METHOD FOR FAST DETERMINATION OF BASIC IC ENGINE CHARACTERISTICS AT DIFFERENT FUELS USE

A permanent race for achieving low pollutants emissions in exhaust gases from the IC engines is characterized by introduction of new technical and technological solutions in fuel injection systems, improvement of combustion process, after treatment of exhaust gases, as well as the use of alternative fuels. An advantage in use of alternative fuels with IC engines for motor vehicle propulsion has fuels which do not require greater modifications of the IC engines. In this scope, bio fuels and LPG are the best fuels, especially LPG where good supply infrastructure exists. Use of petrol and LPG fuels operated IC engines, simultaneously, represents the best solution for powering of the motor vehicles. Besides ecological aspects, the most important parameter for additional setting of LPG installation is economical, due to price of this fuel which is significantly lower when compared to petrol. Although manufacturers of LPG systems offer a swift change of petrol to LPG use on IC engines and viceversa, a question on how LPG system influences the basic IC engine characteristics could be asked. Results of research related with the basic IC engine characteristics in case of petrol and LPG use, for pointed vehicle, are presented in the paper. In order to determin mentioned engine characteristics, the measurements of vehicle dynamics characteristics was carried out and afterwords the determination of the IC engine characteristics was done by calculation. The decisive role on these characteristics has the way of introduction of LPG in the combustion chamber and setting of system’s parameters. 1