RCCI Engine: Performance and Emission Testing Using Biodiesel

Abstract

With dwindling fossil fuel reserves and rising energy demands, the need for renewable alternatives is more critical than ever. This study explores the potential of Karanja biodiesel, a fuel derived from Karanja oil, as a sustainable replacement for diesel in RCCI engines. Karanja biodiesel offers several advantages. It's renewable, reduces dependence on fossil fuels, and produces lower emissions compared to traditional diesel. This research investigates how Karanja biodiesel blends impact the performance and emissions of an RCCI engine compared to pure diesel. The study converted Karanja oil into biodiesel using a transesterification process with a catalyst and alcohol. Researchers then analyzed engine performance factors like fuel efficiency (brake thermal efficiency or BTE) and fuel consumption (brake specific fuel consumption or BSFC) under varying conditions. This included different compression ratios (16:1, 17:1, and 18:1) and various load levels. An important aspect of the RCCI setup involved injecting gasoline into the intake port of a standard diesel engine. The amount and timing of this gasoline injection were adjusted (3 ms to 5 ms) while using B20 biodiesel for direct injection in a single-cylinder engine. Readings like engine performance and emissions data were collected using a computer interface, a smoke meter, and a 5-gas analyzer. The key finding is that RCCI engines fueled with Karanja biodiesel blends generate significantly lower NOx emissions compared to pure diesel. This translates to cleaner engine operation. However, the most exciting outcome is the substantial improvement in BTE, signifying greater fuel efficiency. BTE for the RCCI engine increased from 31% at a compression ratio of 16:1 to a peak of 35.9% at 18:1 with 5 ms gasoline injection. Additionally, Karanja biodiesel blends showed lower SFC values at maximum load, indicating reduced fuel consumption. These findings strongly suggest that Karanja biodiesel is a highly promising sustainable alternative to diesel fuel for RCCI engines. Its potential for improved fuel efficiency and reduced emissions makes it a viable candidate for a cleaner transportation future.