scholarly journals CFD Investigation of Bath Flow and Its Related Alumina Transmission in Aluminum Reduction Cells: Slotted Anodes and Busbar Designs

Metals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 805
Author(s):  
Jiaming Zhu ◽  
Jie Li ◽  
Hongliang Zhang
Keyword(s):  
Horizontal Plane ◽  
Maximum Velocity ◽  
Aluminum Electrolysis ◽  
Raw Material ◽  
Stable Operation ◽  
Alumina Concentration ◽  
Half Cell ◽  
Aluminum Reduction ◽  
Computational Fluid Dynamics Cfd ◽  
Reduce Energy Consumption

Alumina is an indispensable raw material for the modern aluminum electrolysis industry. The distribution and transmission of alumina within the bath is of great significance to maintain stable operation and reduce energy consumption. In this study, a computational fluid dynamics (CFD) model was developed to investigate the bath flow and its related alumina transmission in aluminum reduction cells. The bath flow driven by bubbles, electromagnetic force, and aluminum flow presented two different sized vortices in the horizontal plane of the anode–cathode distance (ACD). Both numerical results and industrial data show that the average alumina concentration in the half-cell at the duct end is slightly larger than that of the tap end. With the application of slotted anodes, the maximum velocity of the bath flow increased and the average velocity decreased slightly in the horizontal plane, resulting in a more uniform distribution of alumina than that in the use of unslotted anodes. The symmetrical nature of the bath flow vortices became more obvious with the upgrade of the busbar design and the alumina concentration gradient became smaller within the bath.

scholarly journals Potassium Balance and Its Distribution in Commercial Aluminum Reduction Cells—When Potassium-containing Alumina Is Used as the Raw Material for Aluminum Electrolysis

2020 ◽  
Vol 88 (6) ◽  
pp. 574-579
Author(s):  
Youjian YANG ◽  
Xianwei HU ◽  
Zhaowen WANG ◽  
Andrey YASINSKIY ◽  
Peter POLYAKOV ◽  
...  
Keyword(s):  
Aluminum Electrolysis ◽  
Raw Material ◽  
Aluminum Reduction ◽  
Potassium Balance

scholarly journals OPTIMIZING THE VELOCITY OF RING SHAPE PARAMETER FOR DESIGNING THE NOZZLES USING CFD

2021 ◽  
pp. 1-10
Author(s):  
Obai Younis ◽  
Reem Ahmed ◽  
Ali Mohammed Hamdan ◽  
Dania Ahmed
Keyword(s):  
Shape Parameter ◽  
Maximum Velocity ◽  
Simulation Software ◽  
Governing Equations ◽  
Ansys Fluent ◽  
Ring Shape ◽  
Ring Location ◽  
Computational Fluid Dynamics Cfd ◽  
Triangular Elements ◽  
Volume Method

This study aims to optimize the velocity of ring shape parameter for designing the nozzles using computational fluid dynamics (CFD) and investigated the flow in nozzles using ANSYS, Inc. simulation software. The model geometries were defined using ANSYS FLUENT-Design Modeler platform. All nozzles were designed on unstructured triangular elements comprising of 1200000 mesh nodes. The differential governing equations were applied in ANSYS FLUENT based on a finite volume method. The distance and dimensions of ring location significantly influence the velocity of water during flow where the maximum velocity at double rings reduces the surface area at distance of 7mm and 15mm and 2x2 mm dimensions. Considering 8, 10, and 12 bar liner proportions, there was an increase in the velocity at maximum points in ring shapes.

Computer Analysis of S822 Aerofoil Section for Blades of Small Wind Turbines at Low Wind Speed

2017 ◽  
Vol 139 (5) ◽  
Author(s):  
Prachi R. Prabhukhot ◽  
Aditya R. Prabhukhot
Keyword(s):  
Wind Speed ◽  
Wind Turbine ◽  
Cfd Simulation ◽  
Maximum Velocity ◽  
Small Scale ◽  
Blade Profile ◽  
Ansys Fluent ◽  
Low Wind Speed ◽  
Upward Direction ◽  
Computational Fluid Dynamics Cfd

The power generated in wind turbine depends on wind speed and parameters of blade geometry like aerofoil shape, blade radius, chord length, pitch angle, solidity, etc. Aerofoil selection is the crucial factor in establishing the efficient wind turbine. More than one aerofoil in a blade can increase the efficiency further. Previous studies of different aerofoils have shown that efficiency of small scale wind turbine increases when NREL S822 aerofoil is used for wind speed on and above 10 m/s. This paper introduces a study on effect of low wind speed (V = 5 m/s) on performance of blade profile. Aerofoils NREL S822/S823 are used for microwind turbine with S823 near root and S822 near tip. Blade of 3 m radius with spherical tubercles over entire span is analyzed considering 5 deg angle of attack. The computational fluid dynamics (CFD) simulation was carried out using ANSYS fluent to study the behavior of blade profile at various contours. The study shows that blade experiences maximum turbulence and minimum pressure near trailing edge of the tip of blade. The region also experiences maximum velocity of the flow. These factors result in pushing the aerofoil in upward direction for starting the wind turbine to rotate at the speed as low as 5 m/s.

Research of Aluminum Reduction Cell Thermal Balanced Intelligent Control System

2011 ◽  
Vol 311-313 ◽  
pp. 644-647
Author(s):  
Xiang Yang Xia ◽  
Jie Li
Keyword(s):  
Control System ◽  
Heat Balance ◽  
Concentration Field ◽  
Flow Distribution ◽  
Aluminum Electrolysis ◽  
Primary Aluminum ◽  
Aluminum Reduction Cell ◽  
Control Technique ◽  
Aluminum Reduction ◽  
Reduction Cell

This paper proposes an intelligence control system of heat balance for aluminum reduction cell and reviews in each period the control technique of aluminum electrolysis at home and abroad. Mutual coupled relations of physical fields such as electric field, magnetic field, flow distribution, thermal field, stress field, concentration field in aluminum reduction cell are analyzed simply. In this system automatic control of furnace temperature and liquidus temperature in aluminum electrolyte are detected in real-time accurately. This control system can reduce the superheat of aluminum reduction cell in a certain range, and reduce production cost of per ton of primary aluminum on maximal degree. Thus, energy consumption and waste is decreased and heat balance in aluminum electrolysis is realized, efficient operations are certified in the product of aluminum electrolysis.

Effects of Fluid Viscosity and Impingement Angle on Submerged Jet Flowfields

2018 ◽  
Author(s):  
Soroor Karimi ◽  
Matthew Fulton ◽  
Siamack A. Shirazi ◽  
Brenton McLaury
Keyword(s):  
Maximum Velocity ◽  
Jet Impingement ◽  
Reynolds Numbers ◽  
Fluid Viscosity ◽  
Impingement Angle ◽  
Submerged Jet ◽  
Glass Spheres ◽  
Image Velocimetry ◽  
Computational Fluid Dynamics Cfd ◽  
Flow Experiments

Many researchers have utilized submerged jet impingement geometry to study solid particle erosion/corrosion. However, only a few studies have investigated changing impingement angle and fluid viscosity. In this study, Particle Image Velocimetry (PIV) experiments were conducted using 14 micron glass spheres for direct impingement geometry at viscosities of 1, 14, and 55 cP. These viscosities correspond to Reynolds numbers of approximately 57000, 4000, and 1000, respectively. It was observed that by increasing the viscosity the flow exiting the nozzle transitioned from extremely turbulent to laminar flow. The data indicated fully turbulent flow at the outlet for viscosities of 1 and 14 cP. In the case of 55 cP flow, the flow exiting the nozzle became laminar contributing to a higher maximum velocity in 55 cP flow. Experiments at these viscosities were also conducted at impingement angles of 90, 75, and 45 degrees to investigate the effects of the impinging jet angle on a flat plate. Additionally, a series of Computational Fluid Dynamics (CFD) simulations of the flowfield were performed to compare with the experimental data collected in this paper.

scholarly journals CFD Simulation of Airflow Dynamics During Cough Based on CT-Scanned Respiratory Airway Geometries

Symmetry ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 595 ◽  
Author(s):  
Guiyue Kou ◽  
Xinghu Li ◽  
Yan Wang ◽  
Mouyou Lin ◽  
Yuping Zeng ◽  
...  
Keyword(s):  
Flow Rate ◽  
Cfd Simulation ◽  
Peak Flow ◽  
Maximum Velocity ◽  
Flow Distribution ◽  
Peak Flow Rate ◽  
Respiratory Airway ◽  
Computational Fluid Dynamics Cfd ◽  
Left And Right ◽  
Cfd Method

The airflow dynamics observed during a cough process in a CT-scanned respiratory airway model were numerically analyzed using the computational fluid dynamics (CFD) method. The model and methodology were validated by a comparison with published experimental results. The influence of the cough peak flow rate on airflow dynamics and flow distribution was studied. The maximum velocity, wall pressure, and wall shear stress increased linearly as the cough peak flow increased. However, the cough peak flow rate had little influence on the flow distribution of the left and right main bronchi during the cough process. This article focuses on the mathematical and numerical modelling for human cough process in bioengineering.

scholarly journals Influence of Current Density on the Microstructure of Carbon-Based Cathode Materials during Aluminum Electrolysis

2020 ◽  
Vol 10 (7) ◽  
pp. 2228
Author(s):  
Wei Wang ◽  
Kai Sun
Keyword(s):  
Current Density ◽  
Aluminum Electrolysis ◽  
Cathode Current Density ◽  
Cathodic Current Density ◽  
Cathodic Current ◽  
Aluminum Reduction ◽  
Electrostatic Charging ◽  
Cathode Current ◽  
Current Densities ◽  
Sodium Expansion

Sodium expansion plays an important role in cathode deterioration during aluminum electrolysis. In this work, the sodium expansion of semigraphitic cathode material has been measured at various cathodic current densities using a modified Rapoport apparatus. We have studied the microstructural changes of carbon cathodes after aluminum electrolysis using high-resolution transmission electron microscopy (HRTEM). Because of an increasing trend toward higher amperage in retrofitted aluminum reduction cells, an investigation is conducted both at a representative cathode current density (0.45 A/cm2) and at a high cathodic current density (0.7 A/cm2). The results indicate that the microstructures of carbon cathodes can be modified by Joule heating and electrostatic charging with higher current densities during aluminum electrolysis. With the penetration of the sodium and melt, zigzag and armchair edges, disordered carbon, and exfoliation of the surface layers may appear in the interior of the carbon cathode. The penetration of the sodium and melt causes remarkable stresses and strains in the carbon cathodes, that gradually result in performance degradation. This shows that increasing the amperage in aluminum reduction cells may exacerbate the material deterioration of the cathodes.

Sign in / Sign up

Export Citation Format

Share Document