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In the present paper, a new biofuel ethylene glycol monomethyl ether soyate has been developed. The biofuel was synthesized with a refined soybean oil and ethylene glycol monomethyl ether as reactants and sodium as catalyst under 90°C. The synthesized crude product was purified and structurally identified through Fourier Transform Infrared Spectrum (FT-IR), 1H Nuclear Magnetic Resonance Spectroscopy (1H NMR) and Gel Permeation Chromatography (GPC) analyses. The physicochemical properties of the biofuel and its addition effects on properties of diesel fuel were measured according to China national standard test methods. A single cylinder diesel engine was employed to evaluate the influences of the biofuel on engine fuel economy and engine-out emissions of CO, HC, NOx and smoke.

A new oxygenate of di-(2-ethoxyethyl) carbonate was synthesized, and its structure was identified by FT-IR, 1H NMR and GC-MS analyses. The effects of addition of the substance to diesel fuel on fuel properties and engine performance were studied. Results showed that this oxygenate is miscible with individual hydrocarbons in any proportion under normal temperature of 25°C. When di-(2-ethoxyethyl) carbonate is introduced to a diesel fuel, kinematic viscosity does not change notably, smoke point increases linearly. Flash point and solidifying point decline remarkably even at low content level of 5%(v) of the oxygenate, whereas they do not decrease further notably with its content increasing. The compound does not exert corrosion effect on cupric metal. When a diesel engine was fueled with the diesel fuel containing 25%(v) of the oxygenate.

Premixed charge compression ignition (PCCI) combustion has been shown to be a promising combustion technique to improve the combustion process and simultaneously reduce both Nitrogen oxides (NOx) and particulate matter (PM) emissions. The combination of port dimethyl ether (DME) induction and in-cylinder diesel direct-injection compression ignition (DICI) combustion was studied in a YTR 2105 engine. The main purposes of this paper were to investigate the effects of DME introduction on the combustion and emission characteristics of a diesel engine. Results obtained revealed that PCCI combustion process was composed of the homogeneous charge compression ignition (HCCI) combustion and conventional diffusion combustion. As the DME quantity was increased, the start of combustion (SOC) was advanced. The peak values of in-cylinder pressure and mass averaged temperature increased as well as the maximum heat release rate of DME HCCI combustion.

Biodiesels, which are produced through the transesterification reaction of fatty acids with alcohols, are promising clean alternative fuels in substitution of conventional diesel fuels. In this paper, a novel biodiesel, triethylene glycol monomethyl ether cottonseed oil monoester (TGMECOM), was developed. It was synthesized through transesterification of refined cottonseed oil and triethylene glycol monomethyl ether (TGME) with KOH as catalyst. Its chemical structure was characterized through FTIR, 1H NMR and GC-MS analyses. To investigate the engine performance of TGMECOM, tests on a two-cylinder DI diesel engine were conducted with different concentrations blended into diesel fuel. The results indicate that, compared to diesel fuel, TGMECOM has higher cetane number and oxygen content. For TGMECOM, the combustion timing of engine is advanced, ignition delay is shortened, and the combustion is improved.

In this paper, plasma technology is used for diesel particulate treatment for a minibus manufactured by Hyundai Company. A Corona Discharged Particulate Plasma Collector (CDPPC) is developed and tested for removal of the diesel particulates. Firstly, experimental research of two CDPPCs are made on an engine dynamometer test bed. Performances of the CDPPCs are investigated including particulate reduction efficiency, pressure drop, and the influential factors are also checked. The tested engine is a D4BX Diesel engine equipped with the minibus. Secondly, the CDPPCs are tested with the minibus on a chassis dynamometer based on FTP 75 Driving Cycle. The results showed that the CDPPC could reduce the engine exhaust smoke to almost zero at low engine speed and the pressure drop of the CDPPC is comparative to the muffler. The most influential factors are the HVSS (High Voltage Supply System) Voltage and the engine speed.

An upgraded multizone model is developed in order to study the effects of fuel injection characteristics on DI diesel engine soot and NOx emissions. Effects of fuel spray characteristics, the movement and evaporation of droplet, and spray wall impingement are considered. NOx emission is predicted by the extended Zeldovich mechanism and soot emission is simulated by the current soot formation and oxidation model. The multizone model can be used to calculate cylinder pressure, heat release rate, engine performance, NOx and soot emissions, etc. In this paper, the boot injection and split injection are simulated. The simulation shows that the fuel injection characteristics have significant effects on the process of engine combustion and emissions. The NOx and PM emissions from DI diesel engine can be reduced simultaneously by optimizing the shape of injection rate, especially by boot injection.

A new type direct-injection stratified-charge combustion system for gasoline engines is developed by the authors. In the system, gasoline is directly injected into a cylinder near the end of compression stroke by a nozzle with the injection holes unequally spaced on its tip. The angles among sprays in the vicinity of spark plug are small, and become larger downstream along the direction of air swirl motion. Therefore the circularly concentration stratification form rich to lean of air-fuel mixture is mechanically realized to ensure the reliable ignition and smooth flame propagation in the inhomogeneous mixture after sparking. The selection of main parameters of the system, the performance and the combustion characteristics of the engine after optimization of those parameters are introduced in detail in this paper.

Proper fuel supply system is the crux to realize the stratified scavenging for small type of two-stroke gasoline engine. A simple and effective diaphragm fuel injection system (DFI) is developed in the paper, which mainly consists of diaphragm pump and injector, the DFI utilizes the crankcase pressure which reflects the inlet flow rate to meter and inject fuel. As low short-circuit at low load operation, stratified scavenging seems not necessary, so the conventional carburetor is preserved to function at low load. This makes the whole fuel system simple and effective. The paper describes the operation principle of the DFI, and results of test on a 30cm3 modified engine are also presented, including the performance of fuel supply and contrast of complex engine performance with the original carbureted engine.