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✓Reasonable agreement with experimental results.
✓ Parcel Contact Coarse Grain Model does not significantly affect results.
✓ RUNTIME:
T. Eppinger, F. Klippel, L. Becker, R. Aglave, D. Russ
Siemens Digital Industries Software
E-Mail: [email protected]
Industrial processes often encompass a variety of
significant physical phenomena. This is especially true
with granular flow problems, as solid mechanics, fluid
dynamics and the interaction of the two all
contribute. While modeling techniques can capture
aspects of these problems, it is difficult to capture every
relevant phenomenon with a single technique. When
only a portion of the physics are captured, the usefulness
of such a simulation is limited. A more comprehensive
Multiphysics approach which combines multiple modeling
techniques is necessary. For granular flow problems,
CFD-DEM coupled simulations are one such approach.
A common roadblock to the widespread utilization of
coupled CFD-DEM simulation is the high computational
cost for large scale problems. Yet in an increasingly
competitive industrial environment, the opportunity cost of
missed innovation dwarfs this computational
cost. Numerical techniques such as coarse grain methods
can help reduce the computational cost and make
engineering innovation more attainable.
Spouted beds, commonly used for particle coating or drying,
are one such application to which coupled CFD-DEM
techniques are well suited. In this work, Simcenter STAR-
CCM+ was used to compare the efficacy and efficiency of
different coarse grain techniques for a spouted bed
application. Results have been compared qualitatively and
quantitative against experimental data. Bed expansion and
pressure drop are generally well predicted.
References[1] Vitalij Salikov, Sergiy Antonyuk, Stefan Heinrich, Vinayak S. Sutkar, Niels G. Deen,
J.A.M. Kuipers, Characterization and CFD-DEM modelling of a prismatic spouted bed,
Pow. Tech. 270 (2015), 622-636.
Particle Coarse GrainingSimulation SetupGeometry Setup
• 326k trimmed (hexahedral) cells
• Fully 2-way coupled DEM simulation
• 235k particles
• diameter d = 1.8 mm,
• density ρ = 1040 kg/m³ and Young‘s Modulus = 100 MPa
• Particle-particle friction and restitution coefficient: 0.5, 0.75
• Particle-wall friction and restitution coefficient: 0.9, 0.9
• Gidaspow drag law & pressure gradient
• Simulation time approx. 7s
Impact of Coarse Grain Techniques on CFD-DEM Simulation of a
Prismatic Spouted Bed
Introduction
Methods
Conclusion
Results
Comparison between CFD-DEM and experimental results.
ሶ 𝑽𝑮𝒂𝒔=
0.0
15 m
³/s
Parcel Contact Coarse Grain Model , 10 particle/parcel
No Coarse Graining
ሶ 𝑽𝑮𝒂𝒔=
0.0
23 m
³/s
No Coarse Graining
Parcel Contact Coarse Grain Model , 10 particle/parcel
ሶ𝑽𝑮𝒂𝒔=0.015 m³/s
Exp.: 5.1Hz
Exp.: pressure fluctuation
800 -1500 Pa
CFD-DEM: 3098 CPU hours
CFD-DEM with CG: 98 CPU hours
particles parcel
• Fluid-particle interaction (CFD-DEM coupling)
is calculated based on particle size
• Each particle has the same properties
• Collision simulation is done base on parcel
size and allows larger time-steps.
195
250
100
60°
Ave.
Part
icle
Heig
ht
[m]
Exp.: 0.102 m
Unrestricted
