Numerical and experimental investigation of the heat transfer of spherical particles in a packed bed with an implicit 3D finite difference approach

Numerical and experimental investigation of the heat transfer of spherical particles in a packed... Heat transfer in packed or fluidized beds in the presence of a surrounding fluid is an important phenomenon which is relevant to numerous industrial applications. Here we extend an earlier derived 3D heat transfer model (Oschmann et al. in Powder Technol 291:392–407, 2016) to take into account particle-fluid heat convection in the case of Biot numbers $$Bi\gg 1$$ B i ≫ 1 . The Discrete Element Method (DEM) which is coupled with the commercial Computational Fluid Dynamics (CFD) package ANSYS Fluent is used as the modelling framework. As a first approximation of the flow induced inhomogeneity of the local heat transfer on the particle surface a distribution function is employed. To validate the resolved heat transfer model, we compare DEM/CFD simulations of three different materials (wood, Polyoxymethylene (POM) and aluminum) with performed experiments. This firstly includes cases where particle surface temperatures are compared with measurements of an infrared camera. Secondly, a numerical study of the average bed temperatures of particle core and surface is conducted to show the differences of the used materials. Thirdly, the core temperatures of three selected particles are compared against experiments. The DEM/CFD framework provides an accurate description of the temperature evolution where the wall effects are negligible. Close to the walls a qualitative agreement can only be achieved for materials with low thermal conductivities. As a consequence of this, in the second part of our investigation we provide various CFD simulations for the heating of an aluminum oxide wall which is required for the evaluation of the particle surface temperatures measured by an infrared camera. The simulation results show the same tendencies as the experiments, underline the complexity of the heat transfer at the walls and are a first step for the formulation of a complex particle-wall heat transfer model in the context of a DEM/CFD framework. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Granular Matter Springer Journals

Numerical and experimental investigation of the heat transfer of spherical particles in a packed bed with an implicit 3D finite difference approach

Loading next page...
 
/lp/springer_journal/numerical-and-experimental-investigation-of-the-heat-transfer-of-vKmcEyoQ9M
Publisher
Springer Berlin Heidelberg
Copyright
Copyright © 2017 by Springer-Verlag Berlin Heidelberg
Subject
Physics; Soft and Granular Matter, Complex Fluids and Microfluidics; Engineering Fluid Dynamics; Materials Science, general; Geoengineering, Foundations, Hydraulics; Industrial Chemistry/Chemical Engineering; Engineering Thermodynamics, Heat and Mass Transfer
ISSN
1434-5021
eISSN
1434-7636
D.O.I.
10.1007/s10035-017-0711-z
Publisher site
See Article on Publisher Site

Abstract

Heat transfer in packed or fluidized beds in the presence of a surrounding fluid is an important phenomenon which is relevant to numerous industrial applications. Here we extend an earlier derived 3D heat transfer model (Oschmann et al. in Powder Technol 291:392–407, 2016) to take into account particle-fluid heat convection in the case of Biot numbers $$Bi\gg 1$$ B i ≫ 1 . The Discrete Element Method (DEM) which is coupled with the commercial Computational Fluid Dynamics (CFD) package ANSYS Fluent is used as the modelling framework. As a first approximation of the flow induced inhomogeneity of the local heat transfer on the particle surface a distribution function is employed. To validate the resolved heat transfer model, we compare DEM/CFD simulations of three different materials (wood, Polyoxymethylene (POM) and aluminum) with performed experiments. This firstly includes cases where particle surface temperatures are compared with measurements of an infrared camera. Secondly, a numerical study of the average bed temperatures of particle core and surface is conducted to show the differences of the used materials. Thirdly, the core temperatures of three selected particles are compared against experiments. The DEM/CFD framework provides an accurate description of the temperature evolution where the wall effects are negligible. Close to the walls a qualitative agreement can only be achieved for materials with low thermal conductivities. As a consequence of this, in the second part of our investigation we provide various CFD simulations for the heating of an aluminum oxide wall which is required for the evaluation of the particle surface temperatures measured by an infrared camera. The simulation results show the same tendencies as the experiments, underline the complexity of the heat transfer at the walls and are a first step for the formulation of a complex particle-wall heat transfer model in the context of a DEM/CFD framework.

Journal

Granular MatterSpringer Journals

Published: Jun 22, 2017

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off