AERODYNAMIC ANALYSIS AND PERFORMANCE EVALUATION OF RICE MILLING MACHINE

Abstract

Experiments were carried out to derive aerodynamic analysis and evaluate the performance of a rice milling machine. Physical and engineering properties of grains under study have to be considered to study their effect on the performance of the milling machine. The performance of the milling machine was studied under the following parameters: feed rate, drum speed, concave clearance and seed moisture content. Performance evaluation of the machine was carried out in terms of overall machine efficiency, total grains losses, machine productivity, required power, specific energy and criterion cost. The experimental results reveal that the highest values of machine productivity and overall machine efficiency were 925 kg/h and 92.38%, while the lowest values of required power and specific energy were 9.2 kW and 11.95 kW.h/Mg, furthermore the lowest values of both operational and criterion costs were 9.15 L.E./ Mg and 48.05 L.E./ Mg, respectively. The optimum operating parameters of milling machine were found at 10 m/s air velocity by using 1.4 Mg/h feed rate with 10 mm concave clearance and 850 rpm drum speed at 16 % grain moisture content.