Modelling of the effects of working width, tillage depth and operational speed on draft and power requirements of disc plough in sandy-clay soil in South-East Nigeria

Abstract

Discrepancies amongst ecological soil situations necessitate records of the performance of machines under diverse soil categories for choice of tools to lessen cost, minimize energy loss, and increase agricultural production. This research sought to investigate to what extent the working width, operational speed and cutting depth influence the draft force and power requirements of disc plough in sandy-clay soil in South-East Nigeria, and to obtain model equations that could predict the draft and power necessities of the implement, which would be a guide to selecting apposite ploughing implements based on soil type/conditions in South-East Nigeria and other areas globally with similar soil type/condition.. Results specified that the highest draft force of 3.051 kN/m was obtained when the plough was operated at working width of 60 cm, depth of 20 cm and speed of 7 km/hr. While the highest drawbar power of 5.42 kW was achieved when the plough was engaged at full width of 180 cm, tillage depth of 15 cm and speed of 6 km/hr. Statistical analyses showed that tillage depth and operational speed has significant effect (p˂ 0.05) on the draft force and drawbar power of the disc plough as compared to the working width. Quadratic model was statistically significant for the responses (P ˂ 0.05). Results pointed out that the coefficient of determination; R2 was 0.9993 for draft force and 0.9759 for drawbar power, which indicated high correlations amidst the factors. The Predicted R² of 0.9888 for draft force was reliable with the Adjusted R² of 0.9984. While the Predicted R² of 0.6140 for drawbar power was reliable with the Adjusted R² of 0.9449. The adequacy Precision (100.383 for draft force and 19.912 for the drawbar power) obtained indicated decorous indicator and that the models could navigate the design space. The optimum draft force and drawbar power of 1.95 kN/m and 4.95 kW were respectively achieved with the desirability of 1.000 at optimal working width of 119.06 cm, ploughing depth of 13.71 cm and operational speed of 7.74kmh−1. Farmers can hereafter, appraise and select the disc plough with the models.