A5028357443- Combustion and flame dynamics
- Advanced Combustion Engine Technologies
- Heat transfer and supercritical fluids
- Spectroscopy and Laser Applications
- Spectroscopy Techniques in Biomedical and Chemical Research
- Phase Equilibria and Thermodynamics
- Spectroscopy and Chemometric Analyses
- Fluid Dynamics and Heat Transfer
- Fluid Dynamics and Turbulent Flows
- Bee Products Chemical Analysis
- Atmospheric chemistry and aerosols
- Coal Combustion and Slurry Processing
- Thermochemical Biomass Conversion Processes
- Particle Dynamics in Fluid Flows
- Catalytic Processes in Materials Science
- Atmospheric and Environmental Gas Dynamics
Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)
2024
Lund University
2020-2022
Seoul National University
2015-2020
This paper presents a joint experimental and numerical study on premixed laminar ammonia/methane/air flames, aiming to characterize the flame structures NO formation determine speed under different pressure, equivalence ratio, ammonia fraction in fuel. The experiments were carried out lab-scale pressurized vessel with Bunsen burner installed concentric co-flow of air. Measurements NH distributions flames made using planar laser-induced fluorescence. A novel method was presented for...
While Raman spectroscopy provides opportunities for simultaneous detection and quantitative analysis of multiple species, it also suffers from certain limitations, such as low signal strength, which often makes unsuitable the study minor species. The present work employs a high-repetition-rate high-power laser re-introduces an amplification technique to improve limit, providing up 45-time enhancement. is achieved by employing multi-pass cavity, different modes were tested optimized...
Raman spectroscopy is a powerful technique that allows for simultaneous measurements of multiple species; however, it suffers from low signal intensity and, in diagnostics ammonia (NH3) combustion, strong flame fluorescence. The current work re-introduces multipass setup to perform enhanced quantitative major species and nitric oxide (NO) premixed laminar lean (φ = 0.9) NH3 flame. A way deal with the reaction-zone fluorescence proposed validated. were performed using both second (532 nm, NO...
A time-resolving filtering technique developed to improve background suppression in Raman spectroscopy is presented and characterized. The enables separation of signal contributions via their polarization dependency by the addition a waveplate normal measurement system data post-processing. As result, interferences broadband laser-induced fluorescence incandescence, as well flame luminosity blackbody radiation, were effectively suppressed from spectra. Experimental setting parameters method...
Abstract In this work, the effects of replacing an atomizer component a confined jet-stabilized gas turbine combustor with 3D-printed part have been studied. The is called airblast, and it serves as wall that collects flows liquid droplets for secondary atomization. Therefore, liquid-surface interaction on rough surface was interest. operated under various conditions either conventionally machined airblast or airblast. Flames two fuels were studied fuel flexibility, position primary...
Laser-based Raman spectroscopy is a powerful technique for non-intrusive measurements of chemical composition in gas, liquid, and solids. However, weak signals make it challenging to employ the diagnostics under harsh conditions with various background interferences. To overcome such limitations, we have devised method, polarization lock-in filtering (PLF) based on temporal modulation excitation laser polarization, filter out polarization-independent from acquired data. The PLF method...
Stray light is a known strong interference in spectroscopic measurements. Photons from high-intensity signals that are scattered inside the spectrometer, or photons enter detector through unintended ways, will be added to spectrum as an signal. A general experimental solution this problem presented here by introducing customized fiber for signal collection. The fiber-mount spectrometer consists of periodically arranged array that, combined with lock-in analysis data, capable suppressing...
Abstract Fuel and load flexibility have been increasingly important features of industrial gas turbines in order to meet the demand for increased utilization renewable fuels provide a way balance grid fluctuations due unsteady supply wind solar power. Experimental investigations were performed using standard third-generation dry low emission (DLE) burner under atmospheric pressure conditions study effect central pilot fuel addition, variations, hydrogen (H2) enrichment natural (NG) flame....
In order to enable flow visualization, a Raman scattering technique was applied liquid nitrogen jet within high-pressure chamber. The pressure conditions ranged from 2.0 MPa 5.0 MPa, thereby encompassing the critical of at 3.4 MPa. From cryogenic under subcritical and supercritical conditions, signal emitted with an intensity proportional density molecules. After normalization process, converted into relative values used for spray characteristic analysis. distributions in axial radial...
Abstract In this work, the effects of replacing an atomizer component a confined jet-stabilized gas turbine combustor with three-dimensional (3D)-printed part have been studied. The is called airblast, and it serves as wall that collects flows liquid droplets for secondary atomization. Therefore, liquid–surface interaction on rough surface 3D-printed was interest. operated under various conditions either conventionally machined airblast or airblast. Flames two fuels were studied fuel...
Abstract Fuel and load flexibility have been increasingly important features of industrial gas turbines in order to meet the demand for increased utilization renewable fuels provide a way balance grid fluctuations due unsteady supply wind solar power. Experimental investigations were performed using standard 3rd generation dry low emission (DLE) burner under atmospheric pressure conditions study effect central pilot fuel addition, variations hydrogen (H2) enrichment natural (NG) flame....