Characterization of tracers for two-color laser-induced fluorescence liquid-phase temperature imaging in sprays

Prenting, Markus Michael; Dzulfida, Muhammad Imran Bin; Dreier, Thomas; Schulz, Christof

doi:10.1007/s00348-020-2909-9

Cited by 26 publications

(14 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Münsterjohann et al performed 2D temperature maps of FSP by employing a two-line atomic fluorescence method based on the presence of an indium tracer that was fed as a precursor during particle synthesis. More recently, Prenting et al screened different dye tracer molecules for two-color LIF and applied efficient coumarin 152 to demonstrate 2D temperature mapping of liquid ethanol droplets during spray combustion. Besides diagnostics in flames, LIF has also been used to investigate the chemistry of alkaline Na vapor in reaction with TiCl 4 and BCl 3 for TiB 2 nanoparticle synthesis in a counter-flow diffusion reactor …”

Section: Experimental Process and Nanoparticle Diagnosticsmentioning

confidence: 99%

Synthesis of Metal Oxide Nanoparticles in Flame Sprays: Review on Process Technology, Modeling, and Diagnostics

Meierhofer

Fritsching

2021

Energy Fuels

View full text Add to dashboard Cite

The gas synthesis of nanoparticles has gained major interest by different industries and research groups for the development of new materials and their subsequent implementation in numerous devices and applications. Actually, there are numerous research and application activities in flame-based nanoparticle production, mainly focusing on the process and its development, the in situ and ex situ analyses in experiments and simulations and new material and material combination developments. This review provides an overview on the flame synthesis of metal oxide nanoparticles and focuses in particular on the process design of flame spray pyrolysis (FSP). The first part of this review describes the historical background of flame-based particle production and further summarizes the emerging developments, achievements, and trends during the past 2 decades. The second part covers a general process overview of the flame aerosol-based manufacturing by explaining the key aspects of synthesis (chemical raw materials, metal precursors, solvents, and reactor configurations), in situ conditioning approaches, and powder and byproduct collection, along with additional post-processing steps (storage, handling, and modification). Applications of flame-made nanoparticles involve catalysts, gas sensors, energy storage materials, and nanotoxicity studies, among others, which will not be discussed in detail but are overviewed by listing the latest reviews of the respective field. The third part focuses on the growth mechanisms of solid particle products in liquid droplet/spray pyrolysis (liquid-to-particle and gas-to-particle conversion). The concept of characteristic process times is then exemplified for a lab-scaled FSP reactor, while afterward, particle dynamics and continuum models for reactor simulation are reviewed. The fourth part is a survey of more than 20 different diagnostic techniques that are commonly employed for characterization of reactive sprays and flame-made powders. We briefly explain the metrology basics of each method, indicate advantages and limitations, and present exemplary measurement results that have been acquired on flame reactor facilities for particle synthesis. Finally, we summarize the review and address some current challenges that might potentially shape the near future of nanoparticle synthesis in flame sprays.

show abstract

Section: Experimental Process and Nanoparticle Diagnosticsmentioning

confidence: 99%

Synthesis of Metal Oxide Nanoparticles in Flame Sprays: Review on Process Technology, Modeling, and Diagnostics

Meierhofer

Fritsching

2021

Energy Fuels

View full text Add to dashboard Cite

show abstract

“…To define reasonable standard operation conditions and to understand the individual process steps in detail, a comprehensive database of boundary conditions and reproducible experiments is required. The investigations to fill the database are still in the early stages and require extensive studies to enable a characterization of the burner performance and to gain a deep understanding of the process (Abdelsamie and Thévenin, 2019;Aßmann et al, 2020;Bieber et al, 2019;Keller et al, 2020;Martins et al, 2020;Prenting et al, 2020;Stodt et al, 2019a,b), Stodt et al (2020). A detailed characterization of the primary and secondary atomization of the SpraySyn burner is necessary to assess the performance of this atomizer reference device from the very beginning of the process chain.…”

Section: Introductionmentioning

confidence: 99%

Drop Dynamics in Heterogeneous Spray Flames for Nanoparticle Synthesis

2020

View full text Add to dashboard Cite

In flame spray pyrolysis (FSP), the understanding of the atomization and spray formation of the coaxial atomizer is a key step to control the mixing of reactants, and precursor release, as well as nanoparticle formation and growth mechanisms. The drop size and drop dynamics of fuel/precursor mixtures are relevant parameters to control the particle synthesis via gas-to-particle conversion for tailoring the nanoparticle. The investigation of the multiphase flow structures, especially in the dense spray region using sophisticated nonintrusive laser diagnostics, such as phase Doppler anemometry (PDA), enables a characterization of the burner with multiscale spatial and temporal resolution. In the present work, the evolution of drop size and velocity under varying iron nitrate (FNT) concentration of the precursor is investigated allowing for an estimation of precursor release and evaporation via detailed PDA measurements. The drop size distributions of pure ethanol, and ethanol + 2-ethylhexanoic acid, as well as for FNT-based spray flames, were studied in order to reveal the influence of metal precursors on the combustion. Drop size/velocity correlations were determined in order to resolve the size class averaged evolution of drop velocities. The evolution of the drop size distribution along the axial centerline revealed a variation of the evaporation rate in space and increased evaporation rates for FNT containing spray flames. Furthermore, bimodal drop size distributions were observed for heights above the burner larger than 40 mm in FNT precursor spray flames, indicating the occurrence of possible µ-explosions of drops, that have been reported in the literature for similar systems but only in single-droplet experiments so far.

show abstract

“…Regarding the gain medium, we have observed a shift of PL emission of the studied microsphere below the lasing threshold. In particular, a shift of 2 nm was observed for temperature increase from 36 • C to 44 • C which is equivalent to 0.25 nm/ • C. The blue shift of PL emission of RhB with increasing temperature is well-known and has been reported [29]. This shift is amplified when the sphere works under the lasing regime (above lasing threshold).…”

Section: Resultsmentioning

confidence: 69%

Biological miniature temperature sensor based on monodisperse microsphere lasers fabricated by soft microfluidic technology

Nguyen¹,

Nguyen²,

Hong³

et al. 2022

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

Microsphere biolasers employing biological materials as their cavity matrix have attracted tremendous research attention due to their potential for bio-integration, cell-tracking and biosensing. Several techniques have been applied for fabricating microsphere biolasers such as emulsion and vacuum freeze-drying but the current technology generally can not control the output size of the laser and therefore hinder them from many applications. In this work, we demonstrate that a low-cost microfluidic device can be very effective in fabricating nearly monodisperse dye-doped protein microspheres with up to 70% of them having the same size. Under optical pumping, these microspheres emit lasing emission with a lasing threshold of ~1 µJ and a quality (Q) factor of ~2.5×103. The lasing mechanism is ascribed to whispering gallery mode. Furthermore, the obtained microlasers can be employed for temperature sensing based on the wavelength shift of lasing mode with increasing temperature. The sensor sensitivity in the measured range of 25÷50 °C is about 0.47 nm/°C. More interestingly, microlasers of the same size exhibit a very similar sensing performance which confirm their high reproducibility and reliability. Owing to the biocompatibility and small size, these miniature laser-based sensors can be implantable in skins and tissues for biological studies and medical diagnostic.

show abstract

Characterization of tracers for two-color laser-induced fluorescence liquid-phase temperature imaging in sprays

Cited by 26 publications

References 29 publications

Synthesis of Metal Oxide Nanoparticles in Flame Sprays: Review on Process Technology, Modeling, and Diagnostics

Synthesis of Metal Oxide Nanoparticles in Flame Sprays: Review on Process Technology, Modeling, and Diagnostics

Drop Dynamics in Heterogeneous Spray Flames for Nanoparticle Synthesis

Biological miniature temperature sensor based on monodisperse microsphere lasers fabricated by soft microfluidic technology

Contact Info

Product

Resources

About