Design Optimization of Rotary Tiller Blade using Specific Energy Requirement

International Journal of Agricultural and Biological Engineering, 2009

The goal of the modern farming systems is to economize energy consumption and to reduce farming costs. Proper selection and use of agricultural machines are important factors to achieve this end. Rotary tillers are tillage tools that are used for accomplishment of both the primary and secondary tillage practices. Considering the widespread application of rotary tillers and wide use of modern tractors in Iran, optimal design of these machines is mandatory. Therefore in this study, the optimal working width and optimal diameter of the rotary tiller's rotor proportionate with the power of the MF 399 tractor was delineated based on the energy method. This theoretical method is based on the specific works of tractor and rotary tiller. Results showed that the optimal working width and optimal diameter of the rotary tiller' s rotor with maximum of forward speed 1 m/s for tractor was 240 cm and 6.27 cm, respectively.

Tillage is an operation performed to obtain a desirable soil structure for a seedbed or root bed. A granular structure is desirable to allow rapid infiltration and good retention of rainfall and to minimize resistance to root penetration. Rotavator (also called rotary tiller) is a tractor operated cultivating implement that breaks or works the soil with the help of rotating blades. The use of rotavator is increasing due to its versatility in doing a good quality tillage job with minimum number of passes. The rotavator do simultaneous ploughing and harrowing in dry and optimum soil moisture in single operation. The blades are the main critical parts of a rotary tiller which are engaged with soil. So, wearing takes places at the cutting edges of these blades due to high stresses are coming. In this context a lot of research on rotavator blade has been carried out in different parts of the world. This paper briefly reviews the work done so far on the rotary tillers' blade design optimization and development.

Journal of Manufacturing Engineering, 2022

A rotary tiller or rotavator is active tillage equipment used to prepare farmland for sowing seeds, weeding, mixing manure and fertiliser into the soil, crushing soil blocks, etc. Compared with conventional farming, the advantages of this equipment are rapid seedbed preparation and reduced draught. Nowadays, the utilisation rate of rotary tillers has increased. However, the blades are the key component that engages with the soil in the rotary tiller. These blades interact with the soil differently from ordinary ploughs and bear impact loads and high frictional forces, which eventually generate unbalanced and uneven forces on the entire rotary tiller. As a result, the blade faces significant wear. Therefore, it is necessary to optimise the design of the blades to minimise wear and enhance the service life. In this research work, design optimisation was carried out towards improving service life.

Tillage is an operation performed to obtain a desirable soil structure for a seedbed. A granular structure is desirable to allow rapid infiltration and good retention of rainfall, to provide adequate air capacity and exchange within the soil and to minimize resistance to root penetration. Rotary tiller or rotavator (derived from rotary cultivator) is a tillage machine designed for preparing land by breaking the soil with the help of rotating blades suitable for sowing seeds (without overturning of the soil). Nowadays, utilization of rotary tillers has been increased in agricultural applications because of simple structure and high efficiency. However in a rotary tiller, blades are the main critical parts which engaged with soil to prepare the land. These blades interact with soil in a different way than normal plows that are subjected to impact load and high friction which ultimately creates unbalancing and non-uniform forces on the rotary tiller. This result wears in the blades. Therefore, it is necessary to optimize the design of blade so that wear will minimum and thereby enhanced the service life. The present research has dealt with design of “L” type blade for tractor drawn Rotary tiller or Rotavator using Specific Work Method (SWM).

Biosystems Engineering

Strip-tillage research in developing countries usually relies on commonly used rotary blades designed for conventional full disturbance soil tillage. With the aim of optimising the blade geometry and operational settings, this study investigated the effect of three blade geometries (conventional, half-width and straight) at four rotary speeds (125, 250, 375, and 500 rpm) on torque, power and energy characteristics. A single row rotary tiller was fitted with the blades set at a cutting width of 50 mm and depth of 50 mm and tested in a soil bin (sandy loam soil). Analyses of high speed video images and corresponding blade motion revealed that the peak torque occurred at a higher blade penetration depth as the speed increased indicating transformation of the peak torque requirement from due to initial soil failure at a low speed to final soil cutting and throwing at a high speed. The straight blade design required the least torque, average power, peak power, specific energy and effecti...

Environment Conservation Journal, 2021

The rotary tiller with ‘L’ shaped blades was examined for torque, power and specific tilling energy requirements to attain optimum soil-machine operational parameters. The three levels of moisture content (11.4%, 12.8% and 14.6% (d.b)), three speed ratios of 20 (?1), 12 (?2) and 9 (?3) at different passes (first, second and third) with rotational speed of 262 rpm were selected for study. The observations indicated inverse relation between torque and power requirement to moisture content. The lowest value of torque of 16.54 N-m and 26.66 N-m was associated with sandy loam and clay loam soil under third pass and moisture content of 14.6 per cent. Similarly, the minimum power requirement of 0.452 kW and 0.699 kW was observed under analogous conditions of rotary tiller. The energy requirement was found to decrease with higher number of passes due to the breakdown of the hard pan and clod aggregate size. The specific tilling energy is strongly correlated with forward speed and less depe...

2015

The continuous increase in fossil fuels price has resulted substantial and tremendous increase in the cost of land preparation. This has direct effect on the food pricing which in turns results in considerable increase in the cost. The situation is worsened by the prevalent use of the conventional tillage system in the preparation of seedbeds, particularly for deep tillage. This system of tillage escalates land preparation costs because it requires a series of operations using passive tillage tools to realize an acceptable tilth quality. It also ties down capital in the form of additional machinery and tillage tools; thus increasing significantly the cost of land preparation. Rotary tiller is a most suitable tillage machine designed for seedbed preparation. Blades are the main critical parts of a rotary tiller, which are engaged with soil to prepare the land. These blades interact with soil in a different way than normal plows which are subjected to impact and high friction which ul...

Current Journal of Applied Science and Technology

Several advantages of rotavator including negative draft generation make it the most suitable attachment to power tiller. Many factors affect the economy and performance of power tiller which includes specific energy consumption, resourceful use of available power, produced soil conditions and blade durability. Hence a systematic design method was developed for power tiller rotavator while considering all these factors simultaneously. Specific work done by rotavator was equalized with performable work of power tiller for different combination of design and kinematics parameter. The value of design and kinematic parameters included in the previous step were limited by the extremities. These limitations were imposed so as to get desired soil conditions and blade durability. The best combination of parameters that produces the desired soil condition with minimum specific energy consumption while utilizing the available power resourcefully was selected. Other design parameters were calc...

AFRICAN JOURNAL OF AGRICULTURAL RESEEARCH, 2011

The aim of this paper was to analyze the influence of rotary tiller rotor rotation direction on specific work requirement (SW PTO ). The SW PTO was calculated by measuring the power take-off (PTO) torque, PTO speed, working speed and depth, as well as the working width. The tillage quality was determined by the bulk density and soil structure. Reverse rotor rotation direction concept is characterized by more efficient tillage which provides significantly higher amount of macro-structure aggregates (0.25 to 10 mm) and their better distribution in the soil. Significantly lower SW PTO was observed with the reverse rotor rotation direction. It was within the range of -2.15-27.74% (14.35% on average) depending on the work speed which was 0.29 to 1.08 m s -1 . Multiple linear regression provided new equations for the calculation of SW PTO depending not only on the working parameters, but on the intensity of soil breaking and soil conditions as well. The obtained equations had high values of Coefficients of determination R 2 (0.92 to 0.99 for conventional and 0.84 to 0.93 for reverse rotor rotation direction). Reverse rotor rotation direction had lower SW PTO values which were 20.3 and 15.5% for the working speeds of 0.5 and 1.0 m s -1 , respectively, and were obtained for equal values of tillage intensity parameters.

Journal of terramechanics, 1993