Combustion and exhaust emissions study in a single-cylinder four-stroke diesel engine with swirl augmentation techniques

ABSTRACT

Experiments were conducted to study the effects of injector nozzle geometry, angle of masking, grooves on pistons and grooves and bridges on the cylinder head on the performance of a single-cylinder four-stroke direct injection diesel engine operated with Honge oil methyl ester (HOME). To achieve proper burning of viscous biodiesel (HOME) in a modified diesel engine, injectors with 3–5 holes, angle of masking of 30–90°, 3–9 grooves on piston, and 1–3 bridges and 2–4 grooves on the cylinder head were tried and tests were conducted accordingly. The last three modifications were intended to intensify the swirl for better mixing of fuel and air without altering the compression ratio of the engine. Results showed very low emission levels in terms of carbon monoxide (CO), unburned or partially burned hydrocarbons (HC) and soot emissions, slightly increased nitrogen oxide (NOx) and a significant improvement in performance when the number of injector holes, angle of masking, and grooves on piston and cylinder head were increased up to certain acceptable levels, beyond which the performance was lowered. Introduction of grooves and bridges in a diesel engine has proven to be effective in achieving better engine performance with lower emission levels and could address emission regulations.

KEYWORDS:

• Honge oil methyl ester
• brake thermal efficiency
• inlet valve masking
• nozzle hole
• smoke opacity

Disclosure statement

No potential conflict of interest was reported by the author(s).