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Silo discharge of binary granular mixtures.
M Madrid1, K Asencio2, D Maza2
1Departamento Ingeniería Mecánica, Facultad Regional La Plata, Universidad Tecnológica Nacional, CONICET, Avenida 60 Esquina 124, La Plata 1900, Argentina.
Physical Review. E
|September 28, 2017
Summary
The mass flow rate of granular materials discharged from silos is predictable using existing formulas, even with mixtures of different particle sizes. Particle size distribution significantly impacts volume fraction but not velocity profiles.
Area of Science:
- Granular physics
- Fluid dynamics
- Material science
Background:
- Understanding granular flow is crucial for industries handling bulk materials.
- Discharge dynamics from silos are complex, influenced by particle properties and silo geometry.
- Previous studies primarily focused on monodisperse granular flows.
Purpose of the Study:
- To investigate the mass flow rate of bidisperse granular mixtures from 3D silos.
- To analyze the effect of particle size ratio on volume fraction and velocity profiles.
- To adapt existing mass flow rate models for granular mixtures.
Main Methods:
- Numerical simulations of granular discharge.
- Experimental validation of simulation results.
- Analysis of volume fraction and velocity profiles across the orifice.
Main Results:
- Silo discharge velocity profiles are insensitive to mixture composition.
- Volume fraction profiles are significantly affected by the ratio of coarse to fine particles.
- An effective particle size can characterize the mixture for flow rate predictions.
Conclusions:
- Existing mass flow rate expressions for monodisperse particles are applicable to bidisperse mixtures.
- The study provides a method to predict granular flow rates for mixed particle sizes.
- Findings contribute to more accurate modeling of granular material discharge.
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