CFD modeling of erosion wear in pipe bend for the flow of bottom ash suspension

Erosive wear caused by particulates slurry is one of the major concerns in the pipe bend which may results in the failure of the pipe flow system. In the present work, erosion wear rate through mitre pipe bend caused by silica sand particulates slurry has been investigated using ANSYS Fluent code. The solid spherical particulates of size 125 µm and 250 µm having density of 2650 Kg/m3, were tracked to compute the erosion wear rate using Discrete Phase Method (DPM) model. The particulates were tracked using Eulerian-Lagrange approach along with k-ɛ turbulent model for continuous fluid phase. The silica particulates were injected at solid concentration of 5% and 10% (by weight) from the pipe inlet surface for wide range of velocities viz. 1–8 ms−1. The erosion wear rate was computed through four computational erosion models viz. Generic, Oka, Finnie and Mclaury. Furthermore, the outcomes obtained through Generic models are verified through existing experimental data in the literture. Moreover, the results of DPM concentration, turbulence intensity and particle tracking were predicted to analyze the secondary flow behaviour through the bend cross section. Finally, the effect of particulate size, solid concentration and flow velocity were discussed on erosion wear rate through bend cross section. The findings show that the locality of maximum erosive wear is positioned at the extrados of the bend outlet cross section. Additionally, it is found that Mclaury model offers higher erosion rate as compared to the other models and provides benchmark for designing the slurry pipeline system.

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Computational analysis of solid particle-erosion produced by bottom ash slurry in 90° elbow

MATEC Web of Conferences ◽

10.1051/matecconf/201925204008 ◽

2019 ◽

Vol 252 ◽

pp. 04008

Author(s):

Jashanpreet Singh ◽

Jatinder Pal Singh ◽

Mandeep Singh ◽

Miroslaw Szala

Keyword(s):

Bottom Ash ◽

Outer Wall ◽

Wall Region ◽

Erosion Wear ◽

Slurry Erosion ◽

Low Velocity ◽

Drag Forces ◽

Shape Pattern ◽

Discrete Phase ◽

Computational Fluid Dynamics Cfd

Present work is devoted to investigation of the slurry erosion wear in a 90° elbow by using commercial Computational fluid dynamics (CFD) code FLUENT. Discrete phase erosion wear model was used to predict erosion in 90° elbow by solving the governing equations through Euler-Lagrange scheme. Particle tracking was considered by using standard k-ε turbulence scheme for the flow of bottom ash slurry. Erosion wear in elbow was investigated along with velocity distribution and turbulence intensity. The radius-to-diameter (r/D) ratio was taken as 1.5. Results show that erosion rate increases with increase in velocity. Present numerical simulation model holds close agreement with previous studies. Distorted patterns appeared at low velocities. The V-shape pattern appeared on the outer wall of elbow at high velocities. The low velocity region occurs around circumference of elbow wall at outer wall of elbow due to stimulation of the drag forces near the wall region.

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Study on role of particle shape in erosion wear of austenitic steel using image processing analysis technique

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/1350650118794698 ◽

2018 ◽

Vol 233 (5) ◽

pp. 712-725 ◽

Cited By ~ 5

Author(s):

Jashanpreet Singh ◽

Satish Kumar ◽

SK Mohapatra

Keyword(s):

Fly Ash ◽

Austenitic Steel ◽

Bottom Ash ◽

Three Dimensional ◽

Underlying Mechanism ◽

Solid Particles ◽

Erosion Wear ◽

Sand Surface ◽

Tailings Sand ◽

Slurry Pot Tester

Properties of flowing media (e.g. such as fly ash, bottom ash, coal, mineral tailings, sand slurries, etc.) play a crucial role in the service life of centrifugal slurry pump components. Generally, these solid particles vary in shape and size. In literature, a limited number of studies have been carried out to investigate the influence of particle size and shape on erosion wear. Stainless steel (SS 316L) is the most commonly used material for the fabrication of slurry pump components namely, casing, impeller, shafts, and sealing columns. In the present study, the influence of particle type and circularity factor on erosion wear of austenitic steel has been studied. A slurry pot tester (Ducom TR-41) was used to perform the experiments that established the erosion wear of slurry pump austenitic steel under the influence of the parameters noted above. Abrasives used in the current study are fly ash, bottom ash, and sand. Surface smoothness, circularity factor, coefficient of variance, sphericity, and solidity of solid particles were also analyzed prior to performing the experiments. The circularity factor value and erosion wear rate hold a power law relationship. Three-dimensional surface plots were plotted to explain the underlying mechanism of erosion wear.

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The Study of Slurry Erosion Wear Behaviour of Coal Bottom Ash Slurry Handling Pipeline

TMS 2019 148th Annual Meeting & Exhibition Supplemental Proceedings - The Minerals, Metals & Materials Series ◽

10.1007/978-3-030-05861-6_68 ◽

2019 ◽

pp. 697-710 ◽

Cited By ~ 1

Author(s):

Satish R. More ◽

Sudeep P. Ingole ◽

Dhananjay V. Bhatt ◽

Jyoti V. Menghani

Keyword(s):

Bottom Ash ◽

Wear Behaviour ◽

Erosion Wear ◽

Slurry Erosion ◽

Coal Bottom Ash

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Design Optimization of a Helical Coil Gas Cooler Based on the Results of CFD Modeling of Erosion Wear

Journal of Physics Conference Series ◽

10.1088/1742-6596/2150/1/012017 ◽

2022 ◽

Vol 2150 (1) ◽

pp. 012017

Author(s):

V A Mikula ◽

G E Maslennikov ◽

T F Bogatova

Keyword(s):

Design Optimization ◽

Maximum Level ◽

Impact Angle ◽

Flow Path ◽

Combined Cycle ◽

Cfd Modeling ◽

Helical Coil ◽

Baffle Plate ◽

Erosion Wear ◽

Structural Element

Abstract Simulation of erosion wear and design optimization have been performed for a convective gas cooler with a helical coil. Based on the results of simulation of the standard gas cooler design with a flat baffle used in Shell gasification-based combined cycle unit, it is concluded that the particle impact angle is the main factor determining the erosion maximum. To reduce erosion, it is necessary to install a structural element instead of the flat baffle to align the flow path of ash particles at the inlet to the gas cooler. The results of simulation for various baffle shapes show that a hemispherical baffle is optimal. The use of a hemispherical baffle plate made it possible to align the ash particle flow path at the inlet to the gas cooler channels and reduce the maximum level of erosion by a factor of almost 4 compared to the standard geometry of the baffle plate.

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3D CFD Modeling and Experimental Validation for Slurry Flow Through Pipe Bend

Volume 4: Fatigue and Fracture; Fluids Engineering; Heat Transfer; Mechatronics; Micro and Nano Technology; Optical Engineering; Robotics; Systems Engineering; Industrial Applications ◽

10.1115/esda2008-59087 ◽

2008 ◽

Author(s):

Arvind Kumar ◽

D. R. Kaushal ◽

Umesh Kumar

Keyword(s):

Experimental Data ◽

Pressure Drop ◽

Flow Velocity ◽

Cfd Modeling ◽

Pipeline System ◽

Detailed Knowledge ◽

Eulerian Model ◽

Pipe Bend ◽

Horizontal Pipe ◽

Test Loop

Bends are integral part of any slurry pipeline system and are prone to excessive wear. Therefore, a detailed knowledge of the flow characteristics in the bends will enable us to identify the causes of excessive wear which in turn may help in developing remedial steps to control the excessive wear. In the present study, experimental data are collected in a 90 degree horizontal pipe bend having bend radius of 148 mm situated in a pilot plant test loop with pipe diameter of 53 mm. The experiments are performed at volumetric concentration of 16.28% of silica sand having mean particle diameter of 448.5 micron. The flow velocity was varied from 1.78 to 3.56 m/s. Separation chambers are provided at each pressure tap for interface separation of slurry and manometric fluid, water being the intermediate fluid. For better accuracy, pressure drop along the pipeline is measured by an inclined manometer. Electromagnetic flow meter is used for the measurement of slurry discharge. It is observed that pressure drop along the pipe bend increases with flow velocity. The experimental data collected in the present study have been compared with the three-dimensional computational fluid dynamics (CFD) modeling, using Eulerian two-phase model and commercial CFD package FLUENT 6.2. Eulerian model expands the definition of continuum assumption to the dispersed phase and treats both continuous and dispersed phases separately as two phases. Both phases are linked using the drag force in the momentum equation. The standard k-epsilon model is used to treat turbulence phenomena in both the phases. The granular theory for the liquid–solid flow of the Eulerian model is introduced. Gambit software is used for the development of mesh. It is observed that CFD modeling gives fairly accurate results for almost all the pressure drop data considered in the present study. CFD modeling results for concentration and velocity profiles for collected experimental data have also been presented.

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CFD Modeling of Multi-Sized Particulate Slurry Flow through Pipe Bend

Journal of Applied Fluid Mechanics ◽

10.36884/jafm.13.04.31066 ◽

2020 ◽

Vol 13 (04) ◽

Keyword(s):

Cfd Modeling ◽

Slurry Flow ◽

Pipe Bend ◽

Flow Through

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INVESTIGATION OF THE INFLUENCE TWO-PHASE FLOWS PARAMETERS ON THE EROSION WEAR OF THE GAS PIPELINES BENDS

Municipal economy of cities ◽

10.33042/2522-1809-2020-1-154-240-247 ◽

2020 ◽

Vol 1 (154) ◽

pp. 240-248

Author(s):

Ya. Doroshenko

Keyword(s):

Flow Rate ◽

Gas Flow ◽

Particle Diameter ◽

Continuous Phase ◽

Gas Pipeline ◽

Cfd Modeling ◽

Erosion Wear ◽

Two Phase ◽

Software Complex ◽

Dispersed Particles

CFD modeling (Computational Fluid Dynamics) Lagrangian approach (model DPM (Discrete Phase Model)) in ANSYS Fluent R19.2 Academic software complex investigates the influence of twophase gas flow velocity, size and flow rate of dispersed particles on the location and magnitude of gas pipeline bends erosion wear. The motion of the continuous phase was modeled by the solution of the Navier-Stokes equation and the continuity of the closed two-parameter k-ε turbulence model with the corresponding initial and boundary conditions. The motion trajectories of the dispersed particles were determined by integrating the force equations acting on each particle. The erosion wear of gas pipeline bends was modeled using the Finney equation. The studies were performed for gas flow velocities at the inlet of the bend from 4 m/s to 19 m/s, the diameters of the dispersed particles 0.005 mm, 0.01 mm, 0.05 mm, 0.1 mm, 0.5 mm and 1.0 mm and the flow rate of the dispersed particles from 0.0002 kg/s to 0.0022 kg/s. Natural gas was selected as the continuous phase, and sand was dispersed. The geometry of each of the simulated taps and the pressure at the outlet of the bend were assumed to be the same. The simulation results were visualized in the postprocessor software complex by constructing erosion rate velocity fields on gas pipeline bends. From the visualized results it is determined that the largest influence on the location of the erosion wear of the pipeline bends has the diameter of the dispersed particles and the least concentration. The influence of the two-phase gas flow parameters on the location of the field of their maximum erosion wear is determined. The graphical dependences of the maximum velocity of erosion wear of gas pipeline bends on each of the studied parameters of the two-phase gas stream are constructed. It has been determined that the diameter of the dispersed particles and the velocity of the gas stream have the greatest influence on the erosion wear of the erosion of the bends. Keywords: bend, dispersed particle diameter, dispersed particle rate, dispersed phase, erosion wear, Finney equation, gas flow rate, Lagrange approach.

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