Abstract
Farming tractors consume the most share of diesel fuels in agricultural sectors. As most engine tests are performed in engine laboratories, the study aims to examine the effect of biodiesel, diesel, and ethanol blends in actual farming conditions. Accordingly, the percentage of ethanol and biodiesel and the gear (forward speed) were considered the independent variables. The output variables were the slippage percentage, traction efficiency (TE), and emission factors. It was found that B2E7 (2% biodiesel including 7% ethanol) provided the lowest slippage percentage in comparison with control (about 15, 17 and 19% respectively for L1 (low gear 1), L2 (low gear 2) and L3 (low gear 3)). On average, increasing the gear level increased the slip percentage by about 8 and 14% for L2 and L3 compared to L1, respectively. Also, increasing forward speed (increasing gear from L1 to L3) reduced the traction efficiency. The maximum traction efficiency was obtained at B2E7, followed by B5E7, which were, on average, about 3 and 3.5% higher than the control, respectively. The optimization results indicated that the highest performance and the lowest emission were obtained using a fuel with a formulation of 0.2% ethanol and 4.1% biodiesel (B4.1E0.2) at L3.