Discrete Element Analysis Models Research Articles

Understanding recurrent groin pain following periacetabular osteotomy: assessment of psoas tendon mechanics using discrete element analysis

ABSTRACT Recurrent groin pain following periacetabular osteotomy (PAO) is a challenging problem. The purpose of our study was to evaluate the position and dynamics of the psoas tendon as a potential cause for recurrent groin pain following PAO. A total of 386 PAO procedures, performed between January 2013 and January 2020, were identified from a single surgeon series. Thirteen patients (18 hips) had a psoas tendinopathy, as confirmed with relief of symptoms following a diagnostic injection into the psoas tendon. All patients underwent computed tomography (CT) scans pre- and post-operatively. The data from CT scan was used to manually segment bony structures and create 3D models using Mimics software (Materialise NV). A validated discrete element analysis model using rigid body springs was used to predict psoas tendon movement during hip circumduction and walking. The distance of the iliopsoas tendon to any bony abnormality was calculated. All computational analyses were performed using MATLAB software. Thirteen hips (13/18) showed bony malformations (spurs, hypertrophic callus or delayed union and malunion) secondary to callus at the superior pubic ramus. The mean minimal distance of the iliopsoas tendon to osteotomy site was found to be 13.73 mm (σ = 3.09) for spurs, 10.99 mm (σ = 2.85) for hypertrophic callus and 11.91 mm (σ = 2.55) for canyon type. In normal bony healing, the mean minimal distance was 18.55 mm (σ = 4.11). Using a validated computational modelling technique, this study has demonstrated three different types of malformation around the superior pubic osteotomy site, which are associated with psoas impingement. In all of the cases, the minimal distance of the iliopsoas tendon to the osteotomy site was reduced by 59–74%, as compared with the normal anatomy.

Incorporating patient-specific hip orientation from weightbearing computed tomography affects discrete element analysis-computed regional joint contact mechanics in individuals treated with periacetabular osteotomy for hip dysplasia.

Computational models of the hip often omit patient-specific functional orientation when placing imaging-derived bony geometry into anatomic landmark-based coordinate systems for application of joint loading schemes. The purpose of this study was to determine if this omission meaningfully alters computed contact mechanics. Discrete element analysis models were created from non-weightbearing (NWB) clinical CT scans of 10 hip dysplasia patients (11 hips) and oriented in the International Society of Biomechanics (ISB) coordinate system (NWB-ISB). Three additional models were generated for each hip by adding patient-specific stance information obtained via weightbearing CT (WBCT) to each ISB-oriented model: (1) patient-specific sagittal tilt added (WBCT-sagittal), (2) coronal and axial rotation from optical motion capture added to (1; WBCT-combo), and (3) WBCT-derived axial, sagittal, and coronal rotation added to (1; WBCT-original). Identical gait cycle loading was applied to all models for a given hip, and computed contact stress and contact area were compared between model initialization techniques. Addition of sagittal tilt did not significantly change whole-joint peak (p = 0.922) or mean (p = 0.871) contact stress or contact area (p = 0.638). Inclusion of motion-captured coronal and axial rotation (WBCT-combo) decreased peak contact stress (p = 0.014) and slightly increased average contact area (p = 0.071) from WBCT-sagittal models. Including all WBCT-derived rotations (WBCT-original) further reduced computed peak contact stress (p = 0.001) and significantly increased contact area (p = 0.001). Variably significant differences (p = 0.001-1.0) in patient-specific acetabular subregion mechanics indicate the importance of functional orientation incorporation for modeling applications in which local contact mechanics are of interest.

Validation of a personalized ligament-constraining discrete element framework for computing ankle joint contact mechanics

Background and ObjectiveComputer simulations of joint contact mechanics have great merit to improve our current understanding of articular ankle pathology. Owed to its computational simplicity, discrete element analysis (DEA) is an encouraging alternative to finite element analysis (FEA). However, previous DEA models lack subject-specific anatomy and may oversimplify the biomechanics of the ankle. The objective of this study was to develop and validate a personalized DEA framework that permits movement of the fibula and incorporates personalized cartilage thickness as well as ligamentous constraints. MethodsA linear and non-linear DEA framework, representing cartilage as compressive springs, was established, verified, and validated. Three-dimensional (3D) bony ankle models were constructed from cadaveric lower limb CT scans imaged during application of weight (85 kg) and/or torque (10 Nm). These 3D models were used to generate cartilage thickness and ligament insertion sites based on a previously validated statistical shape model. Ligaments were modelled as non-linear tension-only springs. Validation of contact stress prediction was performed using a simple, axially constrained tibiotalar DEA model against an equivalent FEA model. Validation of ligamentous constraints compared the final position of the ankle mortise to that of the cadaver after application of torque and sequential ligament sectioning. Finally, a combined ligamentous-constraining DEA model was validated for predicted contact stress against an equivalent ligament-constraining FEA model. ResultsThe linear and non-linear DEA model reproduced a mean articular contact stress within 0.36 MPa and 0.39 MPa of the FEA calculated stress, respectively. With respect to the ligamentous validation, the DEA ligament-balancing algorithm could reproduce the position of the distal fibula within the ankle mortise to within 0.97 mm of the experimental observed distal fibula. When combining the ligament-constraining and contact stress algorithm, DEA was able to reproduce a mean articular contact stress to within 0.50 MPa of the FEA calculated contact stress. ConclusionThe DEA framework presented herein offers a computationally efficient alternative to FEA for the prediction of contact stress in the ankle joint, manifesting its potential to enhance the mechanical understanding of articular ankle pathologies on both a patient-specific and population-wide level. The novelty of this model lies in its personalized nature, inclusion of the distal tibiofibular joint and the use of non-linear ligament balancing to maintain the physiological ankle joint articulation.

A DEM-Based Modeling Method and Simulation Parameter Selection for Cyperus esculentus Seeds

To build a DEM model of Cyperus esculentus seed particles, the shape and size of the Cyperus esculentus seed particles were measured and analyzed. The results showed that the dispersity in size had a normal distribution. Additionally, a certain functional relationship between the primary dimension and secondary dimensions was determined. The width of the seed was the primary dimension, and the other secondary dimensions (length and thickness) were calculated based on their relationships with the primary dimension. On this basis, an approach for modeling Cyperus esculentus seed particles based on the multi-sphere (MS) method was proposed. The discrete element analysis models of three varieties of Cyperus esculentus seeds were established with different numbers of filing spheres. Moreover, to obtain more accurate simulation parameters, first, a range of values of the simulation parameters was obtained by the experimental method. Second, the Plackett–Burman (PB) test and the path of steepest ascent method were both adopted to correct and calibrate the simulation parameters, which were difficult to obtain through experiments, and simulation of the direct shear test was used for calibration. All of the methods guaranteed that the selected parameters were reasonable. The test results showed that the static friction coefficient of seed–seed had a significant effect on the simulation results. Finally, piling tests and the bulk density test were used for modeling verification. By comparing the simulated results and experimental results in the piling tests and bulk density test, when the number of filing spheres increased, the simulated results were close to those obtained experimentally. Therefore, the feasibility and validity of the modeling method for Cyperus esculentus seed particles that we proposed and the simulation parameters that were obtained were verified.

Study on the modeling method of sunflower seed particles based on the discrete element method

A modeling and simulation method was developed to comprehensively describe and build discrete element model for non-spherical particles based on the discrete element method (DEM). To popularize the application of sunflower seeds in computer digital simulation technology, the motion patterns and dynamic response characteristics of sunflower seeds in key processes such as sowing and harvesting are explored with the help of discrete element analysis methods to optimize the dimensional parameters and structural performance of related mechanical components. This paper takes edible sunflower seeds 1013 as the research object, and proposes a discrete element analysis model building method for individual sunflower seeds and groups of sunflower seeds particles by testing and analyzing the triaxial dimensions and three-dimensional volumes of sunflower seeds and the shape simplification of the seeds. 6 sunflower seed multi-sphere models (25 sub-spheres, 28 sub-spheres, 31 sub-spheres, 34 sub-spheres, 37 sub-spheres, 40 sub-spheres) with different accuracy and 2 sunflower seed polyhedral models (cuboid and triangle pyramid) with different shapes were established using the multi-sphere and polyhedron filling methods. The physical tests and angle of repose simulation tests were applied to measure and calibrate the intrinsic parameters and contact parameters of sunflower seeds. The physical test results of the bulk density and angle of repose are compared with the simulation test results to verify the feasibility of the discrete element modeling method for sunflower seeds proposed in this paper. The results show that the simulation results of bulk density and angle of repose are closer to the experimental results when the multi-sphere model is 31 sub-spheres and the polyhedral model is cuboid, considering fewer spheres and faster simulation rates. And the accuracy and applicability of the discrete element model and parameters of sunflower seeds are further verified through the simulation test of the productivity of the spiral conveying device of the 4ZXRKS-4 sunflower combine harvester test bed.

Research on dynamic mechanical behavior of ballast bed in windblown sand railway based on dimensional analysis

Railway operation is faced with windblown sand hazards in desert areas. In order to study the influence of sand intrusion on dynamic mechanical behavior of railway ballast bed, a multi-scale discrete element model of sleeper-ballast bed-surface layer of subgrade has been established with the method of “step filling-particle replacement”. The vibration acceleration of the ballast bed and the dynamic displacement of sleeper field tests in the section with severe sandstorm have carried out to verify the correctness of discrete element analysis model. The scale invariance of the linear contact model and the rationality of the scaling of the sand size are explained by the “dimensional analysis method”. The results show that the sand intrusion reduces the vibration of ballast bed. When the sand content reaches 30%, the vibration and elastic deformation of ballast bed decrease by 94.2% and 63.2% respectively. The invasion of sand can reduce the deformation of the surface layer of subgrade, and the maximum reduction is 53.3%. Therefore, it is necessary to pay attention to the service state of ballast bed with sand content of 30% in windblown sand area, and make the maintenance plan reasonably.

Discrete element and finite element methods provide similar estimations for hip joint contact mechanics during walking gait

Finite element analysis (FEA) provides a powerful approach for estimating the in-vivo loading characteristics of the hip joint during various locomotory and functional activities. However, time-consuming procedures, such as the generation of high-quality FE meshes and setup of FE simulation, typically make the method impractical for rapid applications which could be used in clinical routine. Alternatively, discrete element analysis (DEA) has been developed to quantify mechanical conditions of the hip joint in a fraction of time compared to FEA. Although DEA has proven effective in the estimation of contact stresses and areas in various complex applications, it has not yet been well characterised by its ability to evaluate contact mechanics for the hip joint during gait cycle loading using data from several individuals. The objective of this work was to compare DEA modelling against well-established FEA for analysing contact mechanics of the hip joint during walking gait. Subject-specific models were generated from magnetic resonance images of the hip joints in five asymptomatic subjects. The DEA and FEA models were then simulated for 13 loading time-points extracted from a full gait cycle. Computationally, DEA was substantially more efficient compared to FEA (simulation times of seconds vs. hours). The DEA and FEA methods had similar predictions for contact pressure distribution for the hip joint during normal walking. In all 13 simulated loading time-points across five subjects, the maximum difference in average contact pressures between DEA and FEA was within ±0.06 MPa. Furthermore, the difference in contact area ratio computed using DEA and FEA was less than ±6%.

Study on Creep Behavior Of Asphalt Mixture Based on Discrete Element Method

A three-dimensional (3D) microstructure-based discrete element (DE) model was developed to study the creep behaviour of high viscoelastic asphalt sand (HVAS) with the uniaxial compression creep tests. The three-point bending creep tests of asphalt mortar were carried out in order to obtain the parameters of the Burger model, to determine the transformation method of macroscopic parameters and microscopic parameters of the model in theory, to obtain the parameters used in the discrete element model, and then establish the discrete element analysis model for the asphalt mixture. A 3D-DE digital specimen was composed of coarse aggregates, asphalt mortar and air voids, which could also take gradation, irregular shape, random distribution of aggregate and air voids into consideration, and the boundary conditions of the model were set through the simulation of the uniaxial compression creep tests. An accurate and extensive mapping model of HVAS was built by 3D-PFC (Particle Flow Code), which can provide a simple alternative to the laboratory tests. This method can simulate a series of numerical examples based on different stress levels, coarse aggregate homogenizations, mortar homogenizations and temperatures in a single factor method. Comparison of results of laboratory and numerical tests shows that the 3D-PFC-viscoelastic model can reflect the creep mechanical behaviour of asphalt mixture accurately. It provides the theoretical basis and auxiliary means for analysing the mechanical properties of asphalt mixtures using PFC software. The research on creep behaviour of the asphalt mixture by numerical simulation opens up a new way for the research on creep behaviour of the asphalt mixture, it is of considerable theoretical value and has broad application prospects.

A Combined Geometric Morphometric and Discrete Element Modeling Approach for Hip Cartilage Contact Mechanics

Finite element analysis (FEA) provides the current reference standard for numerical simulation of hip cartilage contact mechanics. Unfortunately, the development of subject-specific FEA models is a laborious process. Owed to its simplicity, Discrete Element Analysis (DEA) provides an attractive alternative to FEA. Advancements in computational morphometrics, specifically statistical shape modeling (SSM), provide the opportunity to predict cartilage anatomy without image segmentation, which could be integrated with DEA to provide an efficient platform to predict cartilage contact stresses in large populations. The objective of this study was, first, to validate linear and non-linear DEA against a previously validated FEA model and, second, to present and evaluate the applicability of a novel population-averaged cartilage geometry prediction method against previously used methods to estimate cartilage anatomy. The population-averaged method is based on average cartilage thickness maps and therefore allows for a more accurate and individualized cartilage geometry estimation when combined with SSM. The root mean squared error of the population-averaged cartilage geometry predicted by SSM as compared to the manually segmented cartilage geometry was 0.31 ± 0.08 mm. Identical boundary and loading conditions were applied to the DEA and FEA models. Predicted DEA stress distribution patterns and magnitude of peak stresses were in better agreement with FEA for the novel cartilage anatomy prediction method as compared to commonly used parametric methods based on the estimation of acetabular and femoral head radius. Still, contact stress was overestimated and contact area was underestimated for all cartilage anatomy prediction methods. Linear and non-linear DEA methods differed mainly in peak stress results with the non-linear definition being more sensitive to detection of high peak stresses. In conclusion, DEA in combination with the novel population-averaged cartilage anatomy prediction method provided accurate predictions while offering an efficient platform to conduct population-wide analyses of hip contact mechanics.

Discrete Element Modeling and Simulation of Soybean Seed Using Multi-Spheres and Super-Ellipsoids

The accuracy of particle shape characterization is the key to the study of particle dynamics. This study proposes two modeling methods, super-ellipsoid approach (SE) and multi-sphere approach (MS), to describe the discrete element method (DEM) model of soybean seeds with the goal of improving the accuracy of the discrete element analysis model of soybean seeds. The accumulation process, flow behavior, and mixing characteristics of soybean seeds were studied through experiments and DEM simulation. Three comparative verification tests were carried out to compare the accuracy and potential similarity of the SE particle model and the MS particle model: (1) angle of repose experiment; (2) slope screening experiment; and (3) horizontal rotating cylinder experiment. The simulation and experimental results indicated that when compared with the MS particle model, the soybean seed model established using the super-ellipsoid approach can make the described particle shape more accurate, and also reproduce the accumulation process, flow behavior, and mixing characteristics of soybean seeds more accurately. For the multi-sphere approach, the calculation cost for approximating the DEM model of soybean seeds can be saved when the number of sub-spheres is less, but the accuracy of the particle model will be reduced at the same time. In this paper, the DEM model established using the super-ellipsoid approach can accurately simulate the real movement of soybean seeds. Therefore, the model can provide a new numerical calculation method for the simulation of the particle system in the structure of agricultural machinery.

Development and validation of a kinematically-driven discrete element model of the patellofemoral joint

Quantifying the complex loads at the patellofemoral joint (PFJ) is vital to understanding the development of PFJ pain and osteoarthritis. Discrete element analysis (DEA) is a computationally efficient method to estimate cartilage contact stresses with potential application at the PFJ to better understand PFJ mechanics. The current study validated a DEA modeling framework driven by PFJ kinematics to predict experimentally-measured PFJ contact stress distributions. Two cadaveric knee specimens underwent quadriceps muscle [215 N] and joint compression [350 N] forces at ten discrete knee positions representing PFJ positions during early gait while measured PFJ kinematics were used to drive specimen-specific DEA models. DEA-computed contact stress and area were compared to experimentally-measured data. There was good agreement between computed and measured mean and peak stress across the specimens and positions (r = 0.63–0.85). DEA-computed mean stress was within an average of 12% (range: 1–47%) of the experimentally-measured mean stress while DEA-computed peak stress was within an average of 22% (range: 1–40%). Stress magnitudes were within the ranges measured (0.17–1.26 MPa computationally vs 0.12–1.13 MPa experimentally). DEA-computed areas overestimated measured areas (average error = 60%; range: 4–117%) with magnitudes ranging from 139 to 307 mm2 computationally vs 74–194 mm2 experimentally. DEA estimates of the ratio of lateral to medial patellofemoral stress distribution predicted the experimental data well (mean error = 15%) with minimal measurement bias. These results indicate that kinematically-driven DEA models can provide good estimates of relative changes in PFJ contact stress.

Joint contact stresses calculated for acetabular dysplasia patients using discrete element analysis are significantly influenced by the applied gait pattern

Gait modifications in acetabular dysplasia patients may influence cartilage contact stress patterns within the hip joint, with serious implications for clinical outcomes and the risk of developing osteoarthritis. The objective of this study was to understand how the gait pattern used to load computational models of dysplastic hips influences computed joint mechanics. Three-dimensional pre- and post-operative hip models of thirty patients previously treated for hip dysplasia with periacetabular osteotomy (PAO) were developed for performing discrete element analysis (DEA). Using DEA, contact stress patterns were calculated for each pre- and post-operative hip model when loaded with an instrumented total hip, a dysplastic, a matched control, and a normal gait pattern. DEA models loaded with the dysplastic and matched control gait patterns had significantly higher (p = 0.012 and p < 0.001) average pre-operative maximum contact stress than models loaded with the normal gait. Models loaded with the dysplastic and matched control gait patterns had nearly significantly higher (p = 0.051) and significantly higher (p = 0.008) average pre-operative contact stress, respectively, than models loaded with the instrumented hip gait. Following PAO, the average maximum contact stress for DEA models loaded with the dysplastic and matched control patterns decreased, which was significantly different (p < 0.001) from observed increases in maximum contact stress calculated when utilizing the instrumented hip and normal gait patterns. The correlation between change in DEA-computed maximum contact stress and the change in radiographic measurements of lateral center-edge angle were greatest (R2 = 0.330) when utilizing the dysplastic gait pattern. These results indicate that utilizing a dysplastic gait pattern to load DEA models may be a crucial element to capturing contact stress patterns most representative of this patient population.

3D Scanner-Based Corn Seed Modeling

<abstract> <b><sc>Abstract. </sc></b>Corn seed simulation modeling plays an important role in increasing the efficiency of corn production. Current research on corn seed modeling focuses on the development of 3D particle modeling methods. For efficient and precise modeling, on more corn seeds, in this article, a 3D scanner is introduced in the modeling method. Specifically, a combination of manual eight-sphere filling and automated spherical particle filling based on 3D scanner data is employed to build a long-range, simple 228-corn-seed discrete element analysis model. When compared with existing modeling methods, this model exhibits significantly improved precision and efficiency. In addition, simulation and analysis are performed on a typical agricultural corn facility (seed-metering device) to verify the feasibility of the proposed modeling method.

DEM Analysis of Lateral Ballast Resistance of Sleeper during Dynamic Stability Process under Different Vibration Frequency

Railway ballast dynamic stability operations is an important work in the line maintenance and repair operations, the selection of dynamic parameter is usually dependent on field trials and practical experience, for lack of theoretical basis. This paper creates discrete element analysis model of railway ballast using the discrete element method, the numerical simulations are carried out to study the lateral ballast resistance during dynamic stability process. We focus on the influence of vibration frequency during dynamic stability process; an optimal vibration frequency of the simulation analysis is obtained and compared with the recommended vibration frequency of a product of a China Railway Large Maintenance Machinery Company, it is found that the two vibration frequencies are basically consistent. This result verifies the correct validity of the discrete element analysis model of railway ballast during dynamic stability process.

Numerical Study Porosity of Railway Ballast during Tamping Process

Tamping operation is an important part of railway maintenance work. The porosity of railway ballast is an important maintenance quality evaluation index during tamping process. In this paper, based on the discrete characteristics of railway ballast, the discrete element analysis model of railway ballast is created using the discrete element method, numerical simulations are performed to study the evolution of porosity of railway ballast under sleeper during tamping process. This paper focuses on the influence of vibration frequency of tamping tines during tamping process; an optimal vibration frequency is obtained from the simulation and compared with the actual vibration frequency recommended by China Railway Large Maintenance Machinery Co., Ltd. Kunming, it is found that the two vibration frequency is consistent. This result verifies that the discrete element method is an effective method to study the evolution of porosity of railway ballast during tamping process.

Discrete Element Method Simulation of Railway Ballast Compactness During Tamping Process

Railway ballast tamping operation is employed in order to restore the geometry of railway track distorted by train traffics. In this paper, based on analysis of tamping principle, the discrete element analysis model of railway ballast is created using the discrete element method, numerical simulations are performed to study the change of railway ballast compactness during tamping process. This paper presents the motion trend of stone ballasts as the change trend of railway ballast compactness in qualitative analysis, and the distance between stone ballast and sleeper as the change index of railway ballast compactness in quantitative analysis. By comparing simulation data of different vibration frequencies, an optimal vibration frequency is obtained. The simulation results accord with the actual industrial tamping operation, which verifies that the discrete element method is an effective method to evaluate the change of railway ballast compactness during tamping process.

Experimental and Numerical Study of Railway Ballast Compactness during Tamping Process

Railway ballast tamping operations is employed in order to restore the geometry of railway track distorted by train traffics. The main goal is to compact the stone ballast under the sleepers supporting the railway squeezing and vibrations. The ballast compactness is the most direct index for evaluating the effect of tamping operation. This paper presents an experimental method used to detect the railway ballast compactness before and after tamping operation based on water-filling method, and creates a discrete element analysis model of railway ballast which analyzes the change of ballast compactness before and after tamping operation based on discrete element method. The simulation results are very similar with experimental results, which verify that the discrete element method is an effective method to evaluate the change of railway ballast compactness during tamping process.

Discrete Element Method Simulation of Mesomechanics of Railway Ballast during Tamping Process

Railway ballast tamping operations is employed in order to restore the geometry of railway track distorted by train traffics. The selection of tamping parameter is usually dependent on field trials and practical experience, for lack of theoretical basis. This paper creates discrete element analysis model of railway ballast using the discrete element method, the numerical simulations are carried out to study the mesomechanics of railway ballast during tamping process. We focus on the change of railway ballast compactness and stone ballast interaction force during tamping process. The present study can be helpful for the analysis of the internal mechanism of ballast compaction during tamping process.

A new discrete element analysis method for predicting hip joint contact stresses

Quantifying cartilage contact stress is paramount to understanding hip osteoarthritis. Discrete element analysis (DEA) is a computationally efficient method to estimate cartilage contact stresses. Previous applications of DEA have underestimated cartilage stresses and yielded unrealistic contact patterns because they assumed constant cartilage thickness and/or concentric joint geometry. The study objectives were to: (1) develop a DEA model of the hip joint with subject-specific bone and cartilage geometry, (2) validate the DEA model by comparing DEA predictions to those of a validated finite element analysis (FEA) model, and (3) verify both the DEA and FEA models with a linear-elastic boundary value problem. Springs representing cartilage in the DEA model were given lengths equivalent to the sum of acetabular and femoral cartilage thickness and gap distance in the FEA model. Material properties and boundary/loading conditions were equivalent. Walking, descending, and ascending stairs were simulated. Solution times for DEA and FEA models were ∼7s and ∼65min, respectively. Irregular, complex contact patterns predicted by DEA were in excellent agreement with FEA. DEA contact areas were 7.5%, 9.7% and 3.7% less than FEA for walking, descending stairs, and ascending stairs, respectively. DEA models predicted higher peak contact stresses (9.8–13.6MPa) and average contact stresses (3.0–3.7MPa) than FEA (6.2–9.8 and 2.0–2.5MPa, respectively). DEA overestimated stresses due to the absence of the Poisson's effect and a direct contact interface between cartilage layers. Nevertheless, DEA predicted realistic contact patterns when subject-specific bone geometry and cartilage thickness were used. This DEA method may have application as an alternative to FEA for pre-operative planning of joint-preserving surgery such as acetabular reorientation during peri-acetabular osteotomy.

DEM Simulation of Working Speed of Spade Soil Opener Influencing on the Dynamic Behavior of the Soil

To research spade soil opener work performance, based on two-dimensional discrete element method, using the secondary development of CAD technology, by soil opener CAD model to construct a two-dimensional discrete element analysis model soil opener using MFC programming techniques developed two dimensional discrete element simulation system based on building a soil discrete element calculation model of the soil opener process simulation, presented on a computer spade affect the dynamic behavior of the soil, has been the destruction of soil flow deformation achieve spade Soil computer-aided design, provides a new method for the analysis into the performance of the opener, and provide a reference for the design of the cut soil components.