Abstract
Keywords:
LPG, Knock Control, Octane Number.
Abstract
LPG is an alternative fuel that is friendlier to the environment since it does not contain lead. Furthermore, LPG has a high Octane Number that makes it desirable for high compression engines. These two features of LPG are used in this research by using LPG mixed with low octane fuel (Premium) to obtain higher octane fuel without the addition of harmful lead content. In addition, in this research, LPG is also used to control knock. The engine’s characteristics were studied in this research when Premium or LPG was used. The results give further information on how LPG can be used to control knock. To control knock, a Programmable Ignition Timing Controller and a Programmable Fuel Duration Controller were constructed for this research. Both controllers were used control the ignition timing, the amount of gasoline and the flow of LPG, and to obtain the knock signal. Since many problems were encountered with the brake dynamometer, experiments could only be done at ¼ and open throttle. The results of testing with gasoline and LPG fuels show promise on the use of LPG as a knock controller. When knock control is used by using LPG, the system could introduce LPG when knock occurs. Several methods introducing LPG and cutting of the gasoline were exercised and the best method was found. The system was able to shut down gasoline and opens the LPG line in a certain strategy when knock occurs in the engine.