نوع مقاله : مقاله پژوهشی (کاربردی)
نویسنده
عضو هیات علمی،گروه مهندسی کشاورزی، دانشگاه فنی و حرفه ای تهران، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسنده [English]
This study was performed to design and evaluate an off-center hydraulic inertia harvesting machine. The physical properties of Shirazi sour apple tree were calculated based on natural frequency, damping constant, damping coefficient and branch stiffness. Next step was to evaluate the efficiency of machine for separating and harvesting of fruits at different frequencies, amplitudes and times, a factorial experiment (3 × 3 × 3) was performed in completely randomized design. Treatments were frequency at the levels of 20,25 and 30 Hz, amplitude at the levels 50, 60 and 70mm and vibration time at levels of 5, 10 and 15 seconds. The results of analysis of variance showed a significant effect (p <0.01) of treatments and their interaction. Increasing vibration frequency in tree, a significant effect was obtained but in the range above 60mm, the effect of increasing the frequency was significant. Therefore, in fruit harvest, the effect of increasing the amplitude of oscillation relative to the frequency on increasing fruit drop was concluded. The study of the relationship between the static force of separation and weight was fitted as a linear relationship. With increasing the vibration time from 5seconds to 10 seconds, harvest increased but with increasing the time from 10 to 15 seconds, no significant effect was achieved. Based on the results, the harvesting frequency of sour apple fruit equal to 25 Hz in the range of 70 mm and vibration duration of 10 seconds with an average drop of 88.4% was selected as the best treatment.
کلیدواژهها [English]
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