Modelling of Gyroscopic Motion Approach to Peeling of Cassava Tubers on the Basis of Energy Consumption.

Abstract

Introduction: This paper is on modelling of the abrasive peeling of cassava tubers with some form of gyroscopic motion into the operation. The machine action required three motions of rotation, rocking and revolution of the abrasive peeling drum and balls. As such two or three electric motors are needed to provide the required motions, hence energy consumption was a major concern

Objectives: the objective is to develop a predictive model of the energy consumption rate of the peeling machine which can be used as a basis for design.

Methods:  the involves developing A predictive mathematical modelling of the energy consumption rate during peeling was carried out, which revealed the angular velocity of the shaft, drum and the abrasive balls (ω_d), unevenness of the product surface (Φ), abrasive teeth shape and protrusion ( λ) and angular velocity of the revolving assembly (ω_g) as the basic factors affecting peeling rate

Results:  The results show that the motion of cassava in the chamber remains random for the different speeds of rotation modelled in this research. The limit set for each rotation was 100mm in diameter, and they are modelled for two cycles of 360⁰ or 2π radians. In all the different speeds of rotation from 20rpm to 160rpm in steps of 20rpm, no appreciable difference in the motion was observed. Energy consumed during cutting shows remarkable difference with 20rpm recording the highest value of 6.0 x 10⁸J and 120rpm producing the minimum value of 1.0 x 10⁸J. It was also observed that, at 80rpm,100rpm, 140rpm and 160rpm the energy consumption rate is the same at 1.5 x 10⁸J.

Conclusions: The predicted values shows that the energy consumption rate of the machine is quite reasonable for the commercialization of the machine.