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Experimental Characterization of Meso-Scale Processes

  • Jinghai Li
  • Wei Ge
  • Wei Wang
  • Ning Yang
  • Xinhua Liu
  • Limin Wang
  • Xianfeng He
  • Xiaowei Wang
  • Junwu Wang
  • Mooson Kwauk
Chapter

Abstract

Meso-scale structures possess spatio-temporal dynamic heterogeneity, which requires fine space and time resolutions of quantifying parameters to be fully understood. The EMMS group has been focusing on numerical simulation and experimental characterization of multiscale processes in multi-phase complex systems since the 1980s. This chapter introduces several experimental and measurement technologies developed or extended by the EMMS group to quantitatively characterize meso-scale processes and particle clustering dynamics as well as their effects on transport properties in gas-solid systems. These technologies have allowed the EMMS theory to be experimentally validated and facilitated the construction of a rudimentary platform for virtual process engineering (VPE).

Keywords

Computerized tomography (CT) Fluid dynamics Gas backmixing Gas-solid fluidization Mass transfer Meso-scale process Optical fiber Particle image velocimetry (PIV) Phase Doppler particle analyzer (PDPA) Virtual process engineering (VPE) 

Notation

Φ

Phase shift, -

a

Acceleration, m/s2

A

Effective flow area, gas-particle contacting area, cross-section area, m2

C

Concentration, g/m3

d

Diameter, m

D

Diffusion coefficient, m2/s

F

Fraction, -

f

Frequency or dense phase volume fraction, Hz (-)

Gs

Solids flow rate, kg/m2 s

Gt

Particle gate time, s

h, H

Height, m

I

Ray intensity, -

It

Particle interval time, s

K

Optical constant, -

kg

Mass transfer rate, m/s

Kg

Volumetric mass transfer coefficient, 1/s

l, L

Distance, width, m

Lf

Lens focal length, m

M

Amplification factor, -

N

Number, -

R

Radium, m

Re

Reynolds number, -

s

Length of detector, m

Sh

Sherwood number, -

t

Time, s

U

Superficial velocity, m/s

u

Velocity, m/s

W

Width, m

w, m

Mass, kg

Δd

Displacement, m

Δl

Space between two detectors, m

λ

Wave length, m

ρ

Density, kg/m3

α

Half of the beam crossing angle, -

β

Crossed angle between two fibers or rays, -

δ

Distance between two fibers or fringe spacing, m

ε

Voidage, -

μ

Linear decaying factor, -

θ

Incident or collection angle, -

Subscripts

b

Bed

c

Dense phase, center

cl

Cluster

f

Dilute phase, fluid, fiber

g

Gas

in

Inlet

max

Maximum

mf

Minimum fluidization

min

Minimum

out

Outlet

p

Particle

s

Sampling, saturation

tr

Transient

w

Wall, beam waist

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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Jinghai Li
    • 1
  • Wei Ge
    • 1
  • Wei Wang
    • 1
  • Ning Yang
    • 1
  • Xinhua Liu
    • 1
  • Limin Wang
    • 1
  • Xianfeng He
    • 1
  • Xiaowei Wang
    • 1
  • Junwu Wang
    • 1
  • Mooson Kwauk
    • 1
  1. 1.Institute of Process EngineeringChinese Academy of SciencesBeijingPeople’s Republic of China

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