Traction - energy estimation of the tractor in the composition of agricultural unit of variable weight

Abstract

The methodological foundations for assessing the traction and energy indicators of tractors driven from the power take-off shaft of the active working bodies of agricultural machines of variable weight are substantiated. The instability of the specific fuel consumption of the tractor engine with a change in the power transmitted through the power take-off shaft has been proved. For tractors of the traction and energy concept, the solution to the problem of energy saving is relevant, especially for transport and technological units of variable mass. The paper proposes to assess the traction and energy properties of a tractor unit driven from the power take-off shaft of the active working bodies of agricultural machines according to its structural diagram. Using the example of an agricultural unit as part of a Belarus 3022 DC.1 tractor (Ukrainian assembly) when aggregated with a PMF-18 solid organic fertilizer spreader, it has been proven that a decrease in the weight of the load in the bunker from full to empty leads to a decrease in the engine load factor from 0.92 to 0.6. When operating a tractor with agricultural machines with a variable weight during operation, or reducing the weight of the load in the bunker, it is recommended to operate the engine in partial mode, which leads to fuel savings of up to 28%. For tractor units driven by a power take-off shaft of agricultural machines that have several active working elements, for example, a Fendt 920 Vario tractor with a Krone Big Pack 1290 XC baler, fluctuations in the power required to drive the power take-off shaft lead to a deviation of the specific fuel consumption from the optimal values by ± 10%