Utilization of fused deposition method 3D printing for evaluation of discrete element method simulations

FDM 3D printing is used for designing prototype assessment in engineering production. It is usually used to verify the functionality of kinematics mechanisms. It can also be used for innovation in agricultural production, eg. the development of new mechanisms for agriculture tools. Such a mechanism as well as the entire components is printed using FDM and they are made of plastics. This whole can be experimentally verified in a laboratory trough. The article deals with the verification of the possibilities of using FDM technology for the design of agricultural tools. The material properties, namely stress-strain, of the plastics after printing are entered into the Ansys mechanical library, and the DEM results are also imported into Ansys mechanical. Material properties of plastics for FDM technology such as PLA, PETG show that its mechanical properties limited their using for validation

Using the FEM model for design the heat treatment of an agricultural tools

ArticleAgricultural tools need mechanical properties such as abrasive wear, hardness and toughness. These mechanical properties are achieved by choosing a suitable steel and subsequent heat treatment of the steel. Phases of the microstructure affects the final steel properties. The phase composition in the steel is influenced with the designing of the heat treatment. 25C rMo4 steel was investigated for the production of agricultural tools. The heat treatments ware designed for different cooling conditions. The salt bath was used to cooling as a medium with subsequent cooling on the water or in the air. The FEM method was u sed to designing the heat treatment conditions. The Johnson - Mehl - Avrami - Kolmogorov equation and the Koistinen - Marburger equations were used to prediction the microstructure phases. The microstructures were verified with experimental measurements. The ASTM G65 method was using for abrasion resistance tests. The results show that this procedure can be used to designing parameters of heat treatment of agricultural tools

Methodology of the stress detemination in the tool module during the work of the agriculture machine

ArticleMachine construction is designed using by mathematical models. The frame is a fundamental part of an agricultural soil cultivation machine so that forces were transfered during transport and machine work to frame. The stress in the machine frame is important to know for the best frame design of the machine. The mathematical model included measued strain can able to design or detect deficiencies on the machine frame. Due to the transfer of forces from the tools, stress is created in the machine frame. High requirements are placed on the determination of boundary conditions for mathematical models in agricultural machinery. Various types, sizes and equipment of agricultural tools significantly affect the transfer of draught force to the machine. The direction and magnitude of the forces, that are caused by agricultural tools, it is important to find out. Ansys mechanical solver have been used to determination strain like response of frame from chisel module. The results can be used as a boundary condition for mathematical models

DEM modelling of tillage tools in sand and verification of draft forces in the soil box

Received: April 28th, 2021 ; Accepted: September 29th, 2021 ; Published: October 25th, 2021 ; Correspondence: [email protected] resistance is still being important parameter during tillage. By reducing the soil resistance during processing, greater efficiency and cost reduction can be achieved. With the correct design of the shape of the tillage tools, reduction in the force required for tillage can be achieved. New tool designs must be tested in field conditions to determine the effect. Using DEM (Discrete element method) modelling, individual designs can be compared without the need for field tests. However, the accuracy of the model must first be verified on real tests. The paper deals with the creation of a mathematical model of sand, which is used for testing tillage tools in the soil box. The models are focused on tests of various shapes of wings on tillage tools. Draft forces are compared, and the correctness of the model is verified

Discrete element simulation of rapeseed shear test

ArticleSuiTable equipment are required for storage and transportation of rapeseed which are developed according to rules for bulk matters. It is one of reasons where bulk matter properties are important to the design. Bulk matter properties are important to known as angle of repose, internal friction, external friction, adhesivity force and other bulk properties. Experimental values of bulk properties are added to mathematical models. The model should be calibrated with adequate experiment. The shear test is one of popular calibration test for bulk matters so that be able done experiment and numerical model in one. The aim of this paper is simulation of rapeseed bulk properties during shear strain and flow and its evaluation and calibration with experimental tests. RockyDEM software was used for numerical simulation of rapeseed. Shear test, angle of repose, static and dynamic friction test were used to calibration of the numerical rapeseed model. Sensitivity of numerical model is discussed on the bulk properties

A study on wear failure analysis of tungsten carbide hardfacing on carbon steel blade in a digester tank

This paper addresses wear failure analysis of tungsten carbide (WC) hardfacing on a carbon steel blade known as the continuous digester blade (CD blade). The CD blade was placed in a digester tank to mix ilmenite ore with sulphuric acid as part of a production process. Tungsten carbide hardfacing was applied on the CD blade to improve its wear resistance while the CD blade was exposed to an abrasive and acidic environment. Failure analysis was car-ried out on the hardfaced CD blade in order to improve its wear resistance and lifetime. A thickness and hardness comparison study was conducted on worn and unworn specimens from the CD blades. The carbide distribution along with elemental composition analysis of the hardfaced CD blade specimens was examined using scanning electron microscopy and energy-dispersive spectroscopy. The investigation revealed that an inconsistent hardfacing thickness was welded around the CD blade. Minimum coating thickness was found at the edges of the blade surfaces causing failure to the blades as the bare carbon steel blades were exposed to the mixed environment. The wear resistance of the CD blade can be improved by distributing the carbide uniformly on the hardfaced coating. Applying extra coating coverage at the critical edge will prevent the exposure of bare carbon steel blade, thus increasing the CD blade lifetime

Tracing of the rapeseed movement by using the contrast point tracking method for DEM model verification

Received: May 30th, 2022 ; Accepted: August 1st, 2022 ; Published: August 4th, 2022 ; Correspondence: [email protected] designing the efficient storage and transport of rapeseed, it is necessary to follow the rules of bulk material, know its properties, and use appropriate equipment. The mentioned properties of bulk material are essential for simulating the numerical model and obtaining the parameters of the geometry particle tracing during the rapeseed manipulation. In order to determine the angle of repose and mechanical properties of rapeseed, the results of previous experiments were used. The aim of this paper was to propose the methodology for calculating the traces of individual particles using the contrast point method during a real test to calibrate and verify a numerical model of the same system as in a real test. RockyDEM software was used to create the numerical model of rapeseed. The numerical model was used to test the flow analysis of rapeseed particles. The experiment measuring rapeseed particle traces was performed using an assembled experimental device. The rapeseed particles and the contrast point particles were poured out from the device, and a camera recorded the process. In parallel with the real experiment, the angle of repose test was performed on the same device to verify the numerical model. The results showed that the methodology is suitable for the DEM model verification with an accuracy of 3.77 mm in the X-axis, 0.55 mm in the Y-axis and 1.7 mm in the Z-axis. This confirmed that the proposed method is suitable for determining the surface behaviour of bulk material to verify the DEM model