys.14, 738–747 (2004).
  24. J. Tauer, H. Kofler, E. Schwarz, and E. Wintner, “Transportation of megawatt millijoule laser pulses via optical fibers?” Central European Journal of Physics8(2), 242–248 (2010). [CrossRef]
  25. A. P. Yalin, A. R. Reynolds, S. Joshi, M. W. Defoort, B. Willson, Y. Matsuura, and M. Miyagi, “Development of a fiber delivered laser ignition system for natural gas engines” (2006). ICEF2006–1574, ASME ICE Fall Technical Conference, Sacramento, CA, 2006. [CrossRef]
  26. B. Bihari, S. B. Gupta, R. R. Sekar, J. Gingrich, and J. Smith, “Development of advanced laser ignition system for stationary natural gas reciprocating engines,” ICEF2005–1325, ASME ICE Fall Technical Conference, Ottawa, Canada, (2005). [CrossRef]
  27. A. Sircar, R. K. Dwivedi, and R. K. Thareja, “Laser induced breakdown of Ar, N-2 and O-2 gases using 1.064, 0.532, 0.355 and 0.266 μm m radiation,” App. Phys. B-Lasers and Optics63, 623–627 (1996).
  28. T. X. Phuoc, “Laser spark ignition: experimental determination of laser-induced breakdown thresholds of combustion gases,” Opt. Commun.175(4-6), 419–423 (2000). [CrossRef]
  29. W. F. Hsieh, J. H. Eickmans, and R. K. Chang, “Internal and external laser-induced avalanche breakdown of single droplets in an argon atmosphere,” JOSA B-Optical Physics4(11), 1816–1820 (1987). [CrossRef]
  30. R. G. Pinnick, P. Chylek, M. Jarzembski, E. Creegan, V. Srivastava, G. Fernandez, J. D. Pendleton, and A. Biswas, “Aerosol-induced laser breakdown thresholds - wavelength dependence,” Appl. Opt.27(5), 987–996 (1988). [CrossRef] [PubMed]
  31. B. Richou, I. Schertz, I. Gobin, and J. Richou, “Delivery of 10-MW Nd:YAG laser pulses by large-core optical fibers: Dependence of the laser-intensity profile on beam propagation,” Appl. Opt.36(7), 1610–1614 (1997). [CrossRef] [PubMed]
  32. T. Schmidt-Uhlig, P. Karlitschek, G. Marowsky, and Y. Sano, “New simplified coupling scheme for the delivery of 20 MW Nd:YAG laser pulses by large core optical fibers,” Appl. Phys. B72(2), 183–186 (2001). [CrossRef]
  33. A. V. Smith and B. T. Do, “Bulk and surface laser damage of silica by picosecond and nanosecond pulses at 1064 nm,” Appl. Opt.47(26), 4812–4832 (2008). [CrossRef] [PubMed]
  34. A. E. Siegman, “Defining, measuring, and optimizing laser-beam quality,” in Laser Resonators and Coherent Optics: Modeling, Technology, and Applications, A. Bhowmik, ed. (SPIE - Int Soc Optical Engineering, 1993), pp. 2–12.
  35. H. Kopecek, H. Maier, G. Reider, F. Winter, and E. Wintner, “Laser ignition of methane-air mixtures at high pressures,” Exp. Therm. Fluid Sci.27(4), 499–503 (2003). [CrossRef]
  36. H. El-Rabii, G. Gaborel, J. P. Lapios, D. Thévenin, J. C. Rolon, and J. P. Martin, “Laser spark ignition of two-phase monodisperse mixtures,” Opt. Commun.256(4-6), 495–506 (2005). [CrossRef]
  37. G. C. Gebel, T. Mosbach, W. Meier, and M. Aigner, “Laser-induced ignition of kerosene in a model combustor,” in Proceedings of the European Combustion Meeting0612011.
  38. C. Letty, E. Mastorakos, A. R. Masri, M. Juddoo, and W. O'Loughlin, “Structure of igniting ethanol and n-heptane spray flames with and without swirl,” Exp. Therm. Fluid Sci.43, 47–54 (2012). [CrossRef]
  39. G. C. Gebel, T. Mosbach, W. Meier, and M. Aigner, “An experimental investigation of kerosene droplet breakup by laser-induced blast waves,” in Proceedings of ASME Turbo Expo 2012021505 (Coopenhagen, Denmark, 2012). [CrossRef]
  40. T. X. Phuoc, “A comparative study of the photon pressure force, the photophoretic force, and the adhesion van der Waals force,” Opt. Commun.245(1-6), 27–35 (2005). [CrossRef]
  41. Y. Matsuura, A. Tsuchiuchi, H. Noguchi, and M. Miyagi, “Hollow fiber optics with improved durability for high-peak-power pulses of Q-switched Nd:YAG lasers,” Appl. Opt.46(8), 1279–1282 (2007). [CrossRef] [PubMed]
  42. Y. Matsuura, G. Takada, T. Yamamoto, Y. W. Shi, and M. Miyagi, “Hollow fibers for delivery of harmonic pulses of Q-switched Nd:YAG lasers,” Appl. Opt.41(3), 442–445 (2002). [CrossRef] [PubMed]
  43. J. P. Parry, T. J. Stephens, J. D. Shephard, J. D. C. Jones, and D. P. Hand, “Analysis of optical damage mechanisms in hollow-core waveguides delivering nanosecond pulses from a Q-switched Nd:YAG laser,” Appl. Opt.45(36), 9160–9167 (2006). [CrossRef] [PubMed]
  44. A. P. Yalin, M. W. Defoort, S. Joshi, D. Olsen, B. Willson, Y. Matsuura, and M. Miyagi, “Laser ignition of natural gas engines using fiber delivery,” ICEF2005–1336, ASME ICE Fall Technical Conference, Ottawa, Canada, (2005). [CrossRef]
  45. R. K. Nubling and J. A. Harrington, “Launch conditions and mode coupling in hollow-glass waveguides,” Opt. Eng.37(9), 2454–2458 (1998). [CrossRef]
  46. B. Bihari, S. B. Gupta, R. R. Sekar, J. Gingrich, and J. Smith, “Development of advanced laser ignition system for stationary natural gas reciprocating engines,” ICEF2005–1325, ASME ICE Fall Technical Conference, Ottawa, Canada,(2005). [CrossRef]
  47. J. D. Mullett, G. Dearden, R. Dodd, A. T. Shenton, G. Triantos, and K. G. Watkins, “A comparative study of optical fiber types for application in a laser-induced ignition system,” J. Opt. A: Pure Appl. Opt. 11, 054007 (2009).
  48. M. Biruduganti, S. Gupta, B. Bihari, G. Klett, and R. Sekar, “Performance analysis of a natural gas generator using laser ignition,” ICEF2004–983, ASME ICE Fall Technical Conference, Long Beach, California, 2004. [CrossRef]
  49. S. Joshi, N. Wilvert, and A. P. Yalin, “Delivery of high intensity beams with large clad step-index fibers for engine ignition,” App. Phys. B-Lasers and Optics108(4), 925–932 (2012). [CrossRef]
  50. S. Hurand, L. A. Chauny, H. El-Rabii, S. Joshi, and A. P. Yalin, “Mode coupling and output beam quality of 100-400 μm core silica fibers,” Appl. Opt.50(4), 492–499 (2011). [CrossRef] [PubMed]
  51. N. Wilvert, S. Joshi, and A. Yalin, “On comparative engine performance testing with fiber delivered laser ignition and electrical ignition,” ICEF2012–92007, ASME ICE Fall Technical Conference, Vancouver, Canada, (2012). [CrossRef]
  52. A. K. Ghatak and K. Thyagarajan, Optical Electronics (Cambridge University Press, 1989).
  53. D. Gloge, “Optical power flow in multimode fibers,” Bell Syst. Tech. J.51(8), 1767–1783 (1972). [CrossRef]
  54. M. E. Fermann, “Single-mode excitation of multimode fibers with ultrashort pulses,” Opt. Lett.23(1), 52–54 (1998). [CrossRef] [PubMed]
  55. S. Joshi, “Fiber delivery and diagnostics of laser spark ignition for natural gas engines,” PhD Thesis, Colorado State University, (2008).
  56. N. Wilvert, “Development and testing of a solid core fiber optic delivery system and ultraviolet preionization for laser ignition,” MSc Thesis, Colorado State University, (2012).
  57. A. Bjarklev, J. Broeng, and A.-S. Bjarklev, Photonic Crystal Fibers (Springer, 2003).
  58. J. D. Shephard, F. Couny, P. S. J. Russell, J. D. C. Jones, J. C. Knight, and D. P. Hand, “Improved hollow-core photonic crystal fiber design for delivery of nanosecond pulses in laser micromachining applications,” Appl. Opt.44(21), 4582–4588 (2005). [CrossRef] [PubMed]
  59. J. Tauer, F. Orban, H. Kofler, A. B. Fedotov, I. V. Fedotov, V. P. Mitrokhin, A. M. Zheltikov, and E. Wintner, “High-throughput of single high-power laser pulses by hollow photonic band gap fibers,” Laser Phys. Lett.4(6), 444–448 (2007). [CrossRef]
  60. S. O. Konorov, A. B. Fedotov, O. A. Kolevatova, V. I. Beloglazov, N. B. Skibina, A. V. Shcherbakov, E. Wintner, and A. M. Zheltikov, “Laser breakdown with millijoule trains of picosecond pulses transmitted through a hollow-core photonic-crystal fibre,” J. Phys. D Appl. Phys.36(12), 1375–1381 (2003). [CrossRef]
  61. D. M. T. L. Michaille, C. R. Bennett, T. J. Shephard, C. Jacobsen, and T. P. Hansen, “Damage threshold and bending properties of photonic crystal and photonic bandgap optical fibers,” presented at the Proc. SPIE 5618 (2004). [CrossRef]
  62. A. H. Al-Janabi, “Transportation of nanosecond laser pulses by hollow core photonic crystal fiber for laser ignition,” Laser Phys. Lett.2(11), 529–531 (2005). [CrossRef]
  63. C. D. Brooks and F. Di Teodoro, “Multimegawatt peak-power, single-transverse-mode operation of a 100 μm core diameter, Yb-doped rodlike photonic crystal fiber amplifier,” App. Phys. Lett. 89111119 (2006).
  64. Z. Ruff, D. Shemuly, X. A. Peng, O. Shapira, Z. Wang, and Y. Fink, “Polymer-composite fibers for transmitting high peak power pulses at 1.55 microns,” Opt. Express18(15), 15697–15703 (2010). [CrossRef] [PubMed]
  65. B. Beaudou, F. Gerôme, Y. Y. Wang, M. Alharbi, T. D. Bradley, G. Humbert, J. L. Auguste, J. M. Blondy, and F. Benabid, “Millijoule laser pulse delivery for spark ignition through kagome hollow-core fiber,” Opt. Lett.37(9), 1430–1432 (2012). [CrossRef] [PubMed]
  66. M.-Y. Cheng, Y.-C. Chang, A. Galvanauskas, P. Mamidipudi, R. Changkakoti, and P. Gatchell, “High-energy and high-peak-power nanosecond pulse generation with beam quality control in 200-microm core highly multimode Yb-doped fiber amplifiers,” Opt. Lett.30(4), 358–360 (2005). [CrossRef] [PubMed]
  67. J. M. Kriesel, N. Gat, and D. Plemmons, “Fiber optics for remote delivery of high power pulsed laser beams,” Proceedings of the 48th AIAA Aerospace Sciences Meeting, Orlando, FL, 2010.
  68. F. Loccisano, S. Joshi, I. S. Franka, Z. Y. Yin, W. R. Lempert, and A. P. Yalin, “Fiber-coupled ultraviolet planar laser-induced fluorescence for combustion diagnostics,” Appl. Opt.51(27), 6691–6699 (2012). [CrossRef] [PubMed]
  69. P. S. Hsu, W. D. Kulatilaka, S. Roy, and J. R. Gord, “Investigation of optical fibers for high-repetition-rate, ultraviolet planar laser-induced fluorescence of OH,” Appl. Opt.52(13), 3108–3115 (2013). [CrossRef] [PubMed]
  70. M. N. Shneider, A. M. Zheltikov, and R. B. Miles, “Tailoring the air plasma with a double laser pulse,” Phys. Plasmas18(6), 063509 (2011). [CrossRef]
  71. N. Wilvert, S. Joshi, and A. Yalin, “Ultraviolet laser plasma preionization and novel thomson scattering method for weakly ionized discharges,” in 51st AIAA Aerospace Sciences Meeting (Grapevine, TX, 2013).

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.


« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited