5294

4968

كارشناسي ارشد

مكانيك ماشين هاي كشاورزي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1388

چهارده،124ص.:مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

سيد جليل رضوي

عباس همت،سيروس فرهمند

6/4/89

امين ا... معصومي،منوچهر حيدرپور

مهندسي كشاورزي

ID4968

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Abstract Rice is an important food staple and it is considered a strategic crop after wheat in Iran Any effort to decrease its loss during harvest time would contribute to self sufficiency in its production Grain losses at harvest time and specifically rice crop losses constitute highest level of losses during production process Combine harvesting losses of rice crop in Iran are 2 to 3 times higher than standard levels elsewhere Combine platform losses constitute more than 50 percent of total losses therefore any reduction in this section of the combine is an important step towards increasing harvest efficiency In this research design of a hydraulic system to power platform reel on a rice combine model GUSHENZHIFU was considered in line with efforts to study effect of forward speed and feeding rate on platform grain losses percentage In the first step current level of reel losses was evaluated working with its current power train system of pulley and belt Then a hydraulic system was designed based on power and torque requirement of the reel The system included an external gear pump internal gear hydro motor gyrator 3 way flow control valve one step hand operated pressure control valve and DC electrical directional spool type valve System simulation was performed using Automation Studio software and after this stage installed on the platform of the combine The hydraulic system provided a 10 50 RPM reel speed range with the capability of change in its rotational speed as forward speed changes an important capability not available not present with mechanical power trains Power and torque consumption of the reel was measured for various working conditions At no load power and torque requirements were 0 072 KW and 15 N m respectively Effects of hydraulic power train combine forward speed and height of cut on platform losses were determined with a completely randomized design with three replications A significant difference in platform losses was observed between the hydraulic and mechanical power trains With hydraulic mechanism lowest rate of losses was obtained at 1 75 Km hr 1 forward speed and 1 4 height level from ground surface An increase in forward speed from 1 75 km hr 1 to 3 25 Km hr 1 and height of cut from 1 4 to 3 4 crop height resulted in significant increase in platform losses Rate of feeding crop material which depends on height of cut and combine forward speed was calculated and its relation to platform losses was determined It was observed that with increase in rate of feeding crop material platform losses increased in both hydraulic driven and mechanical driven power trains Keyword Rice combine harvester Platform Driven power of hydraulic

سيد جليل رضوي

عباس همت،سيروس فرهمند

امين ا... معصومي،منوچهر حيدرپور