| 摘要 |
A turbulence generator (8) consists of a fixed part (9) containing fixed sections (10) of an array of parallel ducts, and a movable part (14) with, for each duct, a movable section (15) with a diameter smaller than the minimal diameter of the adjacent fixed section (10). If the overall rate of the stock flow is large a maximal flow velocity sufficient for producing a required degree of turbulence can be reached with the fixed part (9) alone and the movable part (14) is removed from the flow path. Where the flow rate is too small for that the movable part (14) is placed in the flow path and the minimal overall cross section area reduced. This results in an increase of the maximal velocity of the flow which is then again sufficient to engender turbulence of the desired degree and intensity. In this way two different ranges of paper which require different ranges of flow rates can be produced. |
