Optimization of fuel injection parameters and compression ratio of a biogas fueled diesel engine using methyl esters of waste cooking oil as a pilot fuel

The present study aims to run a diesel engine completely with renewable source, which is biogas and waste cooking oil methyl ester (assumed when cooking methods not changed) on a dual fuel mode. Further, this study also attempts to unfold the combined effect of both fuel injection parameters and compression ratio on its performance, and combustion analyses of a diesel engine, modified to run on biogas-biodiesel. A series of tests were conducted by considering three different parameters (injection timing, injection pressure and compression ratio (CR)) at three different levels. i.e., injection timing advanced to 3 degrees CA from standard 23 degrees CAbTDC, injection pressure increased to 240 bar from standard 200 bar, one higher and one lower compression ratio from standard CR17.5. The results obtained were compared with the diesel at engine's original settings (CR17.5, 23 degrees CAbTDC, 200 bar and 4.4 kW). It was found that, the combination of CR18.5, 240 bar injection pressure and 24.5 degrees CAbTDC gave a maximum BTE of about 31.2%. At the same condition, HC, CO and smoke emissions were found to be lesser by 55.5%, 3.5% and 19.1% respectively than diesel at full load. However, for the same CR and 240 bar, advancing from 24.5 degrees CAbTDC to 26 degrees CAbTDC resulted in a poor performance. (c) 2021 Elsevier Ltd. All rights reserved.

Automated summary

This study aims to run a diesel engine completely with renewable sources such as biogas and waste cooking oil methyl ester. The research investigates the combined effect of fuel injection parameters and compression ratio on the performance of a modified diesel engine running on biogas-biodiesel. Results showed that specific parameters led to improved fuel efficiency and reduced emissions compared to a standard diesel engine.