AbdolMajid Moinfar; Gholamhossein Shahgholi; Yousef Abbaspour-Gilandeh; Tarahom Mesri Gundoshmian
Abstract
The four-wheel drive and rear-wheel drive tractors are commonly used in agricultural operations. In order to investigate the effect of a type of driving system a series of tests were performed usin the three driving systems of foour wheel drive, rear wheel drive and front wheel drive in different axle ...
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The four-wheel drive and rear-wheel drive tractors are commonly used in agricultural operations. In order to investigate the effect of a type of driving system a series of tests were performed usin the three driving systems of foour wheel drive, rear wheel drive and front wheel drive in different axle loads of 0, 150 and 300 kg, tire inflation pressures of 170, 200 and 230 kPa and travel speeds of 1.26, 3.96 and 6.78 km/h. Bulk density was measured as an indicator of soil compaction at different depths of 10, 20, 30 and 40 cm. Also, under the different conditions, the drive wheel slip was measured. To carry out the tests, the four-wheel tractor of Goldoni 240 was used which has the ability to work with mentioned driving systems. The experiments were carried out under controlled conditions in a soil channel with the length of 3 m and a width and depth of 1 and 0.6 m, respectively. Test were conducted in completely randomised block design with three repetations and results were analysied using SPSS 22 software. The results showed that by changing the driving system from 4WD to RWD and FWD, there was a significant increase in soil density, with the lowest density associated with 4WD system and the highest density related to FWD. The reason for increasing the density by changing the driving system can be attributed to different slip levels in each of these systems due to the lower slip percentage of the 4WD system than the other two systems. Increasing axial load increased soil boulk density. Of note that with increasing the axial load, the stress was transferred from the surface soil to the subsoil layers. As the axial load on tire increases, the subsoil density was closer to the surface layer. Increased axial load on tire and decreasing tire pressure reduced wheel slip. Stepwise regression model with determination coefficient of 0.92 and according to calculated standard coefficients showed that axial load, soil depth, type of driving system, tractor speed, and finally tire pressure, have the greatest effect on soil bulk density, respectively.
Mohammad Askari; Gholamhosein Shahgholi; Yousef Abbaspour-Gilandeh
Abstract
In this research, horizontal, vertical and side forces on a single bentleg plow (SBLP) and a double bentleg plow (DBLP) at four forward speeds of 1.8, 2.3, 2.9 and 3.5 kmh-1 and at the constant depth of 40 cm was evaluated. The experiment was arranged in the randomized complete block design with four ...
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In this research, horizontal, vertical and side forces on a single bentleg plow (SBLP) and a double bentleg plow (DBLP) at four forward speeds of 1.8, 2.3, 2.9 and 3.5 kmh-1 and at the constant depth of 40 cm was evaluated. The experiment was arranged in the randomized complete block design with four replications. In each experiment, three perpendicular soil forces were measured and recorded. Results showed that increasing forward speed from 1.8 to 3.5 kmh-1 resulted in increasing horizontal, vertical and side forces by 14, 3.5 and 1% for SBLP and 13, 1.2 and 11.5% for DBLP, respectively. Other results indicated that horizontal force for DBLP was more than twice of that for SBLP. The vertical force was lower for SBLP but it was not more than half that of DBLP and the side force for DBLP was very less than that for SBLP. Generally, using the DBLP increases tine penetration and decreases side force which leads to balanced operation of the subsoiler and tractor and therefore recommended.
kamel قادرنژاد; Gholamhossein Shahgholi; Aref Mardani
Abstract
One way to reduce soil compaction is to add organic matter and to manage the field traffic. In this research, farmyard manure was incorporated into clay soil with rates of 0, 45, 60, 90 ton ha-1. After 6 months (September to March), at different numbers of tyre passes of 1, 6, 11 and 16, and three soil ...
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One way to reduce soil compaction is to add organic matter and to manage the field traffic. In this research, farmyard manure was incorporated into clay soil with rates of 0, 45, 60, 90 ton ha-1. After 6 months (September to March), at different numbers of tyre passes of 1, 6, 11 and 16, and three soil moisture contents of 8%, 11% and 14% soil compaction was evaluated measuring soil bulk density and soil sinkage. Experiments were conducted in the soil bin at the Urmia University under a single trector’s tire 220/65 R 21l under a constant load of 4 kN, inflation pressure of 110 kPa and at a forward velocity of 2.88 km hr-1. It was found that at manure rate of of 90 ton ha-1, comparing to no-manure treatment, soil bulk density and soil sinkage decreased by 14.7 and 6.94 percent, respectively. Also, increasing the number of tyre passes from 1 to 16 and increasing soil moisture content from 8 to 14 percent, increased soil bulk density 7.21% and 7.92%, respectively. For neural network modeling multilayer perceptron network with six neurons in the hidden layer with sigmoid transfer function and linear transfer function for the output neuron was used. Comparison of neural network output and experimental results showed high correletion with correlation coefficient of R= 0.99 between them. The mean square error (MSE) of the model and mean absolute percentage error of the system (MAPE) were 0.0119071 and 0.0009641,respectivly, which showed high accuracy of neural network to model soil compaction.
Payam Farhadi; Abdollah Golmohammadi; Ahmad Sharifi-Malvajerdi; Gholamhossein Shahgholi
Abstract
In this study, a single tire tester was used to study the effects of vertical load, inflation pressure and moisture content on tire rolling resistance in a soil bin. A Goodyear 12.4-28, 6 ply tractor drive tire was employed and the soil texture was a clay loam. The experimental design was a completely ...
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In this study, a single tire tester was used to study the effects of vertical load, inflation pressure and moisture content on tire rolling resistance in a soil bin. A Goodyear 12.4-28, 6 ply tractor drive tire was employed and the soil texture was a clay loam. The experimental design was a completely randomized with factorial layout at three replications. A multivariate regression model was obtained with the correlation coefficient of R2=0.85 to predict the tire rolling resistance based on vertical load, inflation pressure, and moisture content. A multilayer feed-forward ANN (artificial neural network) with standard BP (back propagation) algorithm and LM (Levenberg-Marquardt) training function by using of two hidden layer in the network architecture was employed. RMSE (root mean squared error) and R2 was used as modeling performance criteria. Tire inflation pressure was identified as the controller parameter of tire rolling resistance at low moisture content and also moisture content was the most effective parameter on changing of rolling resistance in regression model. Also the obtained R2=0.977 from ANN model showed that ANN data were more close to actual data than the regression model.
Payam Farhadi; Abdollah Golmohammadi; Ahmad Sharifi-Malvajerdi; Gholamhossein Shahgholi
Abstract
One of the most important issues in agricultural machinery section is tyre - soil interactions. In this study, a single wheel tester was used to follow experiments in controlled conditions in a soil bin. A Goodyear 12.4-28, 6 ply tractor drive tyre was operated at three vertical loads of 6, 9 and 12 ...
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One of the most important issues in agricultural machinery section is tyre - soil interactions. In this study, a single wheel tester was used to follow experiments in controlled conditions in a soil bin. A Goodyear 12.4-28, 6 ply tractor drive tyre was operated at three vertical loads of 6, 9 and 12 kN, three inflation pressures of 80, 120 and 160 kPa and three moisture content of soil: 11.20, 14.86 and 18.68 % d.b to investigate the effect of the variables on these parameters: contact area, contact pressure, compaction, and soil apparent electrical conductivity. It was found that medium contact pressure had a direct relation with vertical load, inflation pressure and moisture content. A regression model with R-square of 0.946 was achieved to predict contact pressure. Soil electrical conductivity changes was predicted with acceptable determination coefficient of 0.850 by using of vertical load, inflation pressure and moisture content. Determination coefficient magnitude for models to predict resistance to soil penetration (cone index) using soil apparent electrical conductivity decreased when moisture content was increased. The vertical load and inflation pressure were found two factors controlling the soil apparent electrical conductivity changes in low and high moisture content, respectively. Error percentage in using soil apparent electrical conductivity parameter to estimate the penetration resistance increased with increasing moisture content.
Sedaghat Fazeli; Yousef Abbaspour-Gilandeh; Gholamhosein Shahgoli; Zargham Fazel-Niari
Abstract
Traction efficiency and fuel consumption hgave close affinity and are considered to be important unit operations, especially during primary tillage operations. Therefore, analyzing factors that affect the amount of Traction efficiency and fuel consumption is considered important. Amongst these factors, ...
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Traction efficiency and fuel consumption hgave close affinity and are considered to be important unit operations, especially during primary tillage operations. Therefore, analyzing factors that affect the amount of Traction efficiency and fuel consumption is considered important. Amongst these factors, forward speed of tractor and tillage depth are of prime importance. Experiments were conducted for comparison of draft force and fuel consumption using, three types of cultivator blades (flat Duckfoot, Duckfoot with curve shank and Chisel plow), under sandy loam soil condition by using a factorial experiment based on randomized complete block design (RCBD). The effect of forward speed (3, 6.5 and 9 km/h) and tillage depth (10 and 20 cm) was the experimental conditions. Within each experimental plot, draft force of cultivators, fuel consumption, soil cone index, soil dispersion and percent of soil moisture content were measured.Analysis of variance showed that the effects of the blade type, forward speed and depth on the draft force and fuel consumption was significant at 1%. Comparing the draft force and fuel consumption of blades in different forward speeds and also considering the relatively light texture of the soil, it was found that duckfoot blade with curve shank with forward speed of 3 km/h was more appropriate.
Abstract
The current research investigated the draft force, soil disturbance area, specific draft, tractor fuel consumption, slippage of drive wheels, drawbar power, traction efficiency, and overall energy efficiency of subsoiling. The effects of forward speed (1.8, 2.3, 2.9 and 3.5 km/h) and depth (40 ...
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The current research investigated the draft force, soil disturbance area, specific draft, tractor fuel consumption, slippage of drive wheels, drawbar power, traction efficiency, and overall energy efficiency of subsoiling. The effects of forward speed (1.8, 2.3, 2.9 and 3.5 km/h) and depth (40 and 50 cm) on these parameters were evaluated using a randomized complete block design. An increase in forward speed increased draft force by 7%, specific draft by 15.4%, fuel consumption by 10%, wheel slippage by 2.9%, drawbar power by 108.3%, and overall energy efficiency by 6% and decreased soil disturbance area by 7.2% and traction efficiency 10%. Increasing the subsoiling depth increased the draft force by 21.3%, soil disturbance area by 25.6%, fuel consumption by 39.6%, wheel slippage by 2.8%, and drawbar power by 21.4% and decreased specific draft by 3.4%, traction efficiency by 6.7%, and overall energy efficiency by 1.4%. The most efficient operating settings were a working depth of 40 cm with a forward speed of 2.9 km/h.
