Alternative Fuels for Internal Combustion Engines

Researchers have studied on alternative fuels that can be used with gasoline and diesel fuels. Alternative fuels such as hydrogen, acetylene, natural gas, ethanol and biofuels also uses in internal combustion engines. Hydrogen in the gas phase is about 14 times lighter than the air. Moreover, it is the cleanest fuel in the world. On the other hand because of its high ignition limit (4–75%), low ignition energy, needs special design to use as pure hydrogen in internal combustion engines. It is proved that hydrogen improves the combustion, emissions and performance, when is added as 20% to fuels. Natural gas is generally consisting of methane (85–96%) and it can be used in both petrol and diesel engines. Ethanol can be used as pure fuel or mixed with different fuels in internal combustion engines. In this section, the effects of natural gas, hydrogen, natural gas + hydrogen (HCNG), ethanol, ethanol + gasoline, ethanol + hydrogen, acetylene, acetylene + gasoline mixtures on engine performance and emissions have been examined

Investigation of performance and emission characteristics fueled by diesel, diesel- TiO2 and diesel ash in a diesel engine

It is available in the literature that adding nanomaterials as additives to diesel fuel can improve engine performance and emission values. Many researchers have been worked in this field. In this study, the effects of adding nano-Ash and nano-TiO2 to diesel fuel have been investigated. In the test, brake thermal effciency and brake specific fuel consumption values and CO, CO2, HC, NOx values for emissions have been measured. Performance metrics have analyzed under five engine load conditions with a constant speed of 1500 rpm. These nanoparticles have added to the diesel as 1 gram per liter. Nanoparticles and diesel have been mixed for 1 hour with an ultrasonic mixer. These three different fuels (pure diesel, TiO2 (1 gr) +Diesel (1 liter) and Ash (1 gr) +Diesel (1 liter)) have compared at constant speed (1500 rpm) and different loads. The results of this study showed that diesel TiO2 and Ash addition increased BTE by 1% to 8% compared to diesel. With the addition of TiO2 to diesel, HC, CO and CO2 values decreased. The ash addition HC and CO2 decreased, while CO increased. The reason for the increase in CO is that 87% of the chemical content of ash is carbon. The addition of TiO2 to diesel, NO decreased. With the addition of ash, NO decreased. Ash addition was higher in all HC and NO emission values.</p

EXPERIMENTAL INVESTIGATION OF PERFORMANCE AND EMISSIONS OF AN SI ENGINE FUELED BY ACETYLENE-METHANE AND ACETYLENE-HYDROGEN BLENDS

The aim of this paper is analysing of performance parameters and emission values of an SI engine fuelled by acetylene-hydrogen and acetylene-methane blends. The experiments were carried out at a fixed bmep (brake mean effective pressure) of 2.095 bar, a load of 30 Nm and an engine speed of 1500 rpm under lean mixture conditions (lambda=1.3-2.8). Moreover, the flow rates of the blends were changed as volumetrically. The parameters of brake thermal efficiency, specific fuel consumption, cylinder pressure, heat release rate and emissions were analysed for each fuel blends. The experimental results showed that the values of specific fuel consumption are declined between 18.5% and 20.1% by hydrogen addition and raised about 64% with methane addition in the blend. The values of brake thermal efficiency are declined between 6.2% and 3.3% with the addition of hydrogen and are decreased about 10% by the addition of methane in the blend. The curves of cylinder pressure and heat release rate are advanced to top dead centre by the adding of hydrogen to acetylene. But the curves are retarded with methane addition. The adding of hydrogen in acetylene leads to a decrease in CO and HC emissions and an increase in NOx values for fixed lambda. But the increasing of methane fraction causes a rise in CO and HC emissions and a drop in NOx values for fixed lambda