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

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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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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The Effect of Bench Arrangements on the Natural Ventilation of a Multispan Greenhouse

Volume 8A: Heat Transfer and Thermal Engineering ◽

10.1115/imece2013-63304 ◽

2013 ◽

Author(s):

Sunita Kruger ◽

Leon Pretorius

Keyword(s):

Fluid Dynamics ◽

Natural Ventilation ◽

Three Dimensional ◽

Two Dimensional ◽

Low Velocity ◽

Lower Velocity ◽

Cfd Models ◽

Temperature Distributions ◽

Computational Fluid Dynamics Cfd ◽

Plant Level

In this paper, the influence of various bench arrangements on the microclimate inside a two-span greenhouse is numerically investigated using three-dimensional Computational Fluid Dynamics (CFD) models. Longitudinal and peninsular arrangements are investigated for both leeward and windward opened roof ventilators. The velocity and temperature distributions at plant level (1m) were of particular interest. The research in this paper is an extension of two-dimensional work conducted previously [1]. Results indicate that bench layouts inside the greenhouse have a significant effect on the microclimate at plant level. It was found that vent opening direction (leeward or windward) influences the velocity and temperature distributions at plant level noticeably. Results also indicated that in general, the leeward facing greenhouses containing either type of bench arrangement exhibit a lower velocity distribution at plant level compared to windward facing greenhouses. The latter type of greenhouses has regions with relatively high velocities at plant level which could cause some concern. The scalar plots indicate that more stagnant areas of low velocity appear for the leeward facing greenhouses. The windward facing greenhouses also display more heterogeneity at plant level as far as temperature is concerned.

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Edge and particle embedment effects in low- and high-stress slurry erosion wear of steels and elastomers

Wear ◽

10.1016/j.wear.2017.06.004 ◽

2017 ◽

Vol 388-389 ◽

pp. 126-135 ◽

Cited By ~ 5

Author(s):

N. Ojala ◽

K. Valtonen ◽

J. Minkkinen ◽

V.-T. Kuokkala

Keyword(s):

High Stress ◽

Erosion Wear ◽

Slurry Erosion

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Experimental Study and Analysis of Slurry Erosion Wear of SS304L Material

IOSR Journal of Mechanical and Civil Engineering ◽

10.9790/1684-17010022934 ◽

2017 ◽

Vol 17 (01) ◽

pp. 29-34 ◽

Cited By ~ 1

Author(s):

K. M. Nilkar

Keyword(s):

Experimental Study ◽

Erosion Wear ◽

Slurry Erosion

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Impact of Turbulence Models on the Air Flow in a Confined Rectangular Space

Engineering Science & Technology ◽

10.37256/est.212021627 ◽

2020 ◽

pp. 46-53

Author(s):

Jakub Mularski ◽

Amit Arora ◽

Muhammad Azam Saeed ◽

Łukasz Niedźwiecki ◽

Samrand Saeidi

Keyword(s):

Experimental Data ◽

Air Flow ◽

Turbulence Models ◽

The Other ◽

Experimental Measurements ◽

Wall Region ◽

Sst Model ◽

Computational Fluid Dynamics Cfd ◽

The Impact ◽

The Given

The paper regards the impact of four different turbulence models on the air flow pattern in a confined rectangular space. The following approaches are analyzed. The Baseline (BSL) Reynolds model, the Speziale-Sarkar-Gatzki (SSG) Reynolds model, the Menter's shear-stress transport (SST) model and the basic k-ε model. Computational fluid dynamics (CFD) results are compared with the experimental measurements in four different planes. The Reynolds number for the given conditions is equal to 5000. The k-ε model yielded the most accurate results with regard to the experimental data but its reliability decreased near the wall region. With respect to the other models, it was also found that the k-ε approach generated the least circulating flow.

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Optimization of Velocity Flap Structures in High Sensitivity Macrofluidic Airflow Sensor

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i4.27.22428 ◽

2018 ◽

Vol 7 (4.27) ◽

pp. 11

Author(s):

Mohamad Dzulhelmy bin Amari ◽

Muhamad Saifuddin b. Abdull Shukor ◽

Sukarnur Che Abdullah

Keyword(s):

High Sensitivity ◽

Low Velocity Impact ◽

Low Velocity ◽

Velocity Impact ◽

Fast Detection ◽

Intelligent Control System ◽

Highly Sensitive ◽

Computational Fluid Dynamics Cfd ◽

Airflow Sensor ◽

Program Software

Automated reaction from the system is most important in fulfilling the requirement of the intelligent control system. Hence, many related studies regarding in developing the hardware of the system such as high sensitivity of the airflow sensor in detecting the changes either in user or the environment. The effect of the fast detection of the sensor through the high sensitivity of the airflow sensor have enable the system to identify and analyze the behavior of the user in higher accuracy compared to conventional system. Within the scope of airflow sensitivity, separation between two parts in the airflow sensor in altering the velocity impact have been inquired in purpose, while a few investigations in relations to determine the pressure contour of the main parts have been explored by application of using Computational Fluid Dynamics (CFD. This simulation is performed in the ANSYS program software. Thus, this study consequently intends to be focus on detection the high sensitivity of the airflow movement by distinguishing the high and low velocity impact. The optimization the airflow sensor in this study based on design parameter also done in order to design and develop a highly sensitive airflow sensor

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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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Modeling and Simulations of Deteriorated Turbulent Heat Transfer in Wall-Heated Cylindrical Tube

Journal of Verification Validation and Uncertainty Quantification ◽

10.1115/1.4045522 ◽

2019 ◽

Vol 4 (3) ◽

Author(s):

Prasad Vegendla ◽

Rui Hu

Keyword(s):

Heat Transfer ◽

Nuclear Power ◽

Three Dimensional ◽

Cylindrical Tube ◽

Fluid Flows ◽

Turbulent Heat Transfer ◽

Wall Region ◽

Turbulent Heat ◽

Modeling And Simulations ◽

Computational Fluid Dynamics Cfd

Abstract This paper discusses the modeling and simulations of deteriorated turbulent heat transfer (DTHT) for a wall-heated fluid flows, which can be observed in gas-cooled nuclear power reactors during pressurized conduction cooldown (PCC) event due to loss of force circulation flow. The DTHT regime is defined as the deterioration of normal turbulent heat transport due to increase of acceleration and buoyancy forces. The computational fluid dynamics (CFD) tools such as Nek5000 and STAR-CCM+ can help to analyze the DTHT phenomena in reactors for efficient thermal-fluid designs. Three-dimensional (3D) CFD nonisothermal modeling and simulations were performed in a wall-heated circular tube. The simulation results were validated with two different CFD tools, Nek5000 and STAR-CCM+, and validated with an experimental data. The predicted bulk temperatures were identical in both CFD tools, as expected. Good agreement between simulated results and measured data were obtained for wall temperatures along the tube axis using Nek5000. In STAR-CCM+, the under-predicted wall temperatures were mainly due to higher turbulence in the wall region. In STAR-CCM+, the predicted DTHT was over 48% at outlet when compared to inlet heat transfer values.

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The Design of Refinement Criteria for Dynamic Grid Adaptation Applied to Airfoil Flow Modeling

Emerging Technology in Fluids, Structures, and Fluid Structure Interactions ◽

10.1115/pvp2003-1952 ◽

2003 ◽

Author(s):

Melih Demir ◽

Govert de With ◽

Arne E. Holdo̸

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Flow Field ◽

Unsteady Flow ◽

Mesh Refinement ◽

Research Centre ◽

Shear Stresses ◽

Wall Region ◽

Grid Adaptation ◽

Computational Fluid Dynamics Cfd

At present a large number of fluid dynamics applications are found in aerospace, civil and automotive engineering, as well in medical related fields. In many applications the flow field is turbulent and the computational modelling of such flows remains a difficult task. To resolve all turbulent flow phenomena for flow problems where turbulence is of key interest is a priori not feasible in a Computational Fluid Dynamics (CFD) investigation with a conventional mesh. The use of a Dynamic Grid Adaptation (DGA) algorithm in a turbulent unsteady flow field is an appealing technique which can reduce the computational costs of a CFD investigation. A refinement of the numerical domain with a DGA algorithm requires reliable criteria for mesh refinement which reflect the complex flow processes. At present not much work has been done to obtain reliable refinement criteria for turbulent unsteady flow. The purpose of the work is to implement a new refinement technique for the boundary layer in the vicinity of the wall. It is aimed to model the flow around an airfoil with a LES turbulence model and a new DGA algorithm. In addition to that several simulations have been carried out for parametric studies. In these studies the incompressible solver in REACFLOW has been used. This Computational Fluid Dynamics (CFD) code REACFLOW was developed in collaboration with the joint Research Centre (JRC) in Italy. The following aims are aspired: • A new mesh refinement criteria method suitable for boundary layers; • To carry out LES simulations to establish the performance of the refinement criteria. The new criteria which are created in this work are for the near wall region. This criteria uses the wall shear stresses for the refinement technique. For the main flow stream the refinement criteria proposed by de With et al [6] will be used.

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