Combustion and emission characteristics of di compression ignition engine operated on jatropha oil methyl ester with different injection parameters

Abstract

The current paper reports the engine performance, combustion and emissions from a direct injection compression ignition engine operated with different injector opening pressure (IOP) and injection timing (IT) with jatropha oil methyl ester (JOME) (B100), B20 (20% biodiesel and 80% petroleum diesel fuel which are generally called of B20 fuel) and diesel as test fuels. The engine was run on three different IOP viz. 180, 220 and 240bar along with normal IOP 200bar and two IT viz. 20deg. bTDC and 26deg. bTDC along with normal IT 23deg. bTDC. For all IOP and IT tried, the performance parameters such as brake thermal efficiency (BTE), brake specific energy consumption (BSEC), combustion parameters such as peak cylinder pressure, peak heat release rate and ignition delay and emissions such as UBHC, smoke opacity and NOx are reported here. From the experimental investigations it is observed that IOP 220bar and IT 26deg. bTDC showed better performance for all the test fuels. On the other hand, the performance, combustion and emission characteristics of B20 blend fueled direct injection compression ignition engine performed better for entire load range of operation. At higher loads with IOP 220bar and IT 26deg. bTDC emissions such as smoke opacity and UBHC were observed to be lower compared to other IOPs and ITs. But, NOx emission at retard IT 20deg. bTDC was very low compared to other two ITs. BTE of blend B20 fueled compression ignition engine has increased by 1.01% when operated with IOP 220bar at IT 23deg. bTDC and 1.34% with IT 26deg. bTDC at IOP 200bar. On other hand blend B20 fueled direct injection compression ignition engine showed better performance with reasonable higher brake thermal efficiency and lower BSEC, better combustion and emission when compared to biodiesel (B100) and diesel fuel.