Impact of particulate filters on biodiesel and diesel fuel: a comparative study of thermal efficiency and emissions

• The results showed that using B100 in the engine reduced soot by approximately 59% compared to B7. • The presence of P-DPF and F-DPF resulted in BTE decreasing by 0.07 and 2.62%, respectively. • The P-DPF and F-DPF proved effective at reducing smoke to half and near-zero levels, respectively. This study investigated the influence of a partial-flow (P-DPF) and a full-flow (F-DPF) diesel particulate filter on the combustion and emissions of a light-duty diesel engine fueled with conventional diesel (B7) and pure biodiesel (B100). The engine was operated on a dynamometer under engine speeds of 1600-2000 rpm at 84-140 Nm loads. The results revealed that while B100 had higher mass-based specific fuel consumption (BSFC) due to its lower energy density, its overall brake thermal efficiency (BTE) was comparable to that of B7, indicating similar energy conversion efficiency. The use of DPFs resulted in a modest efficiency penalty, with brake thermal efficiency decreasing by 0.07% for the P-DPF and 2.62% for the F-DPF. The emissions analysis revealed the trade-offs associated with biodiesel use and DPF integration. While baseline B100 operation produced substantially higher nitric oxide (NO) emissions relative to B7, it consistently generated much lower smoke opacity. When averaged across all three aftertreatment configurations (no DPF, P-DPF, and F-DPF), B100 reduced smoke emissions by approximately 59% compared with B7. Additionally, the P-DPF and F-DPF proved effective at reducing smoke to half and near-zero levels, respectively, for both fuels.