طراحي، ساخت ، ارزيابي و شبيه سازي سامانه مرتب ساز قلعه ها در يك قلمه كار نيشكر

چكيده انگليسي :

Design Development Evaluation and Modeling of a Billet Arranging System in a Sugarcane Billet Planter Earaj Bagvand ebagvand @gmail com March 14 2009 Department of Agricultural Machinery Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisors Sayed Jalil Razavi jrazavi@cc iut ac ir and Abbas Hemmat ahemmat@cc iut ac irAbstract Because of the nature of flowing billets in a metering device in current billet planters excessive billetconsumption low precision and control in placing the billets on the furrow is caused and use of billets with differentlength becomes limited To modify current billet metering device used on that planters Khani 2007 based on apatent by Pupolin and Pupolin 1976 developed a prototype of a billet metering device capable of one by one billetpicking and evaluated it on a laboratory test rig His results showed an undesirable effect of unarranged billets fed tothe secondary holding tank which attached to the one by one billet metering system This research was conducted to devise a system for continuous transfer and longitude arrangement of billetscoming from a main holding hopper and delivery to the secondary holding tank A prototype of the system wasdesigned and developed and the effect of some factors such as billet feeding rate 1 5 2 2 and 3 0 billet second angle of the chassis of the system 60 65 and 70 and position of outlet of the system relative to the secondaryholding tank walls near the center wall center and near the side wall on some parameters such as standing verticaland oblique billets were evaluated in laboratory and total error parameter was calculated In order to save time andmoney for modifications of the prototype a discrete element model of the system was developed using VisualNastran software Two important physical properties of billets i e coefficient of dynamic friction k andcoefficient of restitution e which required by the software were measured by developing tow special devices Calculation of motion acceleration of a body on an inclined surface was the base of k measuring device Thereforethree pairs of infrared emitter receiver for body motion detection and an electronic processor for processing signalssent by three receivers were developed and used in the device The base of e measuring device was to measure theimpact and rebound velocities of a wooden pendulum end impacting on a concrete anvil Then s coefficient ofstatic friction k and e of billets were measured In addition to obtain a criterion for validating the developedmodel developed system was evaluated in another experimental plan During this evaluation density center ofmass and number of nods of 180 billets with length of about 0 5m were measured Finally a model of the systemwas developed and its results compared with results of the pervious evaluation of the system Then this model wasused in modification of the prototype The results of system evaluation showed that total error significantly had maximum value in billet feeding rate of2 2 billet second and minimum value in near the side wall position for the outlet In addition tests showed anundesirable effect on the system s performance by short billets fed to the arranging system In general the systemperformance was very good so that up to 90 of the billets were arranged longitudinally and parallel to each other Calculated densities from measured mass and dimensions of billets showed that density of a billet increased withincrement in the number of it s nods From k measuring experiments a linear equation for k with sliding velocityon steel surface and from e measurements average values for billet billet and billet steel were obtained and used inmodeling Results of modeling matched with that of experiments and change of position of the system outlet in themodel according to experiment results improved arrangement of billets Keywords Sugarcane billet planter Billet arranging Discrete element Coefficient of dynamicfriction measuring Coe

بگوند، ايرج

طراحي، ساخت ، ارزيابي و شبيه سازي سامانه مرتب ساز قلعه ها در يك قلمه كار نيشكر

شبيه سازي المان گسسته , ويژوال نسترن , اندازه گيري ضريب جهش , اندازه گيري ضريب اصطحكاك جنبشي