3227

3154

كارشناسي ارشد

﴿مكانيك ماشين هاي كشاورزي ﴾

اصفهان : دانشگاه صنعتي اصفهان ، دانشكده كشاورزي

1384

دوازده ، 54 ، [II] ، ص : مصور ، جدول ، نمودار

ص . ع : به فارسي و انگليسي

امين الله معصومي ، عباس همت

عبدالمجيد رضايي

مرتضي صادقي ، سيد محمود ميبدي

مهندسي كشاورزي

ID3154

به فارسي و انگليسي : قابل رويت در نسخه ديجيتالي

Abstract One of the methods for increasing yield per hectare is to change the row width from60 cm to 50 cm For using medium power tractors JD 3140 available in Iran forpulling a three row sugarbeet lifter in 50 cm row width crop vibrating the shanks ofthe sugarbeet lifter was recommended Effects of vibration frequency and approachangle of a vibratory sugarbeet lifter on its performance during harvesting werestudied Draft resistance slippage percent of broken and non harvested tubers weredetermined for four vibration frequencies 0 9 10 and 12 Hz and three approachangles 11 24 and 36 deg using a factorial treatment arrangement in a completerandomized block design with three replications The results of analysis of varianceindicated that all measured parameters were significantly affected by the frequency ofvibration and the approach angle of the lifting shares P 0 01 The results showedthat variations in draft and slip were similar with frequency and approach angles Themaximum draft value was at 36 deg of approach angle and zero frequency non vibrated shanks with 12 1 kN while corresponding minimum value was at 24 deg ofapproach angle and zero frequency with 7 7 kN Optimum slip values 10 15 percent were obtained at approach angles and frequencies of 11 deg and 12 Hz 24 deg and10 Hz and 36 deg and 12 Hz respectively Minimum percentages of broken and non harvested tubers were obtained at approach angle of 24 deg and frequency of 9 Hz 1 4 and 5 1 percent respectively The results indicated that percent of non harvestedtubers decreased with an increase in approach angle However percent of brokentubers decreased and increased with an increase in approach angle and vibrationfrequency respectively A ratio K of draft resistance and percent of harvested beets undefected and broken tubers was definded for selection the optimum combinationof approach angle and vibration frequency The analysis of variance showed that Kratio was significantly affected by frequency and approach angle and their interactions P 0 01 Based on K ratio optimum operating conditions for sugarbeet harvestingwith the vibratory lifter is at approach angle of 24 deg and vibration frequency of 10Hz

امين الله معصومي ، عباس همت

عبدالمجيد رضايي

مرتضي صادقي ، سيد محمود ميبدي