Determination of effects of compression ratio variation on performance and emission characteristics of a diesel engine fueled with EDTA-doped sunflower biodiesel-petrodiesel

Abstract

This experimental study focuses on unraveling the effects of compression ratio(CR) variation on performance and emission characteristics of a variablecompression ratio (VCR) diesel engine under various loads. The engine wasfueled with 100% sunflower biodiesel (B100) and B100 withEthylenediaminetetraacetic acid (EDTA, C10H16N2O8) additive(B100+EDTA), separately, to determine fuel effect. Subsequent todetermination of fuel properties, effects of these two fuels were comparedunder 3 different CRs. High hydrogen and oxygen contents, negligiblechemical inactivity and high cetane number (CN) made EDTA an attractiveadditive for B100 in the context of engine characteristics. It was observed that,B100+EDTA depicted higher average t values of 24.3%, 25.7% and 26.5%whereas they were 17.3%, 18.7% and 19.4% for B100 under CRs of 16, 17 and18, respectively. In terms of BSFC, average B100 values were 17.3, 16.1, 14.8(kJ/kWh) whereas 10.1, 9.2, 7.9 (kJ/kWh) for B100+EDTA under CRs of 16,17 and 18, respectively. Te values were 265ºC, 252ºC and 234ºC forB100+EDTA and 296ºC, 281ºC and 267ºC for B100 at CRs of 16, 17 and 18,respectively. CO values were 110, 103 and 96 (ppm) for B100; 82, 74 and 65(ppm) for B100+EDTA under under in-question CRs. UHC values of 124, 115and 98 (ppm) for B100+EDTA; 141, 134 and 119 (ppm) for B100 wereobtained under CRs of 16, 17 and 18, respectively. CO2 emission values were4.2%, 5.7% and 6.3% (by vol.) for B100+EDTA; 3.4%, 3.9% and 5.1% forB100 under CRs of 16, 17 and 18, respectively. NOx values were 170, 192 and210 (ppm) for B100+EDTA; 104, 126 and 137 (ppm) for B100 under CRs of16, 17 and 18 respectively. Smoke opacity values were 16%, 12% and 10% forB100+EDTA; 21%, 18% and 16% for B100 under CRs of 16, 17 and 18,respectively.