Numerical Study of Particle Transport and Deposition in a Horizontal Channel Using a Lagrangian-Based Modelling Approach

Abstract Texas A&M University is participating in the U.S. Department of Energy (DOE) Office of Nuclear Energy’s Versatile Test Reactor (VTR) program to develop instrumentation and tools for a proposed fast spectrum test reactor. Our research project aims to develop and implement techniques to quantify the transport and deposition of fission products in the primary system of Gas Fast Reactors (GFRs) and ultimately in the reactor confinement. Developed techniques will be performed and tested in the NGNP Reactor Building experimental facility, which was previously 1/28 downscaled from General Atomics 350 MWth and built to study the reactor building responses to depressurization accidents. Prior to applying the techniques to the scaled facility, it is essential to verify and validate the performance of developing techniques using numerical simulations and quantify their associated uncertainties. This manuscript presents our numerical study of particle transport and deposition in an experimental channel. The channel has three test sections, each has 3-inch square cross-section, 24 inches in length for a combined total length of 72 inches. The experimental facility is built using transparent materials, allowing the applications of non-intrusive, laser-based measurement techniques, such as Particle Image Velocimetry (PIV) and Particle Tracking Velocimetry (PTV). Details of the experimental setup, measurement techniques, and results of flow field characteristics and particle transports in the channel will be presented in an accompanied manuscript. The simulation domain is built upon the geometrical dimensions of the experimental facility, while upstream flow characteristics of the square channel obtained by PIV measurements are used as boundary conditions. State-of-the-art Lagrangian approach with random walk model is employed to investigate behaviors of surrogate particles within the square channel, coupled with computational fluid dynamics (CFD) model. While the main stream in the channel is solved by Eulerian turbulent model, motion of particles is tracked in Lagrangian framework. It is assumed that well-mixed air-particle mixture at a constant temperature is injected into the horizontal channel. Drag force, gravity force and turbophoresis force are adapted on this simulation and their competition are investigated. Comparisons and validations of simulations and measurements on the flow fields downstream of the channel and characteristics of particle transports and depositions within the square channel will be systematically investigated. Experimental and numerical uncertainties will be quantified using the accepted standard approaches.

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Experimental Study of Surrogate Particle Transport and Deposition in a Square Channel Using Particle Tracking Technique

Volume 6: Energy ◽

10.1115/imece2019-11811 ◽

2019 ◽

Author(s):

Daniel Orea ◽

Thien Nguyen ◽

Rodolfo Vaghetto ◽

N. K. Anand ◽

Yassin A. Hassan ◽

...

Keyword(s):

Experimental Study ◽

Fluid Flow ◽

Particle Tracking ◽

Particle Transport ◽

Particle Deposition ◽

Numerical Study ◽

Flow Characteristics ◽

Test Facility ◽

Square Channel ◽

Fluid Flow Characteristics

Abstract This paper presents an experimental study of hydrodynamics flow characteristics and particle transport in a test facility. Experimental measurements of fluid flow and particle deposition are studied under isothermal conditions using particle image velocimetry (PIV) and particle tracking velocimetry (PTV) techniques. These non-intrusive optical measurement techniques have been applied in experiment conditions of Reynolds number Re = 5,077 in a 3-inch square channel and 72-inches in total length. The fluid within the channel is air seeded with aerosol droplets while the measurements of particle transport is facilitated using surrogate particles dispersed in the channel flow. Results obtained from the PIV and PTV measurements included the hydrodynamics fluid flow characteristics, and characteristics of particle transports, such as particle velocity, particle diameter distributions and particle concentration profiles. Results from the preliminary test have shown 11.08% deposition of particles. To supplement this experimental work, upstream fluid flow characteristics were provided as boundary conditions for a comparable numerical study.

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Deposition Velocity and Penetration Efficiency in a Square Channel Using a Lagrangian-Based Modeling Approach

Volume 1: Beyond Design Basis; Codes and Standards; Computational Fluid Dynamics (CFD); Decontamination and Decommissioning; Nuclear Fuel and Engineering; Nuclear Plant Engineering ◽

10.1115/icone2020-16907 ◽

2020 ◽

Author(s):

Byung-Hee Choi ◽

Daniel Orea ◽

Thien Nguyen ◽

N. K. Anand ◽

Yassin Hassan ◽

...

Keyword(s):

Particle Deposition ◽

Numerical Study ◽

Numerical Technique ◽

Deposition Velocity ◽

Stokes Number ◽

Department Of Energy ◽

Main Stream ◽

Proof Of Concept ◽

Square Channel ◽

Lagrangian Framework

Abstract Texas A&M University is working on the development of gas cooled fast reactor cartridge loop under the Department of Energy VTR program. Our research project aims to develop and implement techniques to quantify the transport and deposition of particle inside the cartridge loop. Before the developed techniques are applied in a complicated actual facility, it is essential to verify and validate their performance using numerical simulations and to quantify their uncertainties. This article presents a numerical study of particle transport and deposition in a proof-of-concept facility. The proof-of-concept facility houses a series of three square duct test sections, each of which has a cross-section of 3 in.2 and a length of 24 in., for a combined total length of 72 in. The numerical simulation domain is based on the geometrical dimensions of the experimental facility. The main stream in the channel is solved using the Eulerian turbulence model, and the particle motion is interpreted in the Lagrangian framework. It is assumed that a well-mixed air–particle mixture at a constant temperature is injected into the horizontal channel. Lagrangian simulations of surrogate particles allow us to understand their behavior precisely. The Reynolds stress model is selected to reproduce the secondary flow and the associated secondary drag force. The state-of-the-art Lagrangian approach, in combination with a random walk model coupled with a computational fluid dynamics model, is employed to investigate the behaviors of the surrogate particles within the square channel. Gravitational settling is also considered. The deposition velocity and penetration efficiency are estimated for representing the characteristics of particle deposition in the proof-of-concept facility. Because the conventional method of measuring the deposition velocity is based on the Eulerian framework, it is not suitable for direct adoption in the Lagrangian framework. This study proposes a numerical technique to measure the deposition velocity; this technique can be efficiently used in the Lagrangian framework of the simulation. The results agree well with both our experimental measurements and correlations available in the literature. Using this technique, the correlations for the deposition velocity are established as functions of the normalized channel length, Stokes number, and Reynolds number. Finally, the relationship between the deposition velocity and penetration efficiency is examined, and a correlation is proposed. Consequently, the penetration efficiency can be directly compared with several conventional reference data based on the deposition velocity.

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Optimized Chaotic Heat Exchanger Configurations for Process Industry: A Numerical Study

Volume 1B, Symposia: Fluid Machinery; Fluid Power; Fluid-Structure Interaction and Flow-Induced Noise in Industrial Applications; Flow Applications in Aerospace; Flow Manipulation and Active Control: Theory, Experiments and Implementation; Fundamental Issues and Perspectives in Fluid Mechanics ◽

10.1115/fedsm2013-16115 ◽

2013 ◽

Cited By ~ 2

Author(s):

Akram Ghanem ◽

Thierry Lemenand ◽

Dominique Della Valle ◽

Hassan Peerhossaini

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Numerical Study ◽

Three Dimensional ◽

Flow Characteristics ◽

Process Intensification ◽

Point Of View ◽

Square Duct ◽

Square Channel ◽

Duct Geometry

A numerical investigation of chaotic laminar flow and heat transfer in isothermal-wall square-channel configurations is presented. The computations, based on a finite-volume method with the SIMPLEC algorithm, are conducted in terms of Péclet numbers ranging from 7 to 7×105. The geometries, based on the split-and-recombine (SAR) principle, are first proposed for micromixing purposes, and are then optimized and scaled up to three-dimensional minichannels with 3-mm sides that are capable of handling industrial fluid manipulation processes. The aim is to assess the feasibility of this mass- and heat-transfer technique for out-of-laboratory commercial applications and to compare different configurations from a process intensification point of view. The effects of the geometry on heat transfer and flow characteristics are examined. Results show that the flux recombination phenomenon mimicking the baker’s transform in the SAR-1 and SAR-2 configurations produces chaotic structures and promotes mass transfer. This phenomenon also accounts for higher convective heat transfer exemplified by increased values of the Nusselt number compared to the chaotic continuous-flow configuration and the baseline plain square-duct geometry. Energy expenditures are explored and the overall heat transfer enhancement factor for equal pumping power is calculated. The SAR-2 configuration reveals superior heat-transfer characteristics, enhancing the global gain by up to 17-fold over the plain duct heat exchanger.

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Numerical study of nanoscale and microscale particle transport in realistic lung models with and without stenosis

International Journal of Multiphase Flow ◽

10.1016/j.ijmultiphaseflow.2021.103842 ◽

2021 ◽

pp. 103842

Author(s):

Md. M Rahman ◽

Ming Zhao ◽

Mohammad S Islam ◽

Kejun Dong ◽

Suvash C Saha

Keyword(s):

Particle Transport ◽

Numerical Study

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IMPULSIVELY STARTED FLOW TOPOLOGY AROUND TANDEM ARRANGEMENT OF TWO SQUARE CYLINDER AT INCIDENCE

International Journal of Modern Physics Conference Series ◽

10.1142/s201019451200863x ◽

2012 ◽

Vol 19 ◽

pp. 100-108

Author(s):

SUNIL MANOHAR DASH ◽

THONG-SEE LEE

Keyword(s):

Numerical Study ◽

Flow Direction ◽

Main Stream ◽

Angle Of Incidence ◽

Flow Topology ◽

Pressure Distributions ◽

Square Prism ◽

Tandem Square Cylinders ◽

Type 3

Numerical study of impulsively started flow over two tandem square cylinders where former cylinder is rotated at angles (0-45deg) to main stream flow direction keeping later one inline to flow stream with a separation of twice the side length of square prism between the centers of cylinders is performed using FVM code solver FLUENT 6.3.26. Temporal developments of streamlines around cylinders are studied for laminar flow regime ( Re = 100). Flow pattern formed are categories into Type-1, Type-2, Type-3 & Type-4 as per vortices growth at corresponding angle of incidence which are novel results of present study. Pressure distributions over the surface of cylinders are also monitored.

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Numerical study on modulation of microbubbles on turbulence frictional drag in a horizontal channel

Ocean Engineering ◽

10.1016/j.oceaneng.2014.02.012 ◽

2014 ◽

Vol 81 ◽

pp. 58-68 ◽

Cited By ~ 18

Author(s):

M.J. Pang ◽

J.J. Wei ◽

B. Yu

Keyword(s):

Numerical Study ◽

Horizontal Channel ◽

Frictional Drag

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Tracer trajectories and displacement due to a micro-swimmer near a surface

Journal of Fluid Mechanics ◽

10.1017/jfm.2015.269 ◽

2015 ◽

Vol 773 ◽

pp. 498-519 ◽

Cited By ~ 23

Author(s):

A. J. T. M. Mathijssen ◽

D. O. Pushkin ◽

J. M. Yeomans

Keyword(s):

Particle Transport ◽

Numerical Study ◽

Tracer Particle ◽

Persistence Length ◽

Theoretical Work ◽

Solid Boundary ◽

Tracer Transport ◽

Tracer Particles ◽

Recent Theoretical Work ◽

Run And Tumble

We study tracer particle transport due to flows created by a self-propelled micro-swimmer, such as a swimming bacterium, alga or a microscopic artificial swimmer. Recent theoretical work has shown that as a swimmer moves in the fluid bulk along an infinite straight path, tracer particles far from its path perform closed loops, whereas those close to the swimmer are entrained by its motion. However, in biologically and technologically important cases tracer transport is significantly altered for swimmers that move in a run-and-tumble fashion with a finite persistence length, and/or in the presence of a free surface or a solid boundary. Here we present a systematic analytical and numerical study exploring the resultant regimes and their crossovers. Our focus is on describing qualitative features of the tracer particle transport and developing quantitative tools for its analysis. Our work is a step towards understanding the ecological effects of flows created by swimming organisms, such as enhanced fluid mixing and biofilm formation.

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