Frontiers | Understanding and Interpreting Laser Diagnostics ...- advanced laser diagnostics for an improved understanding of premixed flame-wall interactions ,There is a wealth of existing experimental data of flames collected using laser diagnostics. The primary objective of this review is to provide context and guidance in interpreting these laser diagnostic data. This educational piece is intended to benefit those new to laser diagnostics or with specialization in other facets of combustion science, such as computational modeling. This review ... Numerical analysis of flame instabilities in ... - SAGE JournalsFundamental processes that promote complex flame behavior in narrow channels have been attributed to three mechanisms: 13 (i) thermal interactions between flame and wall; (ii) chemical interaction between species; and (iii) momentum interaction between flow field and a flame. While the first mechanism is specific to small geometries, the other ...
interaction, side-wall quenching, dimethyl ether In this study, relative heat release rate (HRR) distributions of stoichiometric premixed dimethyl ether (DME) flames are experimentally investigated during atmospheric side-wall quenching (SWQ), to provide both an improved understanding of phenomena in flame-wall interaction
Advanced laser diagnostics for an improved understanding of premixed flame-wall interactions A. Dreizler;B. Böhm. Proceedings of the Combustion Institute (2015)
Request PDF | Advanced Laser Diagnostics for an Improved Understanding of Premixed Flame-Wall Interactions | This review discusses the role of laser diagnostics in combustion science and ...
This funded PhD studentship provides an exciting opportunity to study flame-wall interactions using advanced laser diagnostics. The PhD will be working as part of a team that is providing fundamental, ground-breaking experimental measurements that resolve the thermo-fluid and thermo-chemical processes at gas/wall interfaces.
Advanced laser diagnostics for an improved understanding of premixed flame-wall interactions. ... Understanding the ignition mechanism of high-pressure spray flames.
Flame-wall interactions are scientifically interesting and are of great importance to any enclosed practical combustion process. Following a description of current understanding, the focus is on using optical diagnostics to probe thermal, fluidic, and chemical properties of head-on and sidewall quenching.
Transient, premixed turbulent flame-wall interaction in the head-on quenching regime is realized using a nozzle type burner (Fig. 1). A laser spark at the nozzle exit, r = 0 mm, z = 27 mm, ignites premixed air and fuel (refer to for more details). A flame then propagates orthogonally against a steel wall, where it eventually gets quenched due to the enthalpy losses.
For various operation conditions flow and scalar fields were extensively studied. For this purpose laser-diagnostics have been adapted and developed such as planar imaging at high repetition rates and combined flow and scalar field methods. These investigations significantly improved the understanding of underlying physical and chemical processes.
The results show that the cold wall can influence the premixed combustion process in the flame front, which is close to the wall but does not touch the wall, and results in the obviously declined concentrations of OH, H, and O radicals in the premixed combustion zone. After flame quenching, a high CO concentration can be observed near the wall ...
The main objectives are to (1) use advanced laser diagnostics to conduct simultaneous measurements of multiple flame related quantities to study flameholding, flashback, and axial fuel staging; (2) develop a comprehensive suite of computational models to simulate unsteady and transient processes related to flame stabilization and flashback; and ...
Diffusion-Flame / Wall Interactions in a Heavy-Duty DI Diesel Engine. 2001-01-1295. Over the past decade, laser diagnostics have improved our understanding of many aspects of diesel combustion. However, interactions between the combusting fuel jet and the piston-bowl wall are not well understood. In heavy-duty diesel engines, with typical fuels ...
Swirl-stabilized lean-premixed flame combustion dynamics: An experimental investigation of flame stabilization, flame dynamics and combustion instability control strategies April 2018 DOI: 10. ...
This paper reports on experimental investigations of turbulent flame-wall interaction (FWI) during transient head-on quenching (HOQ) of premixed flames. The entire process, including flame-wall approach and flame quenching, was analyzed using high repetition rate particle image velocimetry (PIV) and simultaneous flame front tracking based on laser-induced fluorescence (LIF) of the OH molecule ...
Meanwhile, multiple advanced laser diagnostics techniques are also adopted in different laboratory impinging flames to acquire more accurate and precise measurements of CO distributions in FWI. To gain more knowledge of pollutants emissions in FWI, the behaviors of soot from practical internal engines are observed with the aid of visualization ...
pollutants emissions. The profound understanding of the complicated combustion processes occurring in practical combustion devices was useful for researchers and engineers to design and optimize the devices with excellent combustion and emission performance. Flame-wall interactions (FWI) as one kind of fundamental combustion phenomenon
The work presented in the thesis concerns the developments of laser-based diagnostics and its application to the study of turbulent premixed combustion. The diagnostic developments, mainly concerned with planar laser-induced fluorescence (PLIF), are intended to provide instantaneous visualization of the key species originating from the combustion processes involved in the burning of ...
Dreizler , A. , Böhm B. Advanced laser diagnostics for an improved understanding of premixed flame-wall interactions Proceedings of the Combustion Institute 35 1 2014 37 64 10.1016/j.proci.2014.08.014
The work presented in the thesis concerns the developments of laser-based diagnostics and its application to the study of turbulent premixed combustion. The diagnostic developments, mainly concerned with planar laser-induced fluorescence (PLIF), are intended to provide instantaneous visualization of the key species originating from the ...
The Gastech 2022 Strategic Conference will gather leaders from industry, government, finance and technology to share insights and perspectives, as they discuss crucial industry topics, including changing gas demand dynamics, the impact of new technology, shifts in government policy, and the different solutions required to succeed in the face of growing global ambitions for sustainable ...
for the exceptional advancement of turbulent flames, laser diagnostics and combustion in reciprocating engines. Jonathan H. Frank, Sandia National Laboratories, United States for innovative development and application of laser diagnostic techniques for fundamental studies of flow-flame interactions in laminar and turbulent flames
Dreizler, A.: Wall heat fluxes and CO formation/oxidation during laminar and turbulent side-wall quench-ing of methane and DME flames. International J. of Heat and Fluid Flow (2019) 70:181
ABSTRACT Flame-acoustic interactions are witnessed in the context of combustion instability in gas turbine combustors and other propulsion devices, such as rockets, besides confined combustion systems in general, such as furnaces and heaters. The confinement causes acoustic standing wave modes that interact with the flame to cause fluctuations in all quantities to grow in amplitude. This ...
Experimental and kinetic modeling study of a low-pressure premixed flame ... Laser Diagnostic for ... of flame-wall interactions advanced with ...
This paper is focused on the characterization of local heat release rate and its correlation with flame structures under atmospheric conditions in a side-wall quenching geometry. The influence of different wall temperatures ranging from 330 K to 670 K is compared for stoichiometric and lean (ϕ = 1.0 and 0.83) methane/air as well as dimethyl ether (DME)/air flames. Simultaneous formaldehyde ...
