A CENTRAL-TYPE JET PUMP MODEL FOR WHEAT GRAINS REMOVING FROM WATER CHANNELS

The aims of this research were (i) to design a central-type jet pump model to remove wheat grains from water channels and (ii) to establish a test-rig for jet pump model performance test. Experiments were performed using wheat grains and water. The experiments deals with the performance and choice of suitable nozzle distance ratio and area ratio (area of motive flow nozzle to area of mixing chamber) for a central-type jet pump model with the following parameter: 7.25 mixing chamber length ratio (length of mixing chamber to mixing chamber diameter), diffuser angle of 5.5 o and wheat concentration ratio from 5% to 35%. The experimental rig was constructed such a way it can be changing the driving nozzle diameter and the distance between the nozzles to throat. In this study three different diameters of driving nozzles, namely (10, 12.7 and 16 mm) have been used with one mixing chamber of 25.4 mm diameter (i.e. three different area ratios of R= 0.155, 0.25 and 0.4). The effect of nozzle to throat spacing to nozzle diameter ratio "X" with values of 1, 1.5 and 2, on the jet pump performance was also tested under different flow rates and motive pressures. From the experimental work, the beast and suitable nozzle distance ratio and area ratio are obtained. The effect of wheat concentration on jet pump efficiency was also measured. The research proved the ability to use a centraltype jet pump model successfully for the first time for wheat grains removing from water channels up to 35%. The results allow prediction of how a similar practical unit behaves in order to remove the wheat grains from the bottom of water channels.