Enhancing combustion, performance and emission profiles using kapok methyl ester blends with hydrogen

This study investigates the potential of using a dual green alternative fuel combination, the one is hydrogen fuel and another one is biodiesel for enhancing the Combustion, performance and emission characteristics of a compression ignition engine. The kapok oil methyl ester was blended with diesel in proportions of 20% (K20) and 40% (K40) by volume. The hydrogen gas was supplied at a constant flow of 4 liter per minute (LPM). The experimental fuels are neat diesel D100, K20 (80% Diesel and 20 % kapok methylester), K40 (60% Diesel + 40 % Kapok methyleter), K20 + H4L (K20 with 4 LPM hydrogen) and K40+H4L (K40 with 4 LPM hydrogen). These blends were tested in a single cylinder direct injection diesel engine under different load conditions at a constant speed of 1500 rpm, combustion, performance and emissions characteristic were evaluated and compared with base fuel. The results indicated that te use of B20 and B40 blends without hydrogen led to reduced brake thermal efficiency due to their lower cetane number and calorific value. Additionally, higher viscosity of the blends resulted in increased brake specific fuel consumption. However the introduction of hydrogen and kapok biodiesel also led to a substantial reduction in carbon monoxide and carbon dioxide emissions, attributed to improved combustion facilitated by the higher oxygen content of the biodiesel. Nonetheless, no significant reduction in nitrogen oxides emissions was observed across the tested blends compared to neat diesel.