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In 2017, the Chinese government issued a strategic policy of nationwide use of bioethanol as a gasoline-blending component by 2020 for the consideration of reducing smog and greenhouse gas (GHG) emissions. It is highly relevant to estimate the benefits of well-to-wheel (WTW) GHG emission savings using future engine technologies. However, literature about the WTW GHG emissions for ethanol blends did not cover the engine efficiency gains in engines with future technologies. In a previous publication from the authors’ group, an empirical model was developed to predict the anti-knock property and engine thermal efficiency gains of ethanol blends in spark-ignition (SI) engines. This paper is a follow-up study, looking at not only the potential engine thermal efficiency gains but also WTW GHG emissions in future engine technologies. More specifically, a case study of adding bioethanol to two representative E10 fuels (main- and premium-octane-grade fuels) from China was conducted. It is assumed that future engin...

It is known that species in the exhaust gas of automobile engines vary with fuel. As such, there is a need to understand the individual hydrocarbon (HC) and carbonyl (aldehydes and ketones) emissions from modern engines, especially as the use of alternative and renewable biofuels is set to rise. For gasoline, a promising candidate biofuel is 2,5-dimethylfuran (DMF). This work presents the key individual HCs that have been identified using gas chromatography mass spectrometry (GC/MS) and quantifies the emissions of 13 different carbonyls as specified by the California Air Resources Board (CARB) Method 1004 using high performance liquid chromatography (HPLC). The tests were conducted on a single cylinder direct-injection spark-ignition (DISI) engine at 1500 rpm, λ = 1 and constant ignition timing. For the GC analysis, the midrange HCs were identified using the mass spectra. The results showed that unburned fuel (DMF) dominates the emissions. Other main emissions include cyclopentadiene, methyl vinyl ketone,...

Combustion intermediates in low-pressure premixed laminar 2-methylfuran (MF)/oxygen/argon flames with equivalence ratios of 0.8 and 1.5 were investigated using tunable synchrotron vacuum ultraviolet photoionization and molecular beam mass spectrometry. MF is a promising biofuel with great potential of being used in different fields, including the auto industry. However, the combustion chemistry of MF is not clear. Photoionization mass spectra of MF/oxygen/argon flames were recorded as well as the photoionization efficiency curves (PIEs) of the combustion intermediates. Ionization energies (IEs) were measured from the PIEs. The combustion intermediates were identified by comparing the measured IEs to those reported in the literature or calculated with the method ab initio. Possible reaction pathways of MF and its primary combustion derivatives were constructed on the basis of the combustion intermediates identified. H abstraction and the consecutive reaction products were identified, including furfural, (Z...

The 2,5-dimethylfuran (DMF) has attracted renewed global interest since its improved production methods were published in Nature and Science in 2007. Its high energy density makes it a promising biofuel and a possible alternative to gasoline. Consequently, a series of studies, led by the University of Birmingham, aims to assess the potential of DMF as an automotive energy carrier. These studies will include an analysis of the spray properties, the laminar flame characteristics, the engine performance, and the subsequent emissions. This paper examines the laminar flame characteristics from a quiescent homogeneous air−fuel mixture. The experiments were conducted using a constant volume vessel and were recorded by high speed schlieren visualization. By measurement of the flame growth following ignition, the laminar flame speed was determined. The calculation of flame stretch yielded the Markstein lengths and the laminar burning velocities. This paper presents the results of DMF combustion for a range of equi...

Biomass has the potential to become an important source of energy for future automotive fuels. Recent biological and chemical improvements to the conversion of biomass-derived carbohydrates have produced high yields of liquid 2,5-dimethylfuran (DMF). This discovery has made DMF a possible substitute for petroleum-based gasoline, because they share very similar physicochemical properties, which are superior to those of ethanol. In the present study, experiments have been carried out on a single-cylinder gasoline direct-injection (GDI) research engine to study the performance of DMF benchmarked against gasoline and what is considered to be the current biofuel leader, ethanol. Initial results are very promising for DMF as a new biofuel; not only is the combustion performance similar to commercial gasoline, but the regulated emissions are also comparable.