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Showing 1 to 20 of 76 for “"Ignition Delay"”.
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Hot jet ignition delay characterization of methane and hydrogen at elevated temperatures
… study contributes to a better understanding of ignition by hot combustion gases which finds application in internal combustion chambers with pre-chamber ignition as well as in wave rotor engine applications. The experimental apparatus consists of two combustion chambers: a pre chamber that …
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Traversing hot jet ignition delay of hydrocarbon blends in a constant volume combustor
… as a rapid, distributed and moving source of ignition, traversing across one end of the long combustion chamber entrance, induces complex flow structures such as a train of counter rotating vortices that enhance turbulent mixing. In general, a stationary hot-jet ignition process lack these …
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Ignition delay study of next generation alternative jet fuels in a rapid compression machine
… primary goal of this study is to determine the ignition delay time of jet fuels of interest; conventional, alternative, and surrogate blends. By measuring the pressure trace of autoignition in rapid compression machine, ignition delay time is captured through the pressure derivative. Category A …
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Investigation of the Relationship of Ignition Delay Characteristics of a Hydrocarbon Fuel to Carbon Formation
Made available in DSpace on 2014-12-05T19:16:03Z (GMT). No. of bitstreams: 1 6402871.pdf: 1964960 bytes, checksum: 33ed561c2fd678f0e6e178e6eff60e7e (MD5) Previous issue date: 1963
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Ignition delay of oxygenated fuel droplets: development of a 1 second drop tower and initial 1-g test results
… combustion. In the present study, droplet ignition delay times of methyl butyrate and methanol are investigated. A bench experiment, conducted in normal gravity, was constructed and used to determine the ignition delay times of each fuel. Normal gravity experiments were conducted on both …
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Measurement of ignition delay time of jet fuels in shock tube for the development of the chemical kinetic mechanism
… measurement of both overall and first-stage ignition delays for F-24 at 5–20 bar down to ~650–700 K and providing comparative data for a cycloalkane-rich CycloSAF. A Covariance Matrix Adaptation Evolution Strategy (CMA-ES) is then employed to optimize selected Arrhenius parameters of the 16 …
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Shock Ignition of N-Heptane With Supplemental Hydrogen
… n-heptane (surrogate for diesel fuel) and air on ignition delay time at prototypic post-compression diesel engine conditions. Ignition delay time data was measured using the reflected shock wave technique at a pressure of 20 bar (representative of part load engine conditions), for three fuel …
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Autoignition and emission characteristics of gaseous fuel direct-injection compression-ignition combustion
… research. To improve understanding of the autoignition and emission characteristics of natural gas direct-injection compression-ignition combustion, the effects of key operating parameters (including injection pressure, injection duration, and pre-combustion temperature) and gaseous fuel …
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The effect of fuel injection pressure and in cylinder temperature on igniton delay, combustion performance and emission
The mixture formation prior to the ignition process plays as a key element in the diesel combustion. The objective of this research was to help an understand of the effects of air fuel mixing process during the ignition delay period and initial heat release in combustion process that strongly …
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Model-Based Control of Gasoline Partially Premixed Combustion
… of low temperature combustion concepts where the ignition delay is prolonged in order to promote the air-fuel-mixture homogeneity in the combustion chamber at the start of combustion. A more homogeneous combustion process in combination with high exhaust-gas recirculation (EGR) ratios gives lower …
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The role of fuel in determining the high load limit of controlled auto-ignition engines
Controlled Auto-Ignition (CAI) engines have the potential to increase fuel economy while lowering nitrogen oxide and soot emissions. One hurdle that is currently being faced is the engine's inability to operate at high loads due to a large Maximum Pressure Rise Rate (MPRR). To address this issue, …
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Ignition study in rapid compression machine
… it is necessary to compile information about the ignition delay, which governs auto-ignition in spark-ignition (SI), compression-ignition (CI) and homogeneous charge compression-ignition (HCCI) engines. In this study, we measured ignition delay on the Rapid Compression Machine (RCM). RCM is a …
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Rural electrification from local resources : biomass pyrolysis oil combustion in a direct injection diesel engine
… that these fuels exhibit excessively long ignition delay, rendering them dependant on auxiliary ignition sources for diesel engine operation. This work focuses on examining what physical and chemical processes may explain poor pyrolysis oil ignition quality, and what can be done to improve …
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The development of an enhanced autoignition sub-model for use in CFD combustion simulations
… efficient mathematical model of the fuel ignition characteristics that could be used in a CFD simulation of an internal combustion engine or any other generic combustion system. The validation of the model provided useful insight into the need for good quality experimental data for the …
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Study of lubrication oil ignition in a rapid compression machine under sporadic pre-ignition conditions
… toward down-sizing and turbo-charging spark ignition (SI) engines in an effort to increase fuel conversion efficiency. However, this has given rise to a destructive phenomenon known as sporadic pre-ignition (SPI). At low cranking speeds and high loads, engines have been observed to knock …
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Boron Particle Ignition and Combustion in a Shock Tube Using Time -Resolved Spectroscopy
… show a rapid decrease by a factor of four in ignition and burning times as the mole fraction ratio XF/XO2 is increased from 0 to 0.25. For values of XF/XO2 greater than 0.5 there is little change of ignition burning time with XF/XO2 . Spectroscopic data taken in pure oxygen environments show …
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Autoignition study of next generation aviation fuels and components
… hydrocarbon components by investigating their ignition delay times at various autoignition conditions. Complex multistage ignition behavior of fuels at specific conditions are further evaluated with rapid compression machine (RCM) experimental results and CHEMKIN chemical mechanism simulations. …
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Efficient development and uncertainty propagation of aviation fuel chemical kinetic models
… dynamics (CFD). The method uses experimental ignition delay data from a shock tube and a rapid compression machine as primary validation targets, which are then used for data-driven optimization of chemical kinetic mechanisms. To efficiently propagate and reduce model uncertainty, a hybrid …
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Autoignition and flame speed of premixed liquefied petroleum gas in a rapid compression machine: experimental results and reduced chemical kinetic mechanism
… and exhaust gas recirculation (EGR) on the autoignition and flame speeds of LPG/oxidizer/inert/EGR blends. Experiments were conducted with 100% propane and blends of propane with propene, ethane, isobutane, or n-butane. EGR was simulated with mixtures of Ar, CO2, CO, and NO at substitution …
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Performance and emission characteristics of a gas-diesel engine
… in a single-cylinder, two-stroke compression-ignition engine with a poppet-valve gas-diesel injector. The investigated injector geometries and engine operating parameters included: fuel injection angle, fuel jet interruption ratio, engine speed, load, beginning of injection timing, natural gas …
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