Temperature imaging in low-pressure flames using diode laser two-line atomic fluorescence employing a novel indium seeding technique

Borggren, Jesper; Burns, Iain S.; Sahlberg, Anna Lena; Aldén, Marcus; Li, Zhongshan

doi:10.1007/s00340-016-6329-8

Cited by 18 publications

(10 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An established technique that has, in recent times, received increased attention from the combustion research field, as it has the possibility to provide measurements with 278 Page 2 of 10 flames [6,[17][18][19], although, at the expense of time-averaged measurements due to the lower laser power. The advantage of using diode lasers is that they offer better control of the excitation wavelength and more stable power output resulting in better accuracy as well as enabling simultaneous path-integrated concentration measurements.…”

Section: Introductionmentioning

confidence: 99%

Diode laser-based thermometry using two-line atomic fluorescence of indium and gallium

et al. 2017

Self Cite

View full text Add to dashboard Cite

the requirements listed above, is two-line atomic fluorescence (TLAF) [4][5][6]. TLAF is a laser-based ratiometric technique, in which the temperature-dependent population of two lower lying electronic states, of a seeded atom, is probed by laser excitation and the ratio of the resulting fluorescence is correlated with the temperature of the gas. TLAF offers several beneficial features for temperature measurements in reactive flows. Firstly, no a priori knowledge of the combustion environment is necessary as the technique is independent of quenching due to the excitation to a common upper state [7]. Secondly, the use of an atomic species as temperature marker offers advantages such as providing high transition probabilities yielding strong fluorescence signals as well as being free from errors related to vibrational and rotational energy transfer existing in molecules [8,9]. Thirdly, TLAF also has the possibility for thermometry measurements in sooting and particulate-laden flames as the detection wavelength can be shifted from the excitation wavelength [10,11]. The disadvantage of TLAF is that an atomic species, not normally present in the flame, has to be introduced which may add complexities to the experimental set-up.Two-line atomic fluorescence has been developed in steps where the first theoretical ground work was conducted by Alkemade [7] and experimentally demonstrated shortly thereafter using atomic lamps [12,13]. With the advent of suitable lasers, TLAF became a tool for temperature measurements with imaging capabilities in non-steady environments [4,10,11,[14][15][16]. Recently, TLAF measurement has been extended from the linear regime to non-linear regime by Medwell et al. [4] and to the saturation regime by Manteghi et al. [14] in an attempt to maximize the fluorescence signal for instantaneous temperature measurements. With the improvement in regards to available power and wavelengths of diode lasers, TLAF measurements using diode lasers have been shown to give accurate temperatures in both low-pressure and atmospheric Abstract A robust and relatively compact calibration-free thermometric technique using diode lasers two-line atomic fluorescence (TLAF) for reactive flows at atmospheric pressures is investigated. TLAF temperature measurements were conducted using indium and, for the first time, gallium atoms as temperature markers. The temperature was measured in a multi-jet burner running methane/air flames providing variable temperatures ranging from 1600 to 2000 K. Indium and gallium were found to provide a similar accuracy of ~ 2.7% and precision of ~ 1% over the measured temperature range. The reliability of the TLAF thermometry was further tested by performing simultaneous rotational CARS measurements in the same experiments.

show abstract

Section: Introductionmentioning

confidence: 99%

Diode laser-based thermometry using two-line atomic fluorescence of indium and gallium

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…In the TLAF two different lower levels of the indium atom are excited to a common upper level. The ratio of the fluorescence signals induced by the two excitations is used to derive the temperature26 . In the present work, a similar measurement system was adopted as the one developed by Borggren et al with atomic indium26 .…”

mentioning

confidence: 99%

A novel multi-jet burner for hot flue gases of wide range of temperatures and compositions for optical diagnostics of solid fuels gasification/combustion

Weng

Borggren

et al. 2017

Review of Scientific Instruments

Self Cite

View full text Add to dashboard Cite

A novel multi-jet burner was built to provide one-dimensional laminar flat flames with a wide range of variable parameters for multipurpose quantitative optical measurements. The burner is characterized by two independent plenum chambers, one supporting a matrix of 181 laminar jet flames and the other supporting a co-flow from a perforated plate with small holes evenly distributed among the jets. A uniform rectangular burned gas region of 70 mm × 40 mm can be generated, with a wide range of temperatures and equivalence ratios by controlling independently the gas supplies to the two plenum chambers. The temperature of the hot gas can be adjusted from 1000 K to 2000 K with different flame conditions. The burner is designed to seed additives in gas or liquid phase to study homogeneous reactions. The large uniform region can be used to burn solid fuels and study heterogeneous reactions. The temperature was measured using two-line atomic fluorescence thermometry and the temperature profile at a given height above the burner was found to be flat. Different types of optical diagnostic techniques, such as line of sight absorption or laser-induced fluorescence, can be easily applied in the burner, and as examples, two typical measurements concerning biomass combustion are demonstrated.

show abstract

“…Therefore, IRPS signals at high temperatures were recorded at atmospheric pressure. Assuming the same gas composition, the collision broadening of a spectral line with pressure and temperature can be approximated as 32,33 where Δν coll ( p 0 , T 0 ) is the collision broadening at the reference temperature T 0 and pressure p 0 . Based on this, it was assumed that the pressure and temperature effects on the spectral linewidth of the IRPS signal could be considered separately.…”

Section: Theorymentioning

confidence: 99%

“…The temperature in the same flames has been measured by Borggren et al. 33 using the two-line atomic fluorescence (TLAF) technique. Recording the line ratio in these flames gives a calibration for the H 2 O line ratio at different temperatures.…”

Section: Measurementsmentioning

confidence: 99%

Mid-Infrared Polarization Spectroscopy Measurements of Species Concentrations and Temperature in a Low-Pressure Flame

et al. 2019

Self Cite

View full text Add to dashboard Cite

We demonstrate quantitative measurements of methane (CH 4 ) mole fractions in a low-pressure fuel-rich premixed dimethyl ether/oxygen/argon flat flame (Φ = 1.87, 37 mbar) using mid-infrared (IR) polarization spectroscopy (IRPS). Non-intrusive in situ detection of CH 4 , acetylene (C 2 H 2 ), and ethane (C 2 H 6 ) in the flame was realized by probing the fundamental asymmetric C–H stretching vibration bands in the respective molecules in the spectral range 2970–3340 cm −1 . The flame was stabilized on a McKenna-type porous plug burner hosted in a low-pressure chamber. The temperature at different heights above the burner (HAB) was measured from the line ratio of temperature-sensitive H 2 O spectral lines recorded using IRPS. Quantitative measurements of CH 4 mole fractions at different HAB in the flame were realized by a calibration measurement in a low-pressure gas flow of N 2 with a small admixture of known amount of CH 4 . A comprehensive study of the collision effects on the IRPS signal was performed in order to quantify the flame measurement. The concentration and temperature measurements were found to agree reasonably well with simulations using Chemkin. These measurements prove the potential of IRPS as a sensitive, non-intrusive, in situ technique in low pressure flames.

show abstract

Temperature imaging in low-pressure flames using diode laser two-line atomic fluorescence employing a novel indium seeding technique

Cited by 18 publications

References 25 publications

Diode laser-based thermometry using two-line atomic fluorescence of indium and gallium

Diode laser-based thermometry using two-line atomic fluorescence of indium and gallium

A novel multi-jet burner for hot flue gases of wide range of temperatures and compositions for optical diagnostics of solid fuels gasification/combustion

Mid-Infrared Polarization Spectroscopy Measurements of Species Concentrations and Temperature in a Low-Pressure Flame

Contact Info

Product

Resources

About