Now showing items 4-23 of 32

• #### Detection of direct and indirect noise generated by synthetic hot spots in a duct ﻿

(2016-06)
Indirect noise generated by the acceleration of entropy or vorticity perturbations through a nozzle is of interest both as an additional source of transmitted noise, but also as a source of combustion instabilities via ...
• #### Detection of direct and indirect noise generated by synthetic hot spots in a duct ﻿

(Elsevier, 2017-04-28)
Sound waves in a combustor are generated from fluctuations in the heat release rate (direct noise) or the acceleration of entropy, vorticity or compositional perturbations through nozzles or turbine guide vanes (indirect ...
• #### Direct and indirect noise generated by entropic and compositional inhomogeneities ﻿

Flow disturbances are generated inside a duct via pulsed injection of helium into a flow of air. This leads to the generation of an acoustic pulse (direct noise), as well as the production of entropic and compositional ...
• #### Direct and indirect noise generated by injected entropic and compositional inhomogeneities ﻿

(American Sociery of Mechanical Engineers, 2017-06)
Flow disturbances are generated inside a duct via pulsed injection of helium into a flow of air. This leads to the generation of an acoustic pulse (direct noise), as well as the production of entropic and compositional ...
• #### Extracting flame describing functions in the presence of self-excited thermoacoustic oscillations ﻿

One of the key elements in the prediction of thermoacoustic oscillations is the determination of the acoustic response of flames as an element in an acoustic network, in the form of a flame describing function (FDF). In ...
• #### Favre- and Reynolds-averaged velocity measurements: interpreting PIV and LDA measurements in combustion ﻿

(Elsevier, 2014-07-04)
Previous studies using particle image velocimetry (PIV) and laser Doppler anemometry (LDA) have raised the question of how these measurements should be compared. This study reports on the difference between Favre-averaged ...
• #### Flame structure, spectroscopy and emissions quantification of rapeseed biodiesel under model gas turbine conditions ﻿

(Elsevier Ltd, 2017-01-01)
The spray combustion characteristics of rapeseed biodiesel/methyl esters (RME) and 50% RME/diesel blend were investigated and compared with conventional diesel fuel, using a model swirl flame burner. The detailed database ...
• #### Flow Field Results of the Cambridge Stratified Swirl Burner Using Laser Doppler Anemometer ﻿

(Department of Engineering, University of Cambridge, 2012-06-08)
• #### High Spatial Resolution Laser Cavity Extinction and Laser Induced Incandescence in Low Soot Producing Flames ﻿

(Springer, 2015-06-26)
Accurate measurement techniques for in situ determination of soot are necessary to understand and monitor the process of soot particle production. One of these techniques is line-of-sight extinction, which is a fast, ...
• #### Igniter-induced hybrids in the 20-l sphere ﻿

(Elsevier, 2017-09-01)
Dust explosibility is traditionally described by two parameters, namely the maximum explosion pressure, P$_{max}$, and the deflagration index, K$_{St}$, usually determined through testing in a closed, pressure-resistant ...
• #### Large-Eddy Simulation of Pulverized Coal Jet Flame -Effect of Oxygen Concentration on NOx formation ﻿

(Elsevier, 2014-11-13)
Large-eddy simulation is applied to a laboratory-scale open-type pulverized coal flame generated by a triple stream burner, and the NO production and reduction in oxy- fuel condition are investigated for the first time. ...
• #### Laser diagnostics of pulverized coal combustion in O_2/N_2 and O_2/CO_2 conditions: velocity and scalar field measurements ﻿

(Springer, 2015-05-13)
Optical diagnostic techniques are applied to a 21 kW laboratory-scale pulverized coal–methane burner to map the reaction zone during combustion, in mixtures with varying fractions of O_2, N_2 and CO_2. Simultaneous Mie ...
• #### Measurements of the effect of boundary conditions on upstream and downstream noise arising from entropy spots ﻿

(The American Society of Mechanical Engineers, 2017-01-01)
Pressure fluctuations in combustors arise either directly from the heat release rate perturbations of the flame (direct noise), or indirectly from the acceleration of entropy, vorticity or compositional perturbations through ...
• #### Measuring ultrafine aerosols by direct photoionization and charge capture in continuous flow ﻿

(Taylor & Francis, 2018-05-04)
Direct ultraviolet (UV) photoionization enables electrical charging of aerosol nanoparticles with- out relying on the collision of particles and ions. In this work, a low-strength electric field is applied during particle ...
• #### Modelling of direct ultraviolet photoionization and charge recombination of aerosol nanoparticles in continuous flow ﻿

(AIP Publishing, 2017-01-14)
© 2017 Author(s).Ultrafine aerosol particles are electrically charged in a range of devices to enable their detection, capture, and control. Direct ultraviolet (UV) photoionization enables increased charging of some ...
• #### Nonlinear dynamics of a self-excited thermoacoustic system subjected to acoustic forcing ﻿

(Elsevier, 2014-06-25)
We experimentally study the nonlinear dynamics of a self-excited thermoacoustic system subjected to acoustic forcing. Our aim is to relate these dynamics to the behavior of universal model oscillators subjected to external ...
• #### Nonlinear dynamics of a self-excited thermoacoustic system subjected to acoustic forcing ﻿

(Elsevier, 2014-06-25)
We experimentally study the nonlinear dynamics of a self-excited thermoacoustic system subjected to acoustic forcing. Our aim is to relate these dynamics to the behavior of universal model oscillators subjected to external ...
• #### Planar 2-color time-resolved laser-induced incandescence measurements of soot in a diffusion flame ﻿

Planar two-dimensional two-colour time-resolved laser-induced incandescence (2D-2C-TiRe-LII) is employed to investigate soot formation in a standard ethylene laminar di usion ame. The time resolution of the 2D LII signal ...
• #### PLIF Measurements of Nitric Oxide and Hydroxyl Radicals Distributions in Swirled Stratified Premixed Flames ﻿

(Instituto Superior Técnico - Center for Innovation, Technology and Policy Research, Instituto Superior Técnico - Center for Innovation, Technology and Policy Research, 2016-07-04)
Environmental and economic concerns have pushed aeronautical authorities to set stringent environmental regulations on fuel consumption, noise production, and pollutant emission. Engine manufacturers are developing novel ...
• #### Quantitative Temperature Measurement of High Pressure CH$_{4}$/O$_{2}$/N$_{2}$ Laminar Flames Using Laser Induced Thermal Grating Spectroscopy (LITGS) ﻿

(Combustion Society of Japan, Combustion Society of Japan, 2016-10)
Laser diagnostics for quantitative measurements of temperature are important in high pressure and high temperature environments. In this study, Laser Induced Thermal Grating Spectroscopy (LITGS) is employed for oxygen ...