A Technical Review on Performance and Emission Characteristics of Diesel Engine Fueled with Straight Vegetable Oil

Abstract

As energy reserves are depleting day by day and the environment is polluted, finding an alternative to fossil fuel has become an essential task for the world community. Green fuel (straight vegetable oil) has been found to be a capable alternative to fossil fuel in many applications. Using unprocessed unblended straight vegetable oils (UUSVOs) as a fuel for diesel engine is advantageous in minimizing the processing time, energy, and cost associated with biodiesel production. However, the higher viscosity of vegetable oils limits their long-run use in diesel engine. A planned methodology is, however, required to resolve the issues of poor engine performance and affected emission parameters. This article aimed to present a critical review of the impact of UUSVOs on the performance and emission level of diesel engine during short and long-run engine operations. The crucial aim of this article is to find an eco-friendly alternative to fossil fuel that may serve the world community. The recent literature review shows that straight vegetable oils (SVOs) may become an excellent alternative to diesel engines during short-run operations. However, long-run operation with SVOs as a fuel creates many problems related to damage and maintenance of the engine parts, deteriorated engine performance, significant variation in emission, chocking of injector and fuel line, degraded lubricating oil quality, etc. Engine performance can be improved through the optimization of operation parameters and fuel preheating prior to the injector.