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Showing 1 to 16 of 16 for “"soot volume fraction"”.
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Laser Induced Incandescence for Volume Fraction and Relative Particle Size Measurements in a Rich-Quench-Lean Jet A Combustor
… particulate matter, which is composed mostly of soot, is an important goal for modern aeroengine combustors. Not only does soot production reduce engine performance, but it also creates unwanted pollution. In order to understand soot production in realistic environments, this thesis focuses on …
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Laser induced incandescence imaging for the investigation of soot formation in laminar flames
… incandescence imaging for the measurement of soot concentration within a variety of novel flame sources and setups. Laser induced incandescence (LII) is an optical technique used in laser diagnostics to measure soot volume fraction and estimate particle size in-situ. Using imaging to measure …
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Laser diagnostics of soot in hydrocarbon diffusion flames
Driven by the demand for soot-free combustion, laser-based diagnostic techniques on soot have been developing since the late 1980s. One of these techniques is line-of- sight extinction, which is a fast, low-cost, and quantitative method to investigate the soot volume fraction in flames. However, …
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Simulating high flux solar radiation and assessing its influence on a sooty flame
… influence of concentrated solar radiation on the soot volume fraction and temperature in a laminar sooty flame. Detailed laser diagnostics was performed on a laminar sooty flame with and without the irradiance of CSR, because laser diagnostics are demonstrated to hold the advantages of being …
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Experimental investigation on the effect of the combustion of oxygenated fuels on the formation of soot
… the potential pollutants (particularly soot) generated during the combustion of oxygenated fuel because of their distinct chemical composition when compared to fossil-based fuels. To have a through investigation on oxygenated fuel combustion and its impact on soot formation, three …
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Flow Field and Soot Formation Characteristics in Swirl-stabilized Non-premixed Turbulent Flames
Soot formation and evolution in relation with the flow fields were investigated experimentally in turbulent swirl-stabilized non-premixed flames using three different fuels: methane, ethanol and aviation Jet A-1. The studied flames were confined and stabilized in a model gas turbine combustor with …
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Sooting behaviour of turbulent non-premixed jet flames.
Soot measurements using planar laser-induced incandescence (LII) have been performed in three commercial propane-fired flames produced by simple jet (SJ), precessing jet (PJ-P) and bluff-body jet (BB) burners. The flames span a wide range of different global mixing rates for the same nozzle …
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On the Use of Laser-Induced Incandescence for Soot Diagnostics: From Theoretical Aspects to Applications in Engines
… diagnostic technique for measurements of soot volume fraction and particle size. The technique relies on detection of incandescent light from soot particles heated to around 4000 K using nanosecond laser pulses. A theoretical model for LII has been implemented and improved in order to …
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An Experimental Study of Soot Formation in Dual Mode Laminar Wolfhard-Parker Flames
An experimental study of sooting characteristics of laminar underventillated ethylene non-premixed flames in hot vitiated environments was performed using a modified Wolfhard-Parker co-flowing slot burner. The burner could be operated in "single mode" with a cold air/oxygen mixture as the oxidizer …
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Flamelet modelling of soot formation in diffusion flames
… unsteady flamelet models have been applied to soot formation in laminar and turbulent diffusion flames. The aim was to study how different model parameters affect soot formation in diffusion flames. It was shown that certain assumptions are more crucial in laminar diffusion flames than in …
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Evaluation and Mitigation of Industrial Fire Hazards
… detector activation. The temperature, velocity, soot, CO2, CO and oxygen concentration were determined in the plume above a fire. Close agreement was found between the different compound fields. A CFD simulation of the same plume closely matched the experiments. However, there are large …
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Numerical Modeling of Turbulent Combustion and Flame Spread
… model, flamelet combustion model, various soot models and transpired wall function. Comprehensive numerical simulations have been carried out to study soot formation and oxidation in turbulent buoyant diffusion flames, flame heat transfer and flame spread in fires. The gas temperature and …
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Numerical Modelling of Sooting Laminar Diffusion Flames at Elevated Pressures and Microgravity
Fully understanding soot formation in flames is critical to the development of practical combustion devices, which typically operate at high pressures, and fire suppression systems in space. Flames display significant changes under microgravity and high-pressure conditions as compared to …
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Development of novel laser diagnostic techniques for the quantitative study of premixed flames
… and precision could be performed in low pressure sooting flames without recourse to calibration. Both the high precision and accuracy of the technique allowed for the deduction that the temperature in the flames studied here is relatively insensitive to changes in pressure in stark contrast to the …
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Development Of A Two-Color Optical Diagnostic For The Determination Of Engine In-Cylinder Soot Temperature And Volume Fraction Evolution With A Flame-Calibrated Emissivity Model
… occurs in a high temperature region and soot production in a high equivalence ratio region within a specific temperature window. Combustion temperature, therefore, is a crucial variable that determines soot and NOx emissions under various combustion modes, and it is thus very important to …
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Experimental Investigation of Large Scale Aerodynamics on Soot Emissions in Swirling Flows
Soot are microscopic airborne particles that impact human health and global climate, and are released into the atmosphere as a result of incomplete combustion. Reducing soot formation from burners improves both their efficiency and emissions standards. Modern burners utilize the Rich-Quench-Lean …