Patent ID: 9309818
Filing Date: 2016-04-12
CPC Classification: F02D,Y02T

Claim Text:
1. A method of controlling operation of a spark-ignition internal-combustion engine comprising at least one combustion chamber and able to use a single-fuel or a multi-fuel combustion mode with two fuel types comprising at least one fuel type comprising a high octane number and a low energy density and at least another fuel type comprising a low octane number lower than the high octane number of the at least one fuel and a high energy density higher than the low energy density of the at least one fuel, a method wherein the energy required for the engine to operate in single-fuel mode is provided either by the at least one fuel type or by the at least another fuel type and wherein the energy required for the engine to operate in multi-fuel mode is provided by a combination of the two fuels, characterized in that, for engine operation in multi-fuel mode, the method comprises the steps of: determining the set values of the overall energy density and of the overall octane number resulting from the combination of the two fuels, feeding into the combustion chamber the two fuels with a proportion intended to reach the set values, evaluating the real values of the overall energy density and of the overall octane number of the two fuels, in case of a difference between the set values and the real values, in compensating for this difference by varying the proportion of at least one of the two fuels so as to obtain the set energy density and octane number.