The Journal of Science and Engineering Applications (JSEA)

Abstract

This paper reviews Variable Compression Ratio (VCR) technology in detail and critically evaluates its effects on the performance, combustion, and emission characteristics of diesel engines. The review systematically synthesises findings on the technology's compatibility with a variety of renewable fuels. The novelty of the present work lies in filling a critical research gap: integrating Liquefied Petroleum Gas (LPG) as a dual fuel with diesel and hybrid nanoparticles in VCR engines. It is shown that the use of VCR technology improves thermal efficiency and reduces fuel consumption at low loads and reduces nitrogen oxide (NOx) emissions at high loads, but the synergistic benefits of VCR technology with advanced fuel-nanoparticle combinations remain largely unexplored. The review points out future opportunities for improving diesel engine efficiency and emissions by utilizing LPG-diesel dual fuel operation and nanoparticle additives in VCR systems.