Dr. R. YadavVegad Gautamray M.2017-07-012017-07-012012-07http://krishikosh.egranth.ac.in/handle/1/5810023958The goal of modern farming system is to economize energy consumption and to reduce farming cost. Optimal design of agricultural machines proportionate to the present tractor power must be considered in order to achieve this goal. This leads to an increase in farm efficiency, time saving in the farm operation, and maximizing the use of tractor power. Nowadays no efficient method has been developed to determine the optimal characteristics of rotary tiller’s tillage components. Proper selection and use of agricultural machines are important factors to achieve this end. Rotary tillers are the tillage tools that are used for accomplishment of both the primary and secondary tillage operations. Considering the widespread application of rotary tillers and modern tractors, optimal design of these machines is necessary. For designing the matching size rotavator, a computer program was prepared in Visual Basic 6 environment. The input parameters required for running the software were: power source, type of soil, allowable stress materials to be used for shaft and blades, speed ratio, forward speed of travel, number of blades working in the same plane, size of L type blade and rotor radius. The output parameters were overall width of machine, total number of blades, diameter of the shaft and angular interval between the blades. The various dimensions simulated by this software for matching size rotavator were compared with some of the commercially available rotavators having power requirement in the range of 12, 45 and 105 hp. The developed software could predict the basic dimensions of a rotavator within a variation range of 5 per cent limit. Technologies and computer capacity currently available allow us to employ design software and numerical methods to solve complicated problems in very wide disciplines of engineering. It is also important for researchers engaged in field of agriculture. In this study finite element analysis of three types of rotavator blades (i.e. C type, hatchet type and L type) were carried out using Solidworks and ANSYS software. 3D models of different blades were made using Solidworks software and static structural analysis of these blades were carried out using ANSYS software. The material and dimensions of C type and hatchet type blade were selected as per Indian Standard IS: 6690-1981, Specification for blades for rotavator. The dimensions of L shape blade were taken from the local manufacturing database of rotavator production system. Results of simulation showed that maximum deformation was observed as 1.98, 4.14 and 2.34 mm for C type, hatchet type and L type blade respectively at the given boundary conditions while maximum equivalent (von-mises) stresses of 340.23, 654.25 and 390.80 MPa were observed for C type, hatchet type and L type blade respectively. Maximum principal stresses were found as 309.07, 656.26 and 565.86 MPa for C type, hatchet type and L type blade respectively, whereas maximum shear stresses were observed as 194.07, 327.60 and 210.63 MPa for C type, hatchet type and L type blade respectively. Results obtained through simulation of three types of rotavator blades indicated that maximum deformation, maximum equivalent stress, maximum principal stress and maximum shear stress occurred in hatchet type blade and minimum deformation and different stresses occurred in C type blade. Hence hatchet type blade is more susceptible to failure against C type blade under loading conditions. The Solidworks designxpress module was utilized for the optimization study of three types of rotavator blades. In the optimized design of C type blade, the maximum equivalent stress was reduced from 340.23 to 299.35 MPa, total deformation reduced from 1.97 to 1.81 mm and mass decreased from 0.5043 to 0.4863 kg. After optimization of hatchet type blade maximum equivalent stress was reduced from 654.25 to 591.37 MPa, where as total deformation decreased from 4.14 to 4.09 mm and mass reduced from 0.6295 to 0.6132 kg. In case of L type blade after optimization maximum equivalent stress was decreased from 390.8 to 337.2 MPa, while total deformation reduced from 2.34 to 2.28 mm and mass reduced from 1.048 to 1.039 kg. The scientific literature signifies that agricultural machine of 1 kg has an equivalent energy of 62.7 MJ. The simulation applications, which are based on 3D modeling, numeric methods and optimization methods are therefore becoming more common in the product design area, not only for saving design time, but also to reduce manufacturing costs as well as reduction in energy consumption. Consequently, the usage of these applications in the agricultural machinery design and manufacturing process will provide important benefits to create optimum designs of the agricultural machineries and to reduce the cost.enengineering & TechnologyThesis