Development of an empirical model based on the dimensional analysis for predicting the fuel consumption of two Tractors: DEUTZ FAHR Agrotrac and Torpedo TD 68

Abstract

This study aims to develop empirical models for predicting the hourly fuel consumption of two agricultural tractors, namely the Torpedo TD68 and the DEUTZ FAHR Agrotrac, using dimensional analysis as a modelling tool. The experiments were conducted in two contrasting agroecological regions: the ENSA experimental station in Algiers, located in the Mitidja plain, and the ITGC station in Sétif, representative of the semi-arid High Plateaus. The measurements focused on the physico-mechanical properties of the soil, including soil moisture, bulk density, porosity and penetration resistance, as well as tractor operating parameters such as forward speed, engine speed, working depth, wheel slip and fuel consumption. The results obtained in Algiers showed that tillage operations improved the structural condition of the worked soil layer by reducing penetration resistance, particularly after the use of the vibrocultivator and the cover-crop. However, plowing with the Torpedo TD68 revealed a major limitation in traction performance, with a very high wheel slip of 54.40%, indicating significant energy loss through skidding and low efficiency in power transmission to the soil. In Sétif, deep tillage at 50 cm using the DEUTZ FAHR Agrotrac resulted in a significant reduction in penetration resistance, indicating good fracturing of compacted soil horizons. However, this operation required a high energy demand, with fuel consumption increasing from 6.15 L/h under no-load conditions to 54.9 L/h under load. Despite this, wheel slip remained at 13.80%, which corresponds to an optimal traction range. The comparison of the two models shows that penetration resistance is the most determining factor in fuel consumption, especially in Sétif, while wheel slip has a greater influence on fuel consumption in Algiers. These models represent useful tools for optimizing tractor– implement selection, reducing energy losses and improving the efficiency of agricultural mechanization.