INFLUENCE OF BIOFUELS ON DIESEL ENGINE PERFORMANCE

In principle, emission reduction of toxic substances in exhaust gas of IC diesel engines can be achieved at three places: before, in and after the IC engine. The common approach is the introduction of catalytic exhaust systems, valve timing, fuel mixture preparation and combustion modeling, as well as using fuels the chemical composition of which provides the potential for reduction. The latter option seems to be the simplest, but it is not necessarily the first option that would be taken into consideration. Due to the different properties of fuels, it is necessary to optimize individual systems of the internal combustion engine; otherwise, it may happen that the reduction of emissions of toxic substances is absent as a desired effect, or, in the opposite extreme, unacceptable performance of the engine may result. This paper provides an elaboration on the use of bio fuels in the form of rapeseed methyl esters - bio diesel, in terms of performance and the need for optimization of individual systems on internal combustion engines. That is a precondition for the effective use of bio fuels as the only fuel, and there is also a possibility of optimizing the engine system in order to achieve the best possible relative performance in case both fossil fuel and bio fuel are used.