Particulate Emissions From Karanja Biodiesel Fuelled Turbocharged CRDI SUV Engine

Abstract

The use of biodiesel substantially reduces particulate matter (PM), hydrocarbon (HC) and carbon monoxide (CO) emissions, slightly reduces power output; increases fuel consumption and marginally increases oxides of nitrogen (NOx) emission in an unmodified common rail direct injection (CRDI) diesel engine. Lower blends of biodiesel demonstrated lower emissions, while easing pressure on scarce petroleum resources, without significantly sacrificing engine power output and fuel economy. However due to adverse health effects of smaller size particulate matter (PM) emitted by internal combustion (IC) engines, most recent emission legislations restrict the PM mass emissions in addition to total particle numbers emitted. It is an overwhelming argument that usage of biodiesel leads to reduction in PM mass emissions. In this paper, experimental results of PM emissions using Karanja biodiesel blends (KB20 and KB40) in a modern CRDI transportation engine (maximum fuel injection pressure of 1600 bar) have been reported. This study also explores comparative effect of varying engine speed and load on PM emissions for biodiesel blends vis-à-vis baseline mineral diesel. Particulate size-number distribution, particle size-surface area distribution and total particulate number concentrations were experimentally determined under varying engine operating conditions and compared with baseline mineral diesel. KB20 showed highest particulate number concentration upto 80% rated engine loads, however at rated load, KB40 emitted highest number of particulates.