Flow behavior of powder particles in layering process of selective laser melting: Numerical modeling and experimental verification based on discrete element method

Purpose The dryer feed chute of the pellet plant plays an important role in the pelletizing process. The chute discharges sticky and moist iron ore fines (<1 mm) to the inline rotary dryer for further processing. Since the inception of the installation of the dryer feed chute, the poor flowability of the feed materials has caused severe problems such as blockages and excessive wear of chute liners. This leads to high maintenance costs and reduced lifetime of the liner materials. Constant housekeeping is needed for maintaining the chute and reliable operation. The purpose of this study is to redesign the dryer feed chute to overcome the above challenges. Design/methodology/approach The discrete element method (DEM) has been used to model the flow of cohesive materials through the transfer chute. Physical experiments have been performed to understand the most severe flow conditions. A DEM material model is also developed for replicating the worst-case material condition. After identifying the key problem areas, concept designs were proposed and simulated to assess the design improvements to increase the reliability of chute operation. Findings Flow simulations correlated well with the existing flow behavior of the iron ore fines inside the chute. The location of the problematic areas has been validated with that of the previously installed chute. Subsequently, design modifications have been proposed. This includes modification of deflector plate and change in slope and cross-section of the chute. DEM simulations and analysis were conducted after incorporating these design changes. A comparison in the average velocity of particle and force on chute wall shows a significant improvement using the proposed design. Originality/value Method to calibrate DEM material model was found to provide accurate prediction and modeling of the flow behavior of bulk material through the real transfer chute. DEM provided greater insight into the performance of the chute especially modeling cohesive materials. DEM is a valuable design tool to assist chute designers troubleshoot and verify chute designs. DEM provides a greater ability to model and assess chute wear. This technique can help in achieving a scientific understanding of the flow properties of bulk solids through transfer chute, hence eliminate challenges, ensuring reliable, uninterrupted and profitable plant operation. This paper strongly advocates the use of calibrated DEM methodology in designing bulk material handling equipment.

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Numerical modeling of debris flow kinematics using discrete element method combined with GIS

Landslides and Engineered Slopes. From the Past to the Future ◽

10.1201/9780203885284-c95 ◽

2008 ◽

pp. 769-775 ◽

Cited By ~ 1

Author(s):

Hengxing Lan ◽

C Martin ◽

C Zhou

Keyword(s):

Numerical Modeling ◽

Debris Flow ◽

Discrete Element Method ◽

Discrete Element ◽

Element Method

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Numerical Modeling of a Punch Penetration Test Using the Discrete Element Method

Slovak Journal of Civil Engineering ◽

10.2478/sjce-2020-0008 ◽

2020 ◽

Vol 28 (2) ◽

pp. 1-7

Author(s):

Rouhollah Basirat ◽

Jafar Khademi Hamidi

Keyword(s):

Numerical Modeling ◽

Discrete Element Method ◽

Numerical Models ◽

Confining Pressure ◽

Discrete Element ◽

Numerical Results ◽

Strength Parameter ◽

Penetration Test ◽

Strength Parameters ◽

Element Method

AbstractUnderstanding the brittleness of rock has a crucial importance in rock engineering applications such as the mechanical excavation of rock. In this study, numerical modeling of a punch penetration test is performed using the Discrete Element Method (DEM). The Peak Strength Index (PSI) as a function of the brittleness index was calculated using the axial load and a penetration graph obtained from numerical models. In the first step, the numerical model was verified by experimental results. The results obtained from the numerical modeling showed a good agreement with those obtained from the experimental tests. The propagation path was also simulated using Voronoi meshing. The fracture was created under the indenter in the first step, and then radial fractures were propagated. The effects of confining pressure and strength parameters on the PSI were subsequently investigated. The numerical results showed that the PSI increases with enhancing the confining pressure and the strength parameter of the rock, including cohesion and the friction angle. A new relationship between the strength parameters and PSI was also introduced based on two variable regressions of the numerical results.

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