Effect of air-jet impingement parameters on the removing of sunflower seeds from the heads in static conditions

Abstract

Due to the success of air-jet in food and agricultural sciences, in order to eliminate a number of problems in mechanical methods of removing sunflower seeds from the head, a new method was invented based on impingement jets.  In fact, the aim of presenting the air-jet impingement method was not to design this simple machine.  But when we started designing the final machine, we realized that we need to take a step back and study the jet parameters in simple and static state.  The effect of the seeds’ location on sunflower head, reservoir pressure, the angle of impingement, nozzle diameter and the distance between the nozzle outlet and the surface of the sunflower head on the removed area of sunflower head in static conditions were examined.  The regions removed by the impingement of the air-jet were photographed and the area of the removed regions was calculated. Response surface methodology was used for designing experiments for all three regions of sunflower head of “Dorsefid” variety.  Based on the obtained results of two varieties, on side, middle and central regions, removing seeds using 30°, 60° and 90° angle of impingement is advised respectively.  The results indicated that the area of the removed regions was increased with the increase of the nozzle diameter and reservoir pressure. Also the removed area increased with the increase of the distance between the nozzle outlet and the surface of the SH at first, but then decreased. The optimal distance between the nozzle outlet and the surface of the SH ranges between 24 to 28 mm.