This thesis is mainly concerned with the study of flow and pressure in silos during filling and discharging. It describes the numerical and experimental studies undertaken to investigate the effects of filling modes and inserts on the flow and pressure in silos. The numerical investigations were performed using two different finite element codes: SILO from Sweden and the commercial Abaqus Code. Finite Element (FE) models were developed to simulate a progressive filling process, and used to investigate the development of filling pressures along the walls of a steep hopper and a shallow hopper. Two filling modes were simulated: a concentric filling mode and a distributed filling mode. The FE results obtained were compared with the predictions from classic theories, and for the case of the shallow hopper, also with the results measured in large scale experiments. The investigation of the effect of inserts on silo flow using the FE code SILO shows that the insert converts the discharge pattern from funnel flow to mass flow in a silo with a modest inclination hopper. Parametric study further exhibited that a combination of a careful positioning of the insert and a reduction of wall friction between the solid and hopper walls would improve the silo discharge pattern in a silo with a shallower hopper. The residence times of tracers were measured to identify the flow pattern in the experiments with a double cone insert and compared with the numerical predictions.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:649561 |
| Date | January 2004 |
| Creators | Ding, Songxiong |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/10875 |
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