ABSTRACT
VCR has been in high volume production since 2019 for SI light duty engines in passenger cars, mainly for CO2 reduction; plus a manufacturer of cathedral style Megawatt marine engines is now offering VCR applications for 2025. The engine industry faces a plethora of low carbon, renewable fuels which are expected to result in increases in cetane and octane variability. VCR, with appropriate sensors and control systems, could make internal combustion engine more omnivorous and less sensitive to fuel variability. This paper reviews VCR systems and anticipated on-costs for several engine categories. The potential role of VCR for extending engine performance capability using a single engine platform is outlined.
