Torgas condensate combustion in the SI engine

Abstract

The article presents results from IC engine tests on combustion of alcohol fuel with the addition of torgas condensate. Torgas is a by-product created from the torrefaction of Sida hermaphrodita. It was obtained from torrefaction carried out at a temperature of 400°C. Torgas was condensed in a tubular cooler. The basic fuel was butanol. This fuel was chosen, because regular hydrocarbon based fuels got delaminated while blended with torgas condensate. The condensate dissolves in alcohol therefore the choice was justified. In the mixture, the volume ratio of alcohol to condensate was 4:1. The combustion was carried out in a spark-ignition, single-cylinder engine with a cubic capacity of 650 cm3. The engine was able to vary its compression ratio. The engine worked at full load at maximum open throttle. The engine body was heated to a temperature of 95°C and this temperature was maintained throughout the testing period. The engine was running at 850 rpm. The first stage of the experiment included determination of the optimal ignition angle for butanol as a reference fuel and for a mixture of butanol and torgas condensate. The optimal spark angle was estimated based on the maximum indicated work. Three compression ratios, i.e.: CR=8.8, 10 and 11.2 were used. All tests were performed for a stoichiometric air fuel ratio. The obtained in-cylinder pressure diagrams for the reference fuel and the fuel with the addition of condensate were compared with each other. The rate of pressure increase inside the cylinder was calculated. For all tests, the following exhaust components were measured: CO2, CO and HC