Doctoral Thesis

Limit Modes of Particulate Materials Classifiers

Final Thesis 7.68 MB Summary of Thesis 3.6 MB

Author of thesis: Ing. Martin Adamčík, Ph.D.

Acad. year: 2017/2018

Supervisor: prof. Ing. Tomáš Svěrák, CSc.

Reviewers: doc. Ing. Roman Fekete, Ph.D., prof. Ing. František Štěpánek, Ph.D.

Abstract:

With material science demands on ever smaller particle sizes, new approaches and effective methods of their classification are needed. Turbulent flow field patterns and particle trajectories inside of a dynamic air classifier are investigated. Increasing computing power together with new turbulence models and approaches to simulate complex fully turbulent problems by solving Navier-Stokes equations allows studying and capturing smaller flow structures and properties more accurately. Particles below 10 microns are more susceptible to smaller local vortexes and particle fates are therefore more dependent on these local structures. Area of focus are the conditions required for classification of particles with sizes below 10 microns as this size is at the limit of air classification method possibilities. CFD software and the latest knowledge in turbulence modelling are used to numerically simulate flow field inside a dynamic air classifier. Effects of varying operating parameters on flow patterns and discrete phase classification outputs are investigated. Experimental verification of the simulated flow fields includes advanced imaging method (PIV) measurement of flow velocity and is used to visualize flow field structures in the classifier rotor blade passageway region. Predicted particle trajectories and their fates are experimentally verified by classification trials carried out on dynamic air classifier and the particle distribution curves are established by laser diffraction method. Tromp curves and efficiency of classification process are studied.

Keywords:

Rotor air classifier, fine particle classification, Tromp curve, particle image velocimetry (PIV), laser diffraction method, numerical simulation CFD

Date of defence

12.12.2017

Result of the defence

Defended (thesis was successfully defended)

znamkaPznamka

Process of defence

Přínos - snímání experimentálních dat v kritické oblasti třídění - aplikace škály současných simulačních hodnot

Language of thesis

English

Faculty

Department

Study programme

Applied Sciences in Engineering (D4A-K)

Field of study

Applied Mechanics (D-IME)

Composition of Committee

prof. Ing. Miroslav Raudenský, CSc. (předseda)
prof. Ing. František Štěpánek, Ph.D. (člen)
doc. Ing. Roman Fekete, Ph.D. (člen)
prof. Ing. Ĺubomír Lapčík, CSc. (člen)
prof. Ing. Michal Veselý, CSc. (člen)
prof. Ing. Mirko Dohnal, DrSc. (člen)

Supervisor’s report
prof. Ing. Tomáš Svěrák, CSc.

viz. posudek v pdf.

Reviewer’s report
doc. Ing. Roman Fekete, Ph.D.

viz. posudek v pdf.
File inserted by the reviewer Size
Posudek oponenta [.pdf] 111,15 kB

viz. posudek v pdf.
File inserted by the reviewer Size
Posudek oponenta [.pdf] 298,90 kB