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The injector driving strategy influences both the performance and the emission produced by internal combustion engines. The injector driving strategy is the intellectual property of the automotive industry; its disclosure is restricted to the automaker and the injection system supplier. The objective of this paper is to present a drive circuit for common rail diesel injectors. The circuit design is based on transient simulations using an equivalent virtual circuit, to be used on a test bench for injection strategies. The simulated electric current curve has been compared with experimental measurement under the same conditions in the projected circuit, the errors has remained at approximately 6%.

This study presents the effects of fuel blends containing 5%, 10%, 15% and 20% of anhydrous ethanol in diesel oil with 20% of biodiesel (B20) on performance, emissions and combustion characteristics of a diesel engine. The engine was tested with its original configuration and in the lower brake specific consumption region, at 1800 RPM. The results showed that in-cylinder peak pressure and heat release rate increased with the use of ethanol. The use of ethanol increased ignition delay and decreased exhaust gas temperature. Brake specific fuel consumption increased with ethanol addition, and fuel conversion efficiency was not affected. Increasing ethanol content in the fuel caused decreased carbon dioxide (CO2), carbon monoxide (CO) and total hydrocarbons (THC) emissions.

The solubility of ethanol in diesel oil with biodiesel is a limiting factor for its use as fuel for compression ignition engines. The stability of blends of ethanol with concentration varying from 5% to 30% in diesel oil containing 7% of biodiesel (B7) was evaluated at temperatures from 16°C to 25°C. The blends were conditioned in graduated glass cylinders and kept at the test temperatures, being observed the blend phase separation percentage in specific time schedules. The results show the stability time of each blend, indicating the maximum storage and use periods for the ethanol concentration evaluated. The results demonstrate that fuel blends with ethanol concentrations up to 15% can safely be used as engine fuels, as far as the tested parameters are concerned.

This paper presents an investigation on fuel consumption of a diesel engine fuelled with blends of natural gas-diesel and hydrogen-diesel. Experiments have been carried out in a 50 kW, four-stroke, diesel engine. Natural gas and hydrogen have both been injected in the intake manifold, while diesel was directly injected in the combustion chamber. Blends of 25%, 50% and 75% of natural gas in diesel were tested, while the concentrations of hydrogen were 20%, 30% and 50%. No alteration in the diesel injection system has been made when the gaseous fuels were used. The results show that diesel consumption is reduced proportionally to the necessary air amount for stoichiometric burn of the gaseous fuels.