Impact of high blends of Madhuca Logifolia biodiesel on the performance, combustion and emission parameters in a CRDI diesel engine at variable compression ratio

The country today uses a variety of industrial and transportation facilities that are fueled by diesel fuel. However, because of its non-sustainable and polluting nature, there is an urgent need for a more environmentally acceptable substitute that can be utilized in existing engines with no or little modification. Madhucalongifolia (Mahua) was considered a main source for biodiesel production based on its availability and its nature to not impact the food chain. The raw oil was converted to biodiesel using the process of transesterification. The higher blends of B80 (80% mahua biodiesel, 20% diesel by vol.) and B90 (90% mahua biodiesel, 10% diesel by vol.) were prepared. The experiment was carried out using an eddy current dynamometer and involved a Kirloskar 4-stroke single-cylinder which was water-cooled, CRDI diesel engine. The base run was generated using 18:1 compression ratio diesel fuel. These outcomes were contrasted with identical engine conditions using blends of B80 and B90 biodiesel as fuel. The most favourable results in terms of the engine parameters ie. BTE, SFC, cylinder pressure, HC, NOx and CO were as stated here. There was an increase of 8.87% in BTE for the B90 blend. A minor increase of 2.77% in SFC was observed with the B90 blend. The cylinder pressure for B90 was decreased by 0.024%. The emissions for B80 and diesel were lesser in comparison to B90. Diesel showed the lowest CO (7.9%) emissions whereas HC and NOx for B80 decreased by 24.39% and 3.42% respectively. The engine was made to run at two lower compression ratios of 16 and 17. When using a fuel blend of B80 at a compression ratio of 16, the performance metrics were significantly better. It could be concluded that, the compatible results were found with B80 biodiesel blend with compression ratio of 16. The BTE, SFC, cylinder pressure, HC, NOx and CO were quantified as 25.61%, 0.34kg/kWh, 30.27 bar, 50ppm, 1204 ppm and 0.24% by volume respectively. In comparison to the base run (diesel fuel and compression ratio of 18), there was 15.98% increase in the BTE, 5.55% decrease in the SFC, 16.07% decrease in the cylinder pressure, 21.95% decrease in the emission of HC, 23.55% decrease in NOx and 9.09% increase in CO emissions.