The Effects Of Mat Depth And Cutter-Head Knives On The Cutter-Head Energy Of A Forage Harvester Using Pueraria phaseoloides As A Forage Material

Abstract

Samples of Pueraria phaseoloides were collected from Oban Division of Cross River State National Park, Nigeria between April to September 1995. The samples were chopped with a 45cm diameter cutter-head fitted with 6, 9, 12 and knives. Forage at 65 percent moisture content (wet basis) was fed on the conveyor at a linear velocity of 0.57m/s. The theoretical length of cut was set at 6.4mm and the shear bar clearance adjusted to 0.3mm. The feeding mechanism was adjusted for different mat depths, 5.1cm, 7.6cm and 10.2cm. The torques applied and the actual speed of the cutter-head was recorded. The cutter-head energy (kwh/t) was calculated from the average torgue applied to the cutter-head and the average angular velocity of the cutter-head. The result showed that the cutter-head decreased significantly with the increase in the number of knives on the cutter-head. At the 5.1, 7.6 and 10.2cm mat depths increasing the number of knives from 6 to 36 reduced the cutter-head energy by 0.29kw/t (75%), 0.489kw/t (80%) and 0.645 Kwh/t (83%) respectively. The cutter-head energy was found to have increased with increase in mat depth. The average increase in cutter-head energy when the mat depth was increased from 5.1-7.6cm and 5.1-10.2cm were 98.8% and 134.4°C respectively. It was also observed that with 36 knives, the effect of the increase in mat depth was minimal. The differences in cutter-head energy from 5.1-7.6cm and 5.1-10.2cm mat depths were significant (P<0.05) showing that increase in mat depth would increase the cutter-head energy.

Journal of Applied Chemistry and Agricultural Research Vol. 5 1998: pp. 75-78