Analysis of EGR Coupled Less Heat Rejection Model of Diesel Engine with Blends of Jatropha Biodiesel, Diesel and Diethyl Ether: An Experimental Approach

Abstract

The experimental investigation on a less heat rejection model (LHRM) of the diesel engine was done with the objective to improve the performance and emission characteristics. The LHRM has a bond coat of NiCrAl interposed between the thermal barrier ceramic coated cylinder head and liner of the engine. The model is coupled with exhaust gas recirculation (EGR) system at a constant rate of 10 vol.%. The test fuels are neat diesel for the non-coated engine (NCE) and blends with different ratios of dieselJatropha biodiesel, keeping a constant ratio of additive diethyl ether (DEE) for the LHRM. The load was varied from 0 to 100 % and injection timing (IT) from 29° to 34° BTDC.The performance parameters of both engines improved significantly with the advancement of the injection timing. The NOx emissions reduced with no effect on
BSEC, BTE and smoke levels with 10 % EGR rate. The optimum blend and IT for LHRM are D20JB60A20 by vol. (20 % of diesel + 60 % of Jatropha biodiesel + 20 % of additive DEE) and 32° BTDC as the maximum enhancement of about 6 to 7 % in peak BTE with a reduction in BSEC by 9.5 %, EGT by 18 %, VE by 2 to 3 %, smoke level by 44.5 % and NOx emissions by 14.2 % were found compared to NCE with diesel at normal
operating conditions. At advanced injection timings with a higher load, in comparison to NCE, LHRM showed significant improvement in all of the investigated parameters.