Lanthanide-based laser-induced phosphorescence for spray diagnostics

Journal Article · Tue Mar 15 00:00:00 EDT 2016 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.4943224· OSTI ID:22597083

Water, W. van de; Kunnen, R. P. J.; Clercx, H. J. H.; Maes, N. C. J.; Sweep, A. M.; Dam, N. J. ^[1]; Lamberts, T. ^[2]

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1. Mechanical Engineering Department, Eindhoven University of Technology, 5612 AZ Eindhoven (Netherlands)
2. Institute of Theoretical Chemistry, University of Stuttgart, D-70569 Stuttgart (Germany)

Laser-induced phosphorescence (LIP) is a relatively recent and versatile development for studying flow dynamics. This work investigates certain lanthanide-based molecular complexes for their use in LIP for high-speed sprays. Lanthanide complexes in solutions have been shown to possess long phosphorescence lifetimes (∼1-2 ms) and to emit light in the visible wavelength range. In particular, europium and terbium complexes are investigated using fluorescence/phosphorescence spectrometry, showing that europium-thenoyltrifluoracetone-trioctylphosphineoxide (Eu-TTA-TOPO) can be easily and efficiently excited using a standard frequency-tripled Nd:YAG laser. The emitted spectrum, with maximum intensity at a wavelength of 614 nm, is shown not to vary strongly with temperature (293-383 K). The decay constant of the phosphorescence, while independent of ambient pressure, decreases by approximately 12 μs/K between 323 and 373 K, with the base level of the decay constant dependent on the used solvent. The complex does not luminesce in the gas or solid state, meaning only the liquid phase is visualized, even in an evaporating spray. By using an internally excited spray containing the phosphorescent complex, the effect of vaporization is shown through the decrease in measured intensity over the length of the spray, together with droplet size measurements using interferometric particle imaging. This study shows that LIP, using the Eu-TTA-TOPO complex, can be used with different solvents, including diesel surrogates. Furthermore, it can be easily handled and used in sprays to investigate spray breakup and evaporation.

• OSTI ID: 22597083
• Journal Information: Review of Scientific Instruments, Vol. 87, Issue 3; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
DROPLETS
EUROPIUM
FLUORESCENCE
IMAGES
LIQUIDS
NEODYMIUM LASERS
PHOSPHORESCENCE
SOLIDS
SOLVENTS
SPECTRA
SPECTROSCOPY
SPRAYS
TERBIUM
TERBIUM COMPLEXES
TRIOCTYLPHOSPHINE OXIDE
TTA
WAVELENGTHS