Abstract
The dynamics of fibre suspension flow, especially breakup and re-formation of fibre flocs in a closed channel flow past a forward facing step was studied experimentally using fast CCD camera imaging and image analysis techniques that allow for simultaneous measurement of floc size and turbulent flow field of fibres. The recirculation eddy downstream of the expansion step was found to exist only if the step height exceeds the mean fibre length. When existing, the behavior of the eddy is similar to that of Newtonian fluis flows. Experimental correlations between floc size and turbulent flow quantities were found indicating that the ratio of the minimum floc sizefound at the end of the recirculation region and the size upstream of the step is strongly correlated with the size of the largest scales of the turbulent field and less directly with the total turbulent intensity of the flow immediately after the step. In addition, an approximate power law scaling behavior of the floc size with the turbulent intensity was found within the decaying turbulence region downstream of the recirculation eddy.
| Original language | English |
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| Title of host publication | Advances in Paper Science and Technology |
| Subtitle of host publication | Transactions of the 13th Fundamental Research Symposium |
| Editors | S.J. l'Anson |
| Publisher | Pulp & Paper Fundamental Research Society |
| Number of pages | 15 |
| ISBN (Print) | 978-0-9545272-3-5, 0-9545272-3-2 |
| Publication status | Published - 2005 |
| MoE publication type | A4 Article in a conference publication |
| Event | 13th Fundamental Research Symposium - Cambridge, United Kingdom Duration: 11 Sept 2005 → 16 Sept 2005 |
Conference
| Conference | 13th Fundamental Research Symposium |
|---|---|
| Country/Territory | United Kingdom |
| City | Cambridge |
| Period | 11/09/05 → 16/09/05 |