AN IMPACT OF INJECTION PRESSURE ON OPERATING CHARACTERISTICS OF A DIESEL ENGINE FUELED WITH GARCINIA GUMMI-GUTTA BIODIESEL

• Date: 2026
• Main Authors: Sekharraj, K., Balu, P., Subramanian , M., Vasanthkumar, P., Didkivska , G.
• Format: Article
• Language: English
• Published: Institute of Renewable Energy National Academy of Sciences of Ukraine 2026
• Subjects: Diesel engine; Garcinia Gummi-Gutta; High-pressure injection; Performance; Emissions; combustion.
• Online Access: https://ve.org.ua/index.php/journal/article/view/646
• Journal Title: Vidnovluvana energetika

The current study assesses the effect of injection pressure on the performance of a single-cylinder direct injection diesel engine running on biodiesel extracted from Garcinia gummi-gutta. The experiments were carried out on diesel, B20 (20% biodiesel and 80% diesel), B20 with Hemispherical Combustion Chamber (HCC), and B20 with Toroidal Re-entrant Combustion Chamber (TRCC) at standard injection pressure of 200 bar. At full load, the brake thermal efficiency (BTE) of diesel was found to be 32.8%, whereas that of B20 was 30.9%. The use of HCC increased BTE to 31.6%, whereas B20+TRCC at standard pressure increased BTE to 33.4%, which is a clear indication of better air-fuel mixing and turbulence. Further change in injection pressure for TRCC configuration showed that at 180 bar, BTE was 32.1% with brake specific fuel consumption (BSFC) of 0.282 kg/kWh; at 200 bar, BTE increased to 33.4% with 0.268 kg/kWh; at 220 bar, maximum efficiency was attained with 34.6% BTE and 0.254 kg/kWh; and at 240 bar, BTE slightly dropped to 34.2% with 0.259 kg/kWh. Analysis of the emission revealed that CO emission reduced from 0.42% (diesel) and 0.38% (B20) to 0.24% at 220 bar, while HC emission reduced from 54 ppm to 38 ppm and smoke opacity reduced from 58 HSU to 44 HSU. But NOx emission increased from 842 ppm (diesel) to 910 ppm at 220 bar due to increased peak temperatures. Maximum cylinder pressure also increased from 67 bar (B20 standard) to 72 bar at 220 bar injection pressure. Thus, the B20+TRCC combination at 220 bar had the optimal trade-off between efficiency enhancement and emission control, thereby establishing the suitability of Garcinia gummi-gutta biodiesel in compression ignition engines.