Practical Investigation of Single Cylinder Spark Ignition Engine Performance Operated With Various Hydrocarbon Fuels and Hydrogen

Abstract

Hydrogen, natural gas, and liquefied petroleum gas are the most important alternative fuels for gasoline in spark-ignition engines, for many reasons, such as the large world reserve of these gases, high heating value, high octane number, low emissions emitted from burning them in engines, and their low prices compared with gasoline. This practical study was conducted with these fuels to operate a single-cylinder with variable compression ratio, speed, and spark timing Ricardo E6/US, and its performance was compared with that resulted from operating the engine with gasoline. The results appeared that the HUCR (higher useful compression ratio) for gasoline is 8:1, 10.5:1 for LPG, 13:1 for natural gas, and 11:1 for hydrogen. Results appeared that spark timing is highly advanced when using NG more than other used fuels, because of its low flame speed propagation, on other hand, it is highly retarded when using hydrogen, because of its high flame propagation speed. The study conducted that brake power of LPG and NG is less than that for gasoline at CR=8:1, but they became closer when the engine operated at HUCR for each fuel, while it stayed very little for hydrogen due to its low heating value on a volume basis. The results show that specific fuel consumption for hydrogen is less than bsfc for NG, which is less than that for LPG; gasoline has the higher bsfc on a mass basis. Also, the exhaust gas temperature for hydrogen and NG is found to be less than LPG...