A Review on Application of Discrete Element Method in Soil Cutting Process

2013 ◽  
Vol 444-445 ◽  
pp. 1477-1482
Author(s):  
Ju Yang ◽  
Cheng Wu Wang ◽  
Feng Hua Wang ◽  
Xiao Jing Yang
Keyword(s):  
Discrete Element Method ◽  
Agricultural Production ◽  
Agricultural Soils ◽  
Discrete Element ◽  
Cutting Process ◽  
Basic Principles ◽  
Discrete Nature ◽  
Soil Cutting ◽  
External Forces ◽  
Element Method

Soil is one of the important mediators in the agricultural production and its particle is a discontinuous, heterogeneity and nonlinear natural geological substance. It is difficult to analyze the soil cutting process by using traditional methods. According to the discrete nature of the agricultural soils, discrete element method based on the discontinuity assumptions can be an alternative to analyze the changes under external forces in the soil cutting process. This article describes the basic principles, its applications and its prospects of the discrete element method, especially in the field of soil cutting.

scholarly journals Study on the Interaction between Soil and the Five-Claw Combination of a Mole Using the Discrete Element Method

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Yuwan Yang ◽  
Mo Li ◽  
Jin Tong ◽  
Yunhai Ma
Keyword(s):  
Discrete Element Method ◽  
Discrete Element ◽  
Rake Angle ◽  
Soil Resistance ◽  
Distance Ratio ◽  
Soil Failure ◽  
Soil Cutting ◽  
Soil Bin ◽  
Rupture Distance ◽  
Element Method

A mole is a born digger spending its entire existence digging tunnels. The five claws of a mole’s hand are combinative to cut soil powerfully and efficiently. However, little was known in detail about the interaction between the soil and the five-claw combination. In this study, we simulated the soil cutting process of the five-claw combination using the discrete element method (DEM) as an attempt for the potential design of soil-engaging tools to reduce soil resistance. The five-claw combination moved horizontally in the soil bin. Soil forces (draught and vertical forces) and soil failure (soil rupture distance ratio) were measured at different rake angles and speeds. Results showed that the draught and vertical forces varied nonlinearly as the rake angle increased from 10 to 90°, and both changed linearly with the speed increasing from 1 to 5 m/s. The curve of the soil rupture distance ratio with rake angles could be better described using a quadric function, but the speed had little effect on the soil rupture distance ratio. Notably, the soil rupture distance ratio of the five-claw combination in simulation was on average 19.6% lower than the predicted ratio of simple blades at different rake angles indicating that the five-claw combination could make less soil failure and thereby produce lower soil resistance. Given the draught and vertical forces, the performance of the five-claw combination was optimized at the rake angle of 30°.

scholarly journals MAIZE STRAW CUTTING PROCESS MODELLING AND PARAMETER CALIBRATION BASED ON DISCRETE ELEMENT METHOD (DEM)

2021 ◽  
pp. 461-468
Keyword(s):  
Discrete Element Method ◽  
Shear Stiffness ◽  
Discrete Element ◽  
Cutting Process ◽  
Cutting Resistance ◽  
Maize Straw ◽  
Cutting Effect ◽  
Cutting Experiment ◽  
Cutting Model ◽  
Element Method

In order to simulate straw cutting process, this paper established a maize straw cutting model with discrete element method (DEM) based on straw cutting experiment. Firstly, maize straw model consisting of several small particles was established by DEM. Then, a straw cutting experiment was conducted and the maximum straw cutting resistance was 199 N for straw with 15 mm diameter. Then, single-factor experiment was conducted to analyze the effect of DEM parameters on straw cutting effect and the max straw cutting resistance Fmax. The normal stiffness between particles and blade (ball-facet-kn) and shear stiffness between particles and blade (ball-facet-ks) were found to be the significant factors affecting Fmax, and the value of the parameters that has no significance was determined. The optimum combination of the significant parameters was 17662 N·m-1 of ball-facet-kn and 52499 N·m-1 of ball-facet-ks. The verification test results showed that the maize straw model was cut off, thus it could simulate the real straw cutting effect, and the relative error of max straw cutting resistance Fmax between the simulation and the experiment was below 9.1%. Thus, it could be concluded that the established maize straw cutting model was accurate and reliable.

scholarly journals Crack nucleation in solid materials under external load - simulations with the Discrete Element Method

2018 ◽  
Vol 165 ◽  
pp. 22019
Author(s):  
Piotr Klejment ◽  
Wojciech Dębski
Keyword(s):  
Boundary Conditions ◽  
Discrete Element Method ◽  
Crack Nucleation ◽  
Numerical Technique ◽  
Three Dimensional ◽  
Solid Material ◽  
Discrete Element ◽  
Biological Tissues ◽  
External Forces ◽  
Element Method

Numerical analysis of cracking processes require an appropriate numerical technique. Classical engineering approach to the problem has its roots in the continuum mechanics and is based mainly on the Finite Element Method. This technique allows simulations of both elastic and large deformation processes, so it is very popular in the engineering applications. However, a final effect of cracking - fragmentation of an object at hand can hardly be described by this approach in a numerically efficient way since it requires a solution of a problem of nontrivial evolving in time boundary conditions. We focused our attention on the Discrete Element Method (DEM), which by definition implies “molecular” construction of the matter. The basic idea behind DEM is to represent an investigated body as an assemblage of discrete particles interacting with each other. Breaking interaction bonds between particles induced by external forces imeditelly implies creation/evolution of boundary conditions. In this study we used the DEM approach to simulate cracking process in the three dimensional solid material under external tension. The used numerical model, although higly simplified, can be used to describe behaviour of such materials like thin films, biological tissues, metal coatings, to name a few.

scholarly journals MAIZE STRAW CUTTING PROCESS MODELLING AND PARAMETER CALIBRATION BASED ON DISCRETE ELEMENT METHOD (DEM)

2021 ◽  
pp. 461-468
Author(s):  
Zhiqi Zheng ◽  
Hongbo Zhao ◽  
Peng Liu ◽  
Jin He
Keyword(s):  
Discrete Element Method ◽  
Shear Stiffness ◽  
Discrete Element ◽  
Cutting Process ◽  
Cutting Resistance ◽  
Maize Straw ◽  
Cutting Effect ◽  
Cutting Experiment ◽  
Cutting Model ◽  
Element Method

In order to simulate straw cutting process, this paper established a maize straw cutting model with discrete element method (DEM) based on straw cutting experiment. Firstly, maize straw model consisting of several small particles was established by DEM. Then, a straw cutting experiment was conducted and the maximum straw cutting resistance was 199 N for straw with 15 mm diameter. Then, single-factor experiment was conducted to analyze the effect of DEM parameters on straw cutting effect and the max straw cutting resistance Fmax. The normal stiffness between particles and blade (ball-facet-kn) and shear stiffness between particles and blade (ball-facet-ks) were found to be the significant factors affecting Fmax, and the value of the parameters that has no significance was determined. The optimum combination of the significant parameters was 17662 N·m-1 of ball-facet-kn and 52499 N·m-1 of ball-facet-ks. The verification test results showed that the maize straw model was cut off, thus it could simulate the real straw cutting effect, and the relative error of max straw cutting resistance Fmax between the simulation and the experiment was below 9.1%. Thus, it could be concluded that the established maize straw cutting model was accurate and reliable.

Discrete element method to model cracking for two layer systems

TAPPI Journal ◽  
2019 ◽  
Vol 18 (2) ◽  
pp. 101-108
Author(s):  
Daniel Varney ◽  
Douglas Bousfield
Keyword(s):  
Discrete Element Method ◽  
Flexural Modulus ◽  
Single Layer ◽  
Discrete Element ◽  
Flexural Stress ◽  
Layer System ◽  
Three Point Bending ◽  
Moving Force ◽  
Coating Layers ◽  
Element Method

Cracking at the fold is a serious issue for many grades of coated paper and coated board. Some recent work has suggested methods to minimize this problem by using two or more coating layers of different properties. A discrete element method (DEM) has been used to model deformation events for single layer coating systems such as in-plain and out-of-plain tension, three-point bending, and a novel moving force picking simulation, but nothing has been reported related to multiple coating layers. In this paper, a DEM model has been expanded to predict the three-point bending response of a two-layer system. The main factors evaluated include the use of different binder systems in each layer and the ratio of the bottom and top layer weights. As in the past, the properties of the binder and the binder concentration are input parameters. The model can predict crack formation that is a function of these two sets of factors. In addition, the model can predict the flexural modulus, the maximum flexural stress, and the strain-at-failure. The predictions are qualitatively compared with experimental results reported in the literature.

Sign in / Sign up

Export Citation Format

Share Document