| 摘要 |
A vortex flow control device is manufactured by forming a template unit 2 having end walls 4, 6 of which the wall 4 has an outlet opening 5 and a partial outer wall 8, providing has an opening 16. A plate 26 is secured to the template unit at transition portion 24 and along end wall edges 18, 20 to partially close the opening to leave an inlet. The size of the plate 26 is selected to produce an inlet sized for the flow characteristics for the finished device. The plate 26 or terminal portion departs from the direction of vortex flow circulating in the device, e.g. becomes tangential or curves outward (Fig. 12), to increase turbulence at the inlet and increase flow resistance. There may be a tangential wall portion 14 on the other side of the inlet. The device may be one piece moulded and the opening cut to size. |
