Improvement in performance of CI engine using various techniques with alternative fuel

As a renewable, sustainable, and alternative fuel for combustion ignition (CI) engines, researchers are more prone to accept biodiesel as fuel compared to diesel. Auto-ignition, as well as decomposition reactions, significantly rely on spray characteristics and air-fuel mixing in conventional diesel engines. While the accumulation of fuel-rich mixture in the combustion chamber, also strongly responsible for lesser performance and emissions of carbon mono oxide (CO), hydrocarbon (HC), nitrogen oxide (NOx), and particulate matters (PM) of the diesel engine. CI engines running on alternative fuels (AFs) such as biodiesel, vegetable-based fuels do not meet satisfactory performance due to higher rheological properties and lower heating value. Strict emission regulation from CI engines has transferred the conventional combustion to advanced combustion by intending to lower harmful emissions. Thus, this is the mandate to question what are the techniques and modification which may improve the performance and emissions from a diesel engine. In this article, the effect of noncircular orifices were assessed to analyze the atomization and air-fuel mixing of fuel and their impact on performance and emissions. The advantages and disadvantages of modification in the intake manifold, injection parameter, and fuel modification were thoroughly analyzed based on performance and emissions. In the end, this is worth to note that noncircular orifices especially elliptical orifice imparted better atomization and fuel-air mixing than a circular orifice. In addition, air swirl through guide vanes in the intake manifold exhibited several benefits. It revealed an increase in thermal efficiency and reduced NOx than nonswirling in a diesel engine.