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

Numerical analysis of a gas turbine combustor fueled by hydrogen in comparison with jet-A fuel

The interest in alternative fuels has increased in recent years. Because, the conventional fuels have the danger of extinction in the near future and these fuels harm the environment. Therefore, in this study, the availability of hydrogen as an alternative fuel has been investigated in the tubular combustion chamber of a gas turbine engine fueled by jet-A fuel. For this purpose, the combustion characteristics in the combustor of a Rolls-Royce Nene turbojet engine fueled by gas jet-A and hydrogen have been numerically studied at different excess air ratios (EAR) for a given thermal power values. Temperature distributions in the combustor, combustion efficiency, pressure drop and velocity change have been numerically analyzed at 1480 kW (10000 rpm), 2290 kW (11000 rpm) and 2980 kW (12000 rpm) thermal power in the combustion chamber. The RNG k-turbulence and eddy-dissipation combustion models have been used for 2D axisymmetric geometry with swirling flow

Effects of compression ratio on performance and emissions of a modified diesel engine fueled by HCNG

In this study, the effects of compression ratio (CR) have been investigated engine performance and emissions characteristics of a modified diesel engine fueled by HCNG (hydrogen enriched compression natural gas) blends (100% CNG, 95% CNG +5% H-2, 90% CNG + 10% H-2 and 80% CNG + 20% H-2). The experiments have been carried out using a modified Isuzu 3.9 L diesel engine having 9.6, 12.5 and 15 different compression ratios at 1500 rpm under full load conditions. Engine brake torque, brake specific fuel consumption, combustion analysis and emissions parameters (CO, THC and NOX) have been realized at 10 CA BTDC ignition timing and different excess air ratios (lambda = 0.9-1.3)