Journal of Korea Technical Association of The Pulp and Paper Industry (펄프종이기술)

Korea Technical Association of the Pulp and Paper Industry (한국펄프종이공학회)
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Influence of Design of Turbulence Generator on Flow Behavior in Pilot Headbox

  • Youn Hye Jung (Department of Forest Sciences, College of Agriculture and Life Sciences, Seoul National University) ;
  • Lee Hak Lae (Department of Forest Sciences, College of Agriculture and Life Sciences, Seoul National University) ;
  • Chin Seong Min (Department of Forest Sciences, College of Agriculture and Life Sciences, Seoul National University)
  • Published : 2004.12.01
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Abstract

The geometry of headboxes is of great importance in obtaining good formation, even basis weight profile and fiber orientation. Therefore, many attentions have been made to examine the influence of the geometry of headboxes on the flow behavior. In this study, to evaluate flow behavior in headboxes, three types of turbulence generators were examined using pilot headbox. Velocity profiles in MD and CD were measured using a pressure monitoring system and flow in headboxes was visualized by dye injection method. CD velocity profiles at three different locations inside the slice of Type A headbox showed that the velocity increased downstream to slice exit and had a pattern with four humps due to the persisting wall effect of step diffusors. Results from the evaluation of normalized velocity profile and flow visualization showed that L-shaped Type C headbox caused a large pressure drop but it lacked in flow stabilizing ability.

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References

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