Load factor evaluation and emissions calculation for the cultivator under real working conditions

Currently, emission management for agricultural machinery in South Korea only targets diesel engines, leading to insufficient management of gasoline engines. Emission calculations are required to manage emissions, and a load factor (LF) is necessary for these calculations. However, there is currently no standard for the LF for gasoline engines in South Korea. Therefore, the purpose of this study was to measure the engine LF for the small multipurpose cultivator under actual working conditions and evaluate it by comparison with the national Clean Air Policy Support System (CAPSS) of South Korea and the European Environment Agency (EEA) approaches, respectively. A torque sensor capable of collecting torque and rotational speed was installed on the engine output shaft, and a data acquisition board was used to collect data. Field tests were conducted on the main operations of the cultivator, such as idling, rotary tillage, ditching, and ridging operations. Engine power was calculated using engine torque and rotational speed, and LF was calculated using real-time power and rated power. In addition, the unified LF was calculated by using the weight for each operation and the average LF for each operation. As a result, the unified LF of the cultivator was 0.65, which was different from that of CAPSS (diesel, 0.48) and EEA (gasoline, 0.40). As a result of calculating the annual emission of the cultivator through the unified LF derived from this study and emission factors of EEA, emissions for CO and VOC were found to be higher in the cultivator than in the tractor and combine harvesters currently being statistically collected in South Korea. The results of this study are expected to provide useful information for estimating the LF and emissions of small agricultural machines equipped with gasoline engines, such as cultivators.