Influence of soil moisture on energy requirement of rotary tilling

Abstract

The rotary tiller with ‘L’ shaped blades was examined for torque, power and specific tilling energy requirements to attain optimum soil-machine operational parameters. The three levels of moisture content (11.4%, 12.8% and 14.6% (d.b)), three speed ratios of 20 (?1), 12 (?2) and 9 (?3) at different passes (first, second and third) with rotational speed of 262 rpm were selected for study. The observations indicated inverse relation between torque and power requirement to moisture content. The lowest value of torque of 16.54 N-m and 26.66 N-m was associated with sandy loam and clay loam soil under third pass and moisture content of 14.6 per cent. Similarly, the minimum power requirement of 0.452 kW and 0.699 kW was observed under analogous conditions of rotary tiller. The energy requirement was found to decrease with higher number of passes due to the breakdown of the hard pan and clod aggregate size.  The specific tilling energy is strongly correlated with forward speed and less dependent on the number of the passes of rotary tilling.