1,369 research outputs found
Comparative Investigation of the High Pressure Autoignition of the Butanol Isomers
Investigation of the autoignition delay of the butanol isomers has been
performed at elevated pressures of 15 bar and 30 bar and low to intermediate
temperatures of 680-860 K. The reactivity of the stoichiometric isomers of
butanol, in terms of inverse ignition delay, was ranked as n-butanol >
sec-butanol ~ iso-butanol > tert-butanol at a compressed pressure of 15 bar but
changed to n-butanol > tert-butanol > sec-butanol > iso-butanol at 30 bar. For
the temperature and pressure conditions in this study, no NTC or two-stage
ignition behavior were observed. However, for both of the compressed pressures
studied in this work, tert-butanol exhibited unique pre-ignition heat release
characteristics. As such, tert-butanol was further studied at two additional
equivalence ratios ( = 0.5 and 2.0) to help determine the cause of the
heat release.Comment: 4 pages, 4 figures, presented at the 2011 Meeting of the Eastern
States Sections of the Combustion Institut
UConnRCMPy: Python-based data analysis for rapid compression machines
The ignition delay of a fuel/air mixture is an important quantity in
designing combustion devices, and these data are also used to validate chemical
kinetic models for combustion. One of the typical experimental devices used to
measure the ignition delay is called a Rapid Compression Machine (RCM). This
paper presents UConnRCMPy, an open-source Python package to process
experimental data from the RCM at the University of Connecticut. Given an
experimental measurement, UConnRCMPy computes the thermodynamic conditions in
the reaction chamber of the RCM during an experiment along with the ignition
delay. UConnRCMPy implements an extensible framework, so that alternative
experimental data formats can be incorporated easily. In this way, UConnRCMPy
improves the consistency of RCM data processing and enables the community to
reproduce data analysis procedures.Comment: 8 pages, 3 figures, presented at the 10th US National Combustion
Meetin
An Autoignition Study of iso-Butanol: Experiments and Modeling
The autoignition delays of iso-butanol, oxygen, and nitrogen mixtures have
been measured in a heated rapid compression machine (RCM). At compressed
pressures of 15 and 30 bar, over the temperature range 800-950 K, and for
equivalence ratio of = 0.5 in air, no evidence of an NTC region of
overall ignition delay is found. By comparing the data from this study taken at
= 0.5 to previous data collected at = 1.0 (Weber et al. 2013), it
was found that the = 0.5 mixture was less reactive (as measured by the
inverse of the ignition delay) than the = 1.0 mixture for the same
compressed pressure. Furthermore, a recent chemical kinetic model of
iso-butanol combustion was updated using the automated software Reaction
Mechanism Generator (RMG) to include low- temperature chain branching pathways.
Comparison of the ignition delays with the updated model showed reasonable
agreement for most of the experimental conditions. Nevertheless, further work
is needed to fully understand the low temperature pathways that control
iso-butanol autoignition in the RCM.Comment: 6 pages, 4 figures, 8th US National Combustion Meetin
A Rapid Compression Study of the Butanol Isomers at Elevated Pressure
Investigation of the autoignition delay of the butanol isomers has been
performed at elevated pressure of 15 bar and low to intermediate temperatures
of 725-870 K. Stoichiometric mixtures made in nitrogen/oxygen air were studied.
For the temperature and pressure conditions in this study, no NTC or two-stage
ignition behavior were observed. The reactivity of the isomers of butanol, in
terms of inverse ignition delay, was ranked as n-butanol > sec-butanol ~
iso-butanol > tert-butanol. Predictions of the ignition delay by several
kinetic mechanisms available in the literature generally over-predict the
ignition delays.Comment: 6 pages, 4 figures, presented at the 7th US National Combustion
Meetin
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