Heat transfer rates in sheared beds of inertial particles at high Biot numbers

Thomas Forgber, Bhageshvar Mohan, Christoph Kloss, Stefan Radl

Research output: Contribution to journalArticleResearchpeer-review

Abstract

We investigate heat conduction rates through the contact network of sheared granular materials that consist of particles with a density much larger than that of the ambient fluid. The tool ParScale, a finite difference solver for intra-particle transport processes, is coupled to the discrete element method solver LIGGGHTS to carry out the simulations. Heat transfer to the surrounding fluid is considered via a fixed heat transfer coefficient. We identify a combination of Biot and Peclet number as the key non-dimensional influence parameter to describe the non-dimensional heat flux through the particle bed and provide an analytical solution to calculate mean particle temperature profiles. Simulations over a wide range of particle volume fractions, Biot and Peclet numbers are then performed in order to develop a continuum model for the heat flux. We show that for Biot numbers below 10−3 our results agree with a simple model based on a uniform particle temperature. However, for Biot numbers above a certain threshold, the conductive heat flux decreases substantially depending on the flow situation, and temperature gradients within the particle should be considered in order to correctly predict the heat transfer rate to the surrounding fluid.
Original languageEnglish
Number of pages23
JournalGranular matter
Volume19
Issue number14
DOIs
Publication statusPublished - 17 Jan 2017

Fingerprint

Biot number
Heat flux
beds
Peclet number
heat transfer
Heat transfer
Fluids
Granular materials
heat flux
Heat conduction
Finite difference method
Thermal gradients
Heat transfer coefficients
Particles (particulate matter)
Volume fraction
fluids
Temperature
granular materials
heat transfer coefficients
conductive heat transfer

Keywords

  • Discrete Element Method
  • ParScale
  • Thermal Fluxes

Fields of Expertise

  • Advanced Materials Science

Cite this

Heat transfer rates in sheared beds of inertial particles at high Biot numbers. / Forgber, Thomas; Mohan, Bhageshvar; Kloss, Christoph; Radl, Stefan.

In: Granular matter, Vol. 19, No. 14, 17.01.2017.

Research output: Contribution to journalArticleResearchpeer-review

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