Optimization of Fuel Consumption for Tractor-tilled Land Area During Harrowing Operation Using Full Factorial Experimental Design

This study's aim is to improve the tractor harrowing operation's fuel consumption efficiency to cut operating costs and boost agricultural output. The field trial was conducted at Rivers Institute of Agricultural Research and Training (RIART) Farm, Rivers State University, Port Harcourt. The 4,480 m2 experimental land area, which measured 160 by 38 meters, was divided into three blocks of nine plots each. For the alternative treatment choices, each plot was laid out at 50 m by 2 m, with a path dimension of 1 m between each plot and 2 m between each block and 1 m at the sides of the outer blocks. The tilled area fuel consumption and the field test parameters (harrowing depth and tractor forward speed) were measured in accordance with their respective requirements. Statistical studies of the general full factorial design (GFFD), including model fit assessment, analysis of variance (ANOVA), main and interaction effects, multiple linear regression model, and response optimizer, were carried out using MINITAB 19 software. Standard error (SE), coefficient of determination (r2), adjusted r2, and prediction r2 were also used to test the model's validity. The influence of harrowing depth, tractor forward speed, and their interactions are statistically significant on the tilled area fuel consumption during harrowing, according to the Pareto charts of standard effect. The tilled area fuel consumption data during harrowing were nearly normally distributed, as shown by the normal probability plots, which satisfies the first requirement of the model fitness analysis. A roughly normal distribution was also visible on the histogram plot. This observation also provides more evidence in favor of the typical fuel usage distribution in tractor-tilled areas. The residual vs. fitted value graphs showed that there is no discernible pattern in the data points for tilled area fuel consumption data during harrowing, supporting the constant variance condition of the residuals. A plot of the residual versus observation order reveals that the residual points are likewise entirely random. According to the statistical study, the effects of harrowing depths, tractor forward speed, and their interactions on tractor tilled area fuel consumption during harrowing operation were significant with 95 and very significant with 99% confidence (P<0.05 and P<0.01 levels of significance). Also, it was demonstrated for example that the multiple linear regression could accurately predict the experimental results with a standard error of very small amounts. For the amount of fuel consumed during harrowing in the tilled area, the coefficients of determination (r2), adjusted r2, and anticipated r2 were all equal to 100%. indicating that the estimated multiple linear regression model created for the tractor tilled area fuel consumptions explained 100% of the variability in the dataset. At harrowing depth of 0.09 m and tractor forward speed of 5 Km/h, optimal tractor tilled area fuel consumption during harrowing was achieved. According to this study, the required minimum fuel consumption for tractor-tilled area under operational parameters (harrowing depth and tractor forward speed) was 6.15 L/ha