A Theoretical Approach to the Combustion of Fuel-Alcohol Blends

This paper is concerned with the results of a theoretical investigation on combustion of traditional fuel and alcohol blends. An analytical procedure has been developed which examines three different hypotheses for introducing the alcohol: constant mass of primary fuel, constant total energy of fuel, and constant total mass of fuel. The procedure has been applied to combustion at constant volume varying over a wide range of air-fuel ratios, percentage of alcohol, and combustion temperature. The results obtained, of particular interest for reciprocating internal combustion engines, indicate that as far as energy and emissions are concerned, the effects of alcohol on combustion depend strongly on the hypothesis adopted for fueling the alcohol.