振动气吸式穴盘播种机的吸种性能研究

为了促进精量播种机的开发与应用,该文对振动气吸式穴盘播种机的吸种性能进行了理论分析。在种子盘近似单频被激振动的情况下,忽略种子空气阻力,使被抛掷的种子“沸腾”起来,以减少种子间的内摩擦力,提高吸种,固种能力。此时把空气流看作等熵流动,从而得出数学模型。试验结果与数学模型基本吻合。结果表明：在一定的真空度下,随着吸嘴直径的增大,吸种能力也随之上升,但吸嘴直径一定要小于种子的直径。吸种质量随吸嘴真空度的增加而提高,真空度较小时,对吸种高度的影响比较明显,真空度较大时,影响较小。真空度有一极限值48 kPa,在此真空度以上不能改善吸种质量;而在一定的真空度下,吸种高度随吸嘴直径变化比较明显均匀。

Seed suction performance of vibrational air-suction tray seeder

The theory of seed suction performance of vibrational air-suction tray seeder was analyzed in order to promote the exploitations and applications of precision seeders. When seeder tray was approximately vibrated with single frequency and the air resistance was ignored, the seeders tossed were "boiling" to reduce the inner friction force, which increased the capacity for sucking and fixing seeds. The air flux was then thought equal entropy flux, therefore the mathematical model was obtained. The result of experiments is basically in accord-ance with the mathematical model. At certain vacuum, the capacity for sucking seeds is raised with the increase of sucking mouth diameter, but the sucking mouth diameter must be less than the seed diameter. The quality of sucking seeds is improved with the increase of vacuum in the sucking mouth. With comparatively smaller vacuum, the effect of vacuum on the height of sucking seeds is conspicuous and the effect becomes less with the bigger vacuum. The vacuum has a limit value of 48 kPa, above which the quality of sucking seeds cannot be increased. The height change of sucking seeds tends to be distinct and uniformity with the increase of sucking mouth diameter at certain vacuum.