Numerical Modeling of Wall Pressure in Silo with and Without Insert

AbstractThis paper presents a methodology based on the finite element method to simulate the flow of granular materials. Moreover, it allows proper estimation of dynamic pressure during silo discharge since this subject is still under discussion, especially for designing silos with an insert (an input element). A 2-D simulation of the discharge process of a cylindrical silo with cone and a central discharging orifice was performed. Two cases were studied, with and without using insert in silo. Numerical analysis was carried out with the help of the uncoupled arbitrary Lagrangian–Eulerian (ALE) approach. The resulting dynamic pressure distribution on the silo wall for each of the two cases was inferred numerically. The resulting values of pressure were compared with the results of the experimental study on a cylindrical metal silo to demonstrate the accuracy of the numerical model in determining the dynamic wall pressure, especially in the case of using an insert in silo during discharge.

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Analysis of Spiral-Grooved Gas Journal Bearings by the Narrow-Groove Theory and the Finite Element Method At Large Eccentricities

Journal of Tribology ◽

10.1115/1.4045636 ◽

2020 ◽

Vol 142 (4) ◽

Cited By ~ 1

Author(s):

Elia Iseli ◽

Eliott Guenat ◽

Roger Tresch ◽

Jürg Schiffmann

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Dynamic Pressure ◽

Journal Bearings ◽

The Finite Element Method ◽

Pressure Profiles ◽

Stability Maps ◽

Time Periodic ◽

Good Agreement ◽

Element Method

Abstract A finite groove approach (FGA), based on the finite element method (FEM), is used for analyzing the static and dynamic behavior of spiral-grooved aerodynamic journal bearings at different eccentricities, number of grooves, and compressibility numbers. The results of the FGA are compared with the narrow-groove theory (NGT) solutions. For the rotating-groove case, a novel time-periodic solution method is presented for computing the quasi-steady-state and dynamic pressure profiles. The new method offers the advantage of avoiding time-consuming transient integration, while resolving a finite number of grooves. The static and dynamic solutions of the NGT and FGA approach are compared, and they show good agreement, even at large eccentricities (ε=0.8) and high compressibility numbers (Λ = 40). Stability maps at different eccentricities are presented. At certain operation points, a stability decrease toward larger eccentricities is observed. The largest stability deviations of the NGT from the FGA solutions occur at large groove angle, low number of grooves, and large compressibility numbers.

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Research on Numerical Simulation of Dynamic Pressure for Stress Sensibility Coal Seam

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.2293 ◽

2011 ◽

Vol 383-390 ◽

pp. 2293-2299

Author(s):

Yun Hong Ding ◽

Bao Hui Wang ◽

Xiang Zhen Yan

Keyword(s):

Numerical Simulation ◽

Finite Element Method ◽

History Matching ◽

Dynamic Pressure ◽

Ordos Basin ◽

Coupling Model ◽

The Finite Element Method ◽

Coal Seams ◽

The Face ◽

Good Agreement

Based on the orthotropic physical properties of coal cleats, the fluid-solid coupling model for stress sensibility coal seams is established. The equations of the coupling model are solved by using the finite element method. The history matching for JS-3 well in Ordos basin is carried on by using the coupling model. The comparison between calculated results based on the coupling model and the measured values indicates their good agreement, which verifies the accuracy and rationality of the model. The effect of the permeability orthotropic coefficient of coal cleats on the pressure distribution in coal seams is analyzed. The results show that the pressure along the butt cleats direction increases with permeability orthotropic coefficient increasing; The pressure along the face cleats decreases with permeability orthotropic coefficient increasing between 0m~30m and 170m~200m, whereas both increases from 30m to 170m.

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Thermal Analysis on Symmetric Rectangular Stackable Supercapacitors

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1092-1093.539 ◽

2015 ◽

Vol 1092-1093 ◽

pp. 539-542 ◽

Cited By ~ 1

Author(s):

Mei Na Zheng ◽

Yan Song Li ◽

Jun Liu

Keyword(s):

Finite Element Method ◽

Thermal Management ◽

Thermal Model ◽

Management Systems ◽

Maximum Temperature ◽

Discharge Process ◽

The Finite Element Method ◽

Applied Current ◽

Cooling Systems ◽

Simulation Results

In this paper, thermal model of the symmetric rectangular stackable supercapacitors are established. By using the finite element method, the temperature distribution of the supercapacitor is simulated. Then the supercapacitor's thermal behavior under the ambient temperature, but with different current density is analyzed. The simulation results show that the maximum temperature during the discharge process occurs in the center of the supercapacitor. The maximum temperature is associated with the applied current, and the higher the applied current is, the higher the maximum temperature is. It's necessary to control the maximum temperature within the allowable values, by establishing reasonable thermal management systems and cooling systems.

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Simulation of tuning graphene plasmonic behaviors by ferroelectric domains for self-driven infrared photodetector applications

Nanoscale ◽

10.1039/c9nr06508c ◽

2019 ◽

Vol 11 (43) ◽

pp. 20868-20875 ◽

Cited By ~ 1

Author(s):

Junxiong Guo ◽

Yu Liu ◽

Yuan Lin ◽

Yu Tian ◽

Jinxing Zhang ◽

...

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Interfacial Effect ◽

Infrared Photodetector ◽

The Finite Element Method ◽

Ferroelectric Domains ◽

Element Method

We propose a graphene plasmonic infrared photodetector tuned by ferroelectric domains and investigate the interfacial effect using the finite element method.

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