Energy performance of an agricultural articulated tractor: Manual and automatic modes

ABSTRACT Automatic production management (APM) is a tool that assists in the operations of agricultural tractors, increasing yield and energy efficiency. The objective of the experiment was to compare the energy and operational performance of a 373-kW articulated tractor equipped with APM and manual mode of engine transmission and rotation, across different real-world speeds. The experiment was conducted in a randomized block design with five replicates, using a split-plot arrangement with two system modes (manual and automatic) in the plots and four real-world speeds (4, 6, 8, and 10 km h-1) in the subplots, totaling 40 experimental units. The evaluated variables were: wheel slippage; engine rotation; hourly and specific fuel consumptions; drawbar force, power, and yield; operating speed; and engine thermal efficiency. The variance of the data was analyzed using Tukey’s test for the first factor, and regression analysis for the second factor and interactions. The automatic mode showed lower engine rotation and wheel slippage without compromising the other variables. The use of this mode showed energy advantages at 4 and 6 km h-1 by resulting in less fuel consumption per hour. In addition, the manual mode presented higher thermal efficiency at lower speeds than the automatic mode, which showed a linear increase.

摘要：自动生产管理系统（Automatic Production Management）是一款辅助农用拖拉机开展作业的工具，可提升作业产量与能源利用效率。本试验旨在对比搭载APM的373千瓦铰接式拖拉机，在4种实际作业车速（4、6、8、10 km·h⁻¹）下，分别采用发动机传动与转速手动模式及自动模式时的能源与作业性能。试验采用随机区组设计，设置5次重复，采用裂区布置：主区设置2种系统模式（手动、自动），副区设置4种实际作业车速，总计40个试验单元。本试验评估的变量包括：车轮滑转率、发动机转速、小时燃油消耗量与比燃油消耗量、牵引杆牵引力、牵引功率、作业产量、作业车速及发动机热效率。数据方差分析中，针对主效应因素采用Tukey检验，针对次级效应因素与交互效应采用回归分析。结果表明，自动模式可降低发动机转速与车轮滑转率，且未对其余变量造成不利影响。在4与6 km·h⁻¹的作业车速下，采用自动模式可展现能源优势，表现为小时燃油消耗量更低。此外，在较低作业车速下，手动模式的发动机热效率高于自动模式，而自动模式的热效率呈线性增长趋势。