Investigating the Interaction between Soil and Cultivator Blade by Numerical Simulation and Validation of Results by Soil Bin Tests

Document Type : Research Article

Authors

• H. Mahboub Yangeje
• A. Mardani

Department of Mechanical Engineering of Biosystems, Faculty of Agriculture, Urmia University, Urmia, Iran.

https://doi.org/10.22067/jam.2021.70572.1041

Abstract

Introduction
Seedbed preparation, seeding, and transplanting are usually based on mechanical soil tillage. Tillage by cutting, mixing, overturning, and loosening the soil can modify the physical, mechanical, and biological properties of soil. These days, because of soil protection, the use of tillage tools is less and less recommended, and some implements such as cultivators are preferred to primary tillage tools such as plows. Experimental study of soil-tool interaction and field measurements of the mechanics of tillage tools are usually time-consuming and costly. On the other hand, the variety of variables and uncontrolled conditions add other dimensions to the complexity of this method. Also, the experimental and analytical methods do not have a comprehensive view of stress distribution and soil deformation in the soil-tool interaction process.
Materials and Methods
The main purpose of this study is to validate the results of numerical simulations in two phases of experimental tests: in soil bin environment and in finite element computer simulations. Experimental tests were performed in the soil bin environment of the Department of Mechanical Engineering of Biosystems, Urmia University, which has a soil bin facility with dimensions of length and width of 24 and 2 m, respectively, and has clay loam soil. Before experimental tests, soil preparation was performed by using some special tillage implements (harrow, leveler, and roller) which were attached to the soil bin (Figure.1). For experimental tests, a mechanism set consisting of two cultivator blades with a width of 15cm, a length of 20cm, and at a spacing of 35cm from each other was prepared and constructed. The relevant mechanism is designed to have the ability to change the tillage depth. Data were collected at three different soil depth levels of 6, 10, and 14cm in the soil bin with three replications. Data recording was performed using a 10-channel data logger with load cell connectivity and data storage ability. Also, in this study, the Drucker-Prager model as a finite element simulation method was used to calculate the stress during the soil-tool relationship. ABAQUS 6.10.1 software was used to simulate the cultivator tine. To solve the problem, the soil parameters were defined as presented in Table 1, and then the interaction between the soil-tool model and the necessary constraints, including boundary conditions, were defined. In the next step, meshing was applied to the constructed model.
Results and Discussion
In the results section, first, the results related to the amount of traction force required for the tillage tine in the simulation were calculated and then compared with the soil bin experimental tests. The traction force of the finite element simulation results for three tillage depths of 6, 10, and 14 cm in three principal directions is shown in Figure 4. A comparison of simulation and experimental results showed that there is a good agreement between them. In comparison, the simulation error range of the three depths of 6, 10, and 14 cm has shown 7.3, 5.6, and 4.16% at a speed of 2.5 kmh^-1, respectively, as the velocity studied in this research. In the next section, the results of stress distribution contours in the soil and finally the overlap of the blade effect were discussed. Figure 6 shows the status of stress contours at three depths. By increasing the depth of the tine at the three depth levels studied, the stress range is shifted from the soil surface to its depth. For this purpose, at the maximum depth studied in this study (14 cm), it shows that the stress propagation to the soil surface is less than at other depths. Also, with decreasing depth, for a depth of 6 cm, the maximum stress was on the top soil surface, in other words, more deformation was seen on the soil surface.
Conclusion
Comparing the simulation results for predicting traction force with the results of experimental tests has led to relatively acceptable results and the maximum traction force prediction error at different depths has been about 7.3%.
The distribution of stress in the soil was observed due to the tine depth. The highest intensity of stress propagation was observed at the soil surface; and the highest soil surface deformation at a depth of 6 cm. With increasing depth, both parameters of stress and soil surface deformation have decreased. According to the results of the studied blades, it is better to use these types of tillage tools only at lower depths. Also, in evaluating the overlap of the soil loosening zone in the side-by-side tines, it proves the superiority of the tine performance at lower depths.

Keywords

• Chisel plow
• Finite element method (FEM)
• Soil bin
• Soil- tine interaction

20.1001.1.22286829.1401.12.4.10.6

Main Subjects

• The relationship between machine and soil

Open Access

©2021 The author(s). This article is licensed under Creative Commons Attribution 4.0 International License (CC BY 4.0), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source.

References

1. Asaf, Z., Rubinstein, D., & Shmulevich, I. (2007). Determination of discrete element model parameters required for soil tillage. Soil and Tillage Research, 92(1-2): 227-242. https://doi.org/10.1016/j.still.2006.03.006
2. Azimi-Nejadian, H., Karparvarfard, S. H., Naderi-Boldaji, M., & Rahmanian-Koushkaki, H. (2019). Combined finite element and statistical models for predicting force components on a cylindrical mouldboard plough. Biosystems Engineering, 186, 168-181. https://doi.org/10.1016/j.Biosystemseng.2019.07.007
3. Birkás, M. (2009). Classic cultivation requirements and the need of reducing climatic damage. Növénytermelés, 58(2): 123-134. https://doi.org/10.1556/novenyterm.58.2009.2.8
4. Busari, M. A., Kukal, S. S., Kaur, A., Bhatt, R., & Dulazi, A. A. (2015). Conservation tillage impacts on soil, crop and the environment. International Soil and Water Conservation Research, 3(2), 119-129.‏ https://doi.org/10.1016/j.iswcr.2015.05.002
5. Godwin, R. J., & Spoor, G. 1977. Soil failure with narrow tines. Journal of Agricultural Engineering Research, 22(3), 213-228. https://doi.org/10.1016/0021-8634(77)90044-0
6. Ibrahmi, A., Bentaher, H., Hamza, E., Maalej, A., & Mouazen, A. M. (2015). Study the effect of tool geometry and operational conditions on mouldboard plough forces and energy requirement: Part 2. Experimental validation with soil bin test. Computers and Electronics in Agriculture, 117, 268-275. https://doi.org/10.1016/j.compag.2015.08.004
7. Kešner, A., Chotěborský, R., Linda, M., Hromasová, M., Katinas, E., & Sutanto, H. (2021). Stress distribution on a soil tillage machine frame segment with a chisel shank simulated using discrete element and finite element methods and validate by experiment. Biosystems Engineering, 209, 125-138. https://doi.org/10.1016/j.biosystemseng.2021.06.012
8. Kushwaha, R. L., & Shen, J. (1995). Finite element analysis of the dynamic interaction between soil and tillage tool. Transactions of the ASAE, 38(5), 1315-1319. https://elibrary.asabe.org/abstract.asp?aid=27953
9. Kushwaha, R. L., & Zhang, Z. X. (1998). Evaluation of factors and current approaches related to computerized design of tillage tools: a review. Journal of Terramechanics, 35(2), 69-86. https://doi.org/10.1016/S0022-4898(98)00013-5
10. Liu, Z., Liu, K., Ma, Z., Ni, F., & Gu, L. (2021). Mechanical responses and fracture mechanism of rock with different free surfaces under the chisel pick cutting. Engineering Fracture Mechanics, 247, 1-16.
11. Mardani, A., Shahidi, K., & Karim-Maslak, H. (2010). An indoor traction measurement system to facilitate research on agricultural tires. Journal of Food, Agriculture and Environment, 8(2), 642-646.
12. McKyes, E. (Ed.). (1985). Soil cutting and tillage. Elsevier. p 216.
13. Mouazen, A. M., & Neményi, M. (1999). Finite element analysis of subsoiler cutting in non-homogeneous sandy loam soil. Soil and Tillage Research, 51(1-2), 1-15. https://doi.org/10.1016/S0167-1987(99)00015-X
14. Sadeghnejad, H., & Islami, K. (2006). Comparison of wheat yield by changing the tillage method. Agricultural Sciences, 12(1), 103-112. (in Persian).
15. Shao, Y., Xie, Y., Wang, C., Yue, J., Yao, Y., Li, X., ... & Guo, T. (2016). Effects of different soil conservation tillage approaches on soil nutrients, water use and wheat-maize yield in rainfed dry-land regions of North China. European Journal of Agronomy, 81, 37-45.‏ https://doi.org/10.1016/j.eja.2016.08.014
16. Shmulevich, I., Asaf, Z., & Rubinstein, D. (2007). Interaction between soil and a wide cutting blade using the discrete element method. Soil and Tillage Research, 97(1), 37-50. https://doi.org/10.1016/j.still.2007.08.009
17. Smatana, J., Macák, M., & Demjanová, E. (2010). The influence of different tillage practices on soil physical characteristics. Research Journal of Agricultural Science, 42(3), 315-319.
18. Tamás, K., Jóri, I. J., & Mouazen, A. M. (2013). Modelling soil–sweep interaction with discrete element method. Soil and Tillage Research, 134, 223-231. https://doi.org/10.1016/j.still.2013.09.001
19. Ucgul, M., & Saunders, C. (2020). Simulation of tillage forces and furrow profile during soil-mouldboard plough interaction using discrete element modelling. Biosystems Engineering, 190, 58-70. https://doi.org/10.1016/j.biosystemseng.2019.11.022
20. Várallyay, G. (2010). The role of soil resilience in sustainable Növénytermelés, 59 (Supplement): 173-176.