Broadband single-pulse CARS spectra in a fired internal combustion engine

Klick, David; Marko, Kenneth A.; Rimai, L.

doi:10.1364/ao.20.001178

Cited by 99 publications

(21 citation statements)

References 7 publications

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“…The first thermometry applications have been demonstrated some 30 years ago by Stenhouse [291] and Klick [292]. More recently Ewart et al [293] studied the influence of the fuel on the burnt gas temperature and compared their experimental results with predictions from a multizone computer simulation.…”

Section: Multi-species and Multiplex Measurementsmentioning

confidence: 99%

Laser diagnostics and minor species detection in combustion using resonant four-wave mixing

Kiefer

Ewart

2011

Progress in Energy and Combustion Science

129

112

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Laser-based methods have transformed combustion diagnostics in the past few decades. The high intensity, coherence, high spectral resolution and frequency tunability available from laser radiation has provided powerful tools for studying microscopic processes and macroscopic phenomena in combustion by linear and nonlinear optical processes. This review focuses on nonlinear optical techniques based on resonant four-wave mixing for non-intrusive measurements of minor species in combustion. The importance of minor species such as reaction intermediates is outlined together with the challenges they present for detection and measurement in the hostile environments of flames, technical combustors, and engines. The limitations of conventional optical methods for such measurements are described and the particular advantages of coherent methods using nonlinear optical techniques are discussed.The basic physics underlying four-wave wave mixing processes and theoretical models for signal calculation are then presented together with a discussion of how combustion parameters may be derived from analysis of signals generated in various four-wave mixing processes. The most important four-wave mixing processes, in this context, are then reviewed:Degenerate Four-Wave Mixing (DFWM), Coherent Anti-Stokes Raman Scattering (CARS), Laser Induced Grating Spectroscopy (LIGS) and Polarization Spectroscopy (PS). In each case the fundamental physics is outlined to explain the particular properties and diagnostic advantages of each technique. The application of the methods mentioned to molecular physics studies of combustion species is then reviewed along with their application in measurement of concentration, temperature and other combustion parameters. Related nonlinear techniques and recent extensions to the ultra-fast regime are briefly reviewed. Finally practical considerations relevant to multi-dimensional and multi-species measurements, as well as applications in technical combustion systems are discussed.Keywords: nonlinear optical spectroscopy, four-wave mixing, combustion diagnostics, minor species detection, laser-induced gratings, polarization spectroscopy IntroductionEnergy from renewable sources such as solar and wind power is the goal of much current research and technological development. Combustion, however, is and is likely to remain for the foreseeable future, the most important energy source for heat, electrical power and especially for transportation. In technical combustion systems the chemical energy of fossil fuels such as coal, crude oil and natural gas is converted into heat through oxidation with oxygen from air. However, fossil fuel resources are limited and alternatives like biofuels [1] or novel technologies such as fuel cells [2] are not yet able to meet the demand. Consequently, for a sustainable use of fossil fuels it is desirable to further improve the efficiency, maintainability and reliability of existing combustion devices. Achieving such improvements depends upon an improved understanding of t...

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Section: Multi-species and Multiplex Measurementsmentioning

confidence: 99%

Laser diagnostics and minor species detection in combustion using resonant four-wave mixing

Kiefer

Ewart

2011

Progress in Energy and Combustion Science

129

112

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“…Probing of vibrational-rotational state populations using CARS, normally referred to as vibrational CARS, has been used in numerous applications including several real-world situations (see, e.g., Refs. [6][7][8][9].…”

Section: Introductionmentioning

confidence: 99%

Rotational CARS: a comparison of different techniques with emphasis on accuracy in temperature determination

Aldén¹,

Bengtsson²,

Edner³

et al. 1989

Appl. Opt.

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Different rotational CARS techniques have been evaluated in terms of single-shot temperature accuracy and signal intensity in room temperature nitrogen and in flames. The different techniques include both dual broadband techniques, using one or two broadband dye lasers, and conventional rotational CARS with different dye lasers. These techniques are also compared with vibrational CARS concerning temperature accuracy and with theoretical predictions. The results indicate that the dual broadband techniques are to be preferred over conventional rotational CARS and also over vibrational CARS at room temperature. At flame temperatures the vibrational CARS technique seems to be the technique yielding highest temperature accuracy. The experimental results are also generally in good agreement with the calculated values.

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“…9). Even higher transitions, such as J=9~J= 11 which coincides with the fundamental, vibrational CARS mode of carbonmonoxide at 2131cm -1 are unavailable under room temperature conditions but have been recently observed in connection with combustion studies [5]. Table 2 summarizes limits of detection obtained for H z using the rotational The first row refers to single-shot spectra with subtraction of the background due to electrical noise of the diode-array camera and due to scattering light in the detection system.…”

Section: Resultsmentioning

confidence: 99%

“…Use of pure rotational transitions, however, has been made so far only in a few applications dealing with concentration and temperature measurements of small molecules, such as Hz, N2, 02, N20, and CO [2][3][4][5][6][7][8][9][10][11][12]. It is the purpose of this paper to demonstrate that pure rotational CARS spectroscopy in the vibronic groundstate of molecular hydrogen is a very powerful tool for the detection of small concentrations of H2, which can be utilized effectively for temperature measurements in various temperature ranges.…”

Section: Pacs: 4265mentioning

confidence: 99%

Experimental study of vibrational and pure rotational coherent anti-stokes Raman scattering (CARS) in molecular hydrogen

et al. 1986

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Abstract. Using a specially designed excimer-laser-pumped dye laser of adjustable bandwidth high-lying pure rotational transitions of both, ortho-and para-hydrogen have been identified by coherent anti-Stokes Raman scattering (CARS). As an interesting application Hz-based CARS-thermometry is discussed. PACS: 42.65Coherent anti-Stokes Raman spectroscopy (CARS) using rotational-vibrational transitions has proven to be a powerful tool in various areas of science and technology since its first demonstration by Maker and Terhune [1]. Use of pure rotational transitions, however, has been made so far only in a few applications dealing with concentration and temperature measurements of small molecules, such as Hz, N2, 02, N20, and CO [2][3][4][5][6][7][8][9][10][11][12]. It is the purpose of this paper to demonstrate that pure rotational CARS spectroscopy in the vibronic groundstate of molecular hydrogen is a very powerful tool for the detection of small concentrations of H2, which can be utilized effectively for temperature measurements in various temperature ranges. The principal difference in terms of energy levels used for rotational and vibrational CARS of hydrogen can be explained with reference to Fig. 1, showing the typical scattering processes taking place in a CARStype experiment. The striking difference between vibrational and rotational CARS is the energy difference between the respective resonantly excited real levels, such as AEvi b for the v=0~v= 1 transition and AEro t for the J = 1 --*J = 3 transition, which turned out to be the most intense rotational transition for H 2 trace analysis under room temperature conditions. The limits of detectibility will be discussed in detail in Sect. 2.

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Broadband single-pulse CARS spectra in a fired internal combustion engine

Cited by 99 publications

References 7 publications

Laser diagnostics and minor species detection in combustion using resonant four-wave mixing

Laser diagnostics and minor species detection in combustion using resonant four-wave mixing

Rotational CARS: a comparison of different techniques with emphasis on accuracy in temperature determination

Experimental study of vibrational and pure rotational coherent anti-stokes Raman scattering (CARS) in molecular hydrogen

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