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The Research and Motor octane numbers of Liquefied Petroleum Gas (LPG)
Author / Creator
Morganti, Kai
This paper presents an experimental study of the Research (RON) and Motor (MON) octane numbers of Liquefied Petroleum Gas (LPG). A comprehensive set of RON and MON data for mixtures of propane, propylene (propene), n-butane and iso-butane are presented, using a method that is consistent with the currently active ASTM Research and Motor test methods for liquid fuels. Empirical models which relate LPG composition to its RON and MON are then developed, such that the simplest relationships between the constituent speciesa mole fractions and the mixture octane rating are achieved. This is used to determine the degree of non-linearity between the composition and the RON and MON of different LPG mixtures. Finally, implications for LPG fuel quality standards are discussed briefly, as part of a suggested, more substantial undertaking by the community which also revisits the standard test procedures for measuring the RON and MON of LPG.
The impacts of compression ratio on the performance and emissions of ice powered by oxygenated fuels: A review
Author / Creator
Awad, Omar I.
Energy sources are becoming a governmental issue, with cost and stable supply as the main concern. Oxygenated fuels production is cheap, simple and eco-friendly, as a well as can be produced locally, cutting down on transportation fuel costs. Oxygenated fuels are used directly in an engine as a pure fuel, or they can be blended with fossil fuel. The most common fuels that are conceded under oxygenated fuels are ethanol, methanol, butanol Dimethyl Ether (DME), Ethyl tert-butyl ether (ETBE), Methyl tert-butyl ether (MTBE) and biodiesel that have attracted the attention of researchers. Due to the higher heat of vaporization, high octane rating, high flammability temperature, and single boiling point, the oxygenated fuels have a positive impact on the engine performance, combustion, and emissions by allowing the increase of the compression ratio. Oxygenated fuels also have a considerable oxygen content that causes clean combustion. The aim of this paper was to systematically review the impact of compression ratio (CR) on the performance, combustion and emissions of internal combustion engines (ICE) that are operated with oxygenated fuels that could potentially replace petroleum-based fuels or to improve the fuel properties. The higher octane rating of oxygenated fuels can endure higher compression ratios before an engine starts knocking, thus giving an engine the ability to deliver more power efficiently and economically. One of the more significant findings to emerge from this review study was the slight increases or decreases in power when oxygenated fuel was used at the original CR in ICE engines. Also, CO, HC, and NOx emissions decreased while the fuel consumption (FC) increased. However, at higher CR, the engine performance increased and fuel consumption decreased for both SI and CI engines. It was seen the NOx, CO and CO2 emissions of oxygenated fuels decreased with the increasing CR in the SI engine, but the HC increased. Meanwhile, in CI engine, the HC, CO and NOx decreased as the CR increased with biodiesel fuel. •Effect of compression ratio and oxygenated fuels on performance, combustion and emissions of SI and CI engines was investigated.•There is a significant reduction in engine emission by increasing compression ratio in SI engines.•Improvement in the BTE, SFC, and performance of SI and CI engines fueled with oxygenated by increasing the compression ratio.•Due the high oxygen content of oxygenated fuels the combustion efficiency improved by increasing the compression ratio.•Oxygenated fuels with a higher octane rating can endure higher CR before the engine starts knocking.