Spectral Investigations of Fluorescence Tracers in Automotive and Aviation Fuels under Cryogenic Conditions
This study investigated spectral laser-induced fluorescence signals of dyes in fuels for automotive and aerospace applications under low temperatures and cryogenic conditions down to 183 K. For this purpose, a fluorescence chamber was developed based on cooling with liquid nitrogen. The design enabl...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2024-01-01
|
| Series: | Sensors |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1424-8220/24/3/724 |
| _version_ | 1827354563625091072 |
|---|---|
| author | Matthias Koegl Jonas Vogler Lars Zigan |
| author_facet | Matthias Koegl Jonas Vogler Lars Zigan |
| author_sort | Matthias Koegl |
| collection | DOAJ |
| description | This study investigated spectral laser-induced fluorescence signals of dyes in fuels for automotive and aerospace applications under low temperatures and cryogenic conditions down to 183 K. For this purpose, a fluorescence chamber was developed based on cooling with liquid nitrogen. The design enabled a minimal inner chamber temperature of 153 K. Furthermore, the applicability of two-color LIF for liquid thermometry was evaluated under these conditions. The temperature determination was based on the temperature-sensitive fluorescence intensity ratio of the special dyes doped into the fuels determined in suitable spectral regions, which represented common bandpass filters. For this purpose, the fluorescence signals of the dye doped into the gasoline and jet fuel surrogate isooctane were tested as well as blends of isooctane and the ethanol biofuels E20 (comprising 80 vol.% isooctane and 20 vol.% ethanol), E40, and E100. Additionally, a realistic multi-component fuel Jet A-1 mixed with a suitable fluorescence dye was investigated. E100 was doped with Eosin-Y, and the remaining fuels were doped with Nile red. Temperature-dependent spectral LIF intensities were recorded in the range of 183 K–293 K, which simulate extreme environments for aerospace and automotive applications. Frozen fuel–dye mixtures cause significant extinction effects and prevent sufficient signal detection at low and cryogenic temperatures, defining the detection limit. A temperature decrease led to a spectral shift in the emission peaks of E100 doped with Eosin-Y toward shorter wavelengths, while the spectra of mixtures doped with Nile red were shifted toward longer wavelengths. The suggested bandpass filters produced the temperature-sensitive intensity ratio (the average over the temperature interval) of the dyes with the largest sensitivity for Jet A-1 (5.2%/K), followed by E100 (4.95%/K), E40 (4.07%/K), E20 (3.23%/K), and isooctane (3.07%/K), even at cryogenic temperatures. |
| first_indexed | 2024-03-08T03:49:29Z |
| format | Article |
| id | doaj.art-1de0528c72d0433994a97e2d2ee5e94b |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-03-08T03:49:29Z |
| publishDate | 2024-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-1de0528c72d0433994a97e2d2ee5e94b2024-02-09T15:21:39ZengMDPI AGSensors1424-82202024-01-0124372410.3390/s24030724Spectral Investigations of Fluorescence Tracers in Automotive and Aviation Fuels under Cryogenic ConditionsMatthias Koegl0Jonas Vogler1Lars Zigan2Institut für Thermodynamik, Professur für Energiewandlung, Fakultät für Luft-und Raumfahrttechnik, Universität der Bundeswehr München (UniBw M), D-85577 Neubiberg, GermanyInstitut für Thermodynamik, Professur für Energiewandlung, Fakultät für Luft-und Raumfahrttechnik, Universität der Bundeswehr München (UniBw M), D-85577 Neubiberg, GermanyInstitut für Thermodynamik, Professur für Energiewandlung, Fakultät für Luft-und Raumfahrttechnik, Universität der Bundeswehr München (UniBw M), D-85577 Neubiberg, GermanyThis study investigated spectral laser-induced fluorescence signals of dyes in fuels for automotive and aerospace applications under low temperatures and cryogenic conditions down to 183 K. For this purpose, a fluorescence chamber was developed based on cooling with liquid nitrogen. The design enabled a minimal inner chamber temperature of 153 K. Furthermore, the applicability of two-color LIF for liquid thermometry was evaluated under these conditions. The temperature determination was based on the temperature-sensitive fluorescence intensity ratio of the special dyes doped into the fuels determined in suitable spectral regions, which represented common bandpass filters. For this purpose, the fluorescence signals of the dye doped into the gasoline and jet fuel surrogate isooctane were tested as well as blends of isooctane and the ethanol biofuels E20 (comprising 80 vol.% isooctane and 20 vol.% ethanol), E40, and E100. Additionally, a realistic multi-component fuel Jet A-1 mixed with a suitable fluorescence dye was investigated. E100 was doped with Eosin-Y, and the remaining fuels were doped with Nile red. Temperature-dependent spectral LIF intensities were recorded in the range of 183 K–293 K, which simulate extreme environments for aerospace and automotive applications. Frozen fuel–dye mixtures cause significant extinction effects and prevent sufficient signal detection at low and cryogenic temperatures, defining the detection limit. A temperature decrease led to a spectral shift in the emission peaks of E100 doped with Eosin-Y toward shorter wavelengths, while the spectra of mixtures doped with Nile red were shifted toward longer wavelengths. The suggested bandpass filters produced the temperature-sensitive intensity ratio (the average over the temperature interval) of the dyes with the largest sensitivity for Jet A-1 (5.2%/K), followed by E100 (4.95%/K), E40 (4.07%/K), E20 (3.23%/K), and isooctane (3.07%/K), even at cryogenic temperatures.https://www.mdpi.com/1424-8220/24/3/724two-color LIF techniqueliquid temperatureNile redEosin-Ycryogenic conditionsfuels |
| spellingShingle | Matthias Koegl Jonas Vogler Lars Zigan Spectral Investigations of Fluorescence Tracers in Automotive and Aviation Fuels under Cryogenic Conditions Sensors two-color LIF technique liquid temperature Nile red Eosin-Y cryogenic conditions fuels |
| title | Spectral Investigations of Fluorescence Tracers in Automotive and Aviation Fuels under Cryogenic Conditions |
| title_full | Spectral Investigations of Fluorescence Tracers in Automotive and Aviation Fuels under Cryogenic Conditions |
| title_fullStr | Spectral Investigations of Fluorescence Tracers in Automotive and Aviation Fuels under Cryogenic Conditions |
| title_full_unstemmed | Spectral Investigations of Fluorescence Tracers in Automotive and Aviation Fuels under Cryogenic Conditions |
| title_short | Spectral Investigations of Fluorescence Tracers in Automotive and Aviation Fuels under Cryogenic Conditions |
| title_sort | spectral investigations of fluorescence tracers in automotive and aviation fuels under cryogenic conditions |
| topic | two-color LIF technique liquid temperature Nile red Eosin-Y cryogenic conditions fuels |
| url | https://www.mdpi.com/1424-8220/24/3/724 |
| work_keys_str_mv | AT matthiaskoegl spectralinvestigationsoffluorescencetracersinautomotiveandaviationfuelsundercryogenicconditions AT jonasvogler spectralinvestigationsoffluorescencetracersinautomotiveandaviationfuelsundercryogenicconditions AT larszigan spectralinvestigationsoffluorescencetracersinautomotiveandaviationfuelsundercryogenicconditions |