Effect of Compression Ratio on Emission of CI Engine using Neat Karanja Oil and Karanja Oil Methyl Ester Blends

The standard design parameters of a compression ignition engine fail to give specified performance with strait vegetable oil (SVO) from different origins. This study is performed to find the effect of compression ratio on emission characteristics such as carbon monoxide (CO), carbon dioxide (CO2), hydrocarbon (HC), nitrogen oxides (NOx) and smoke opacity with all the tested fuels in a single cylinder, four stroke VCR engine fueled with neat Karanja oil blends (10% and 20%)  with diesel (on volume basis) and Karanja oil methyl ester (KOME) blends (20%, 40% and 60%) and the results are compared with  diesel. Experiment has been conducted at compression ratios of 16:1, 17:1, 18:1. At higher CR minimum value CO is recorded 0.04% for 20% blend of KOME (B20), while it show maximum CO2 recorded 4.45%. Lowest HC and NOx emission recorded 22 ppm and 552 ppm respectively for 40% blend of KOME (B40). Emissions are marginally higher for K10 and K20 than diesel. Overall observation shows that B40 shows lowest emissions than other blends of KOME at higher compression ratio.