Enhancing Liquefied Petroleum Gas utilization in Compression-Ignition engine powered with Renewable Fuel under Dual Fuel concept- An Experimental Study

ABSTRACT

The current research article aims at improving LPG (Liquefied Petroleum Gas) utilization in a compression ignition engine powered with renewable fuel namely Calophyllum inophyllum biodiesel (CPBD). The combustion, performance and emission tests were conducted in the stationary single-cylinder water-cooled engine at a constant speed of 1500 rpm. The engine was remodeled to function in a dual fuel mode utilizing LPG as primary fuel and CPBD as pilot fuel. Through suction stroke, the primary fuel was supplied whereas the CPBD was injected through direct injection. The results show that the CPBD improved the performance of the engine under the LPG-based dual-fuel engine. There was an increase observed in Brake thermal efficiency (BTE) of CPBD upto 4.9% under LPG mode with 12% LPG energy share and a drop in BTE limited with LPG substitution. The water injection method was attempted in this research to increase the substitution of LPG, which resulted positively. The 5% water injection (5%W) increased the LPG substitution from 12% to 16% with a 7% improvement in BTE. There was a drastic improvement noted in hydrocarbon (HC) and Carbon Monoxide (CO) emission in dual fuel mode. The HC emission got decreased by 37.14% in CPBD+LPG mode to 45.7% in CPBD+LPG+5%W mode. Similarly, the CO emission got decreased by 65% with CPBD+LPG mode to 64% with CPBD+LPG+5%W mode. Likewise, the smoke emission also got decreased by 87% in CPBD+LPG mode to 74% in CPBD+LPG+5%W mode. However, NO emission got drastically increased by 90% and 85% in CPBD+LPG and CPBD+LPG+5%W respectively. To conclude, CPBD can be effectively used in CI engines under LPG-based dual fuel mode, which improves the performance and emission concurrently.

KEYWORDS:

• LPG
• dual fuel engine
• biodiesel
• pollution control
• diesel

Abbreviations and nomenclatures

LPG	=	Liquefied Petroleum Gas
BTE	=	Brake thermal efficiency
CPBD	=	Calophyllum Inophyllum biodiesel
HC	=	Hydrocarbon emission
CO	=	Carbon monoxide emission
NO	=	Nitric oxide emission
5%W	=	5% water injection by mass basis
CPBD+LPG	=	Dual fuel mode with CPBD as pilot fuel and LPG as the primary fuel
CPBD+LPG+5%W	=	Dual fuel mode with CPBD as pilot fuel and LPG as primary fuel with water injection
LPM	=	Litre per minute
CA	=	Crank angle
FTIR	=	Fourier-transform infrared spectroscopy