Experimental investigations of a single cylinder four stroke diesel engine using modified piston bowl fuelled with Jojoba biodiesel blend

This investigation deals with the influence of squish on the piston bowl in single cylinder 4 S compressed ignition engine fuelled with jojoba biodiesel and its effect on performance, emission and combustion characteristics. The squish area and its corresponding velocity are varied by changing the piston bowl cross-section without altering the piston bowl volume so as to obtain improved performance, emission and combustion characteristics. The velocity and squish effects are analyzed using CFD (Computational Fluid Dynamics) for the standard piston. The results obtained are compared with the modified piston having an octagonal bowl shape in the piston combustion chamber. The performance and combustion characteristics like brake specific fuel consumption, brake thermal efficiency and pressure vs. crank angle and heat release rate are studied. Also, emission parameters such as (carbon monoxide), HC (hydrocarbons) and NOx (oxides of nitrogen) were measured from the tail end of the exhaust pipe. The objective of this work to optimize the combustion chamber geometries using octagonal bowl combustion chamber and the results are compared with the standard hemispherical combustion chamber. A significant increase in brake thermal efficiency is noticed for octagonal piston bowl. There is a reduction in HC, CO which are seen while using octagonal bowl piston compared with the standard piston. (c) 2019 Elsevier Ltd. Selection and Peer-review under responsibility of the scientific committee of the International Mechanical Engineering Congress 2019: Materials Science.

Automated summary

This study investigated the influence of squish on the piston bowl in a single cylinder 4S compressed ignition engine fueled with jojoba biodiesel. By varying the squish area and corresponding velocity, improved performance, emission, and combustion characteristics were obtained without changing the piston bowl volume. The use of an octagonal bowl piston showed significant increases in brake thermal efficiency, and reductions in HC and CO emissions compared to a standard piston.