Increasing global environmental issues and depleting fossil fuel reserves has necessitated the need for alternative and sustainable fuel. In this paper, the effects of biodiesel and its blend on engine emission and performance characteristics in an internal combustion engine were analyzed. Biodiesel derived from the transesterification of raw palm oil was blended with diesel fuel at different proportions designated as PO5 (5% Biodiesel and 95% Diesel), PO10 (10% Biodiesel and 90% Diesel), PO15 (15% Biodiesel and 85% Diesel), PO20 (20% Biodiesel and 80% Diesel), PO50 (50% Biodiesel and 50% Diesel), PO85 (85% Biodiesel and 15% Diesel), and PO100 (100% Biodiesel). A Lombardini 2-cylinder, four-stroke direct injection diesel engine with a compression ratio of 22.8 was developed using Ricardo Wave software in which diesel, palm oil biodiesel blends and pure biodiesel are used in the model, and the obtained results were analysed and presented. The simulation was done under varying engine speeds of 1200 rpm to 3200 rpm at full load condition. Biodiesel and its blends are more environment-friendly and non-toxic when compared to diesel fuel; it also improves the mechanical efficiency of the engines, and above all can also lead to a reduction in poverty among rural dwellers. The obtained results showed that brake specific fuel consumption and brake thermal efficiency increased with palm oil biodiesel blends as compared to diesel fuel which might be a result of biodiesel's lower heating value, and the increase in thermal energy may be a result of the oxygenation of the biodiesel blend as compared to pure diesel. In terms of brake torque, palm oil biodiesel blends were lesser than diesel fuel. The CO, HC, and NO x emissions of palm oil biodiesel blends decreased significantly compared to that of pure diesel. From this study, palm oil biodiesel emits lesser emissions than diesel fuel and its performance characteristics are similar to diesel fuel. Therefore, palm oil biodiesel can be used without any modifications directly in a diesel engine.

With their higher sustainability index, biofuels, environmentally-friendly and renewable nature is a viable alternative energy source in the transportation sector. This study presents the effect of waste cooking oil (WCO) biodiesel on performance, combustion, and emission from a compression ignition engine. The biodiesel was blended with diesel in varying proportions of 5% biodiesel and 95% diesel (designated as B5), 10% biodiesel in diesel (B10), 15% biodiesel in diesel (B15), 20% biodiesel in diesel (B20), 50% biodiesel in diesel (B50), and 85% biodiesel in diesel (B85). Simulation of a 2-cylinder diesel engine fueled with diesel, biodiesel blends and pure biodiesel was carried out using Ricardo Wave software and the results obtained were validated. The engine speed was varied from 1200 rpm to 3200 rpm at full load condition using a positive valve overlap of 32°. Performance results showed that WCO biodiesel blends at 1200 rpm produce brake-specific fuel consumption of, 0.240109 kg/kWhr, 0.241996 kg/kWhr, 0.244331 kg/kWhr, 0.24661 kg/kWhr, 0.26089 kg/kWhr, 0.27947 kg/kWhr and 0.28798 kg/kWhr for B5, B10, B15, B20, B50, B85 and B100 respectively, as compared to 0.239383 kg/kWhr of diesel fuel while the brake power and torque reduced at full load with varying speed. Combustion analysis showed similar trends between diesel and biodiesel blends whereas biodiesel blends produced shorter ignition delay, shorter combustion duration, and lower heat release rate. Emission levels of CO, reduced by 1%, 10%, 15%, 22%, 48%, 68% and 74% with B5, B10, B15, B20, B50, B85 and B100 respectively at 1600 rpm when compared to diesel fuel. HC emission was reduced by 9% with B100. NO_x levels slightly increased when B5, B10, B15, and B20 at 1200 rpm and B10 and B15 at 1600 rpm were fueled in the engine. The exhaust gas temperature (EGT) of B5, B10 at 1600 rpm was higher than diesel fuel and B5, B10 at 2400 rpm to 3200 rpm EGT was higher than diesel fuel. Generally, biodiesel blends showed better emission levels and other combustion and performance levels are within acceptable limits.

Increasing global environmental issues and depleting fossil fuel reserves has necessitated the need for alternative and sustainable fuel. In this paper, the effects of biodiesel and its blend on engine emission and performance characteristics in an internal combustion engine were analyzed. Biodiesel derived from the transesterification of raw palm oil was blended with diesel fuel at different proportions designated as PO5 (5% Biodiesel and 95% Diesel), PO10 (10% Biodiesel and 90% Diesel), PO15 (15% Biodiesel and 85% Diesel), PO20 (20% Biodiesel and 80% Diesel), PO50 (50% Biodiesel and 50% Diesel), PO85 (85% Biodiesel and 15% Diesel), and PO100 (100% Biodiesel). A Lombardini 2-cylinder, four-stroke direct injection diesel engine with a compression ratio of 22.8 was developed using Ricardo Wave software in which diesel, palm oil biodiesel blends and pure biodiesel are used in the model, and the obtained results were analysed and presented. The simulation was done under varying engine speeds of 1200 rpm to 3200 rpm at full load condition. Biodiesel and its blends are more environment-friendly and non-toxic when compared to diesel fuel; it also improves the mechanical efficiency of the engines, and above all can also lead to a reduction in poverty among rural dwellers. The obtained results showed that brake specific fuel consumption and brake thermal efficiency increased with palm oil biodiesel blends as compared to diesel fuel which might be a result of biodiesel's lower heating value, and the increase in thermal energy may be a result of the oxygenation of the biodiesel blend as compared to pure diesel. In terms of brake torque, palm oil biodiesel blends were lesser than diesel fuel. The CO, HC, and NO x emissions of palm oil biodiesel blends decreased significantly compared to that of pure diesel. From this study, palm oil biodiesel emits lesser emissions than diesel fuel and its performance characteristics are similar to diesel fuel. Therefore, palm oil biodiesel can be used without any modifications directly in a diesel engine.