| 摘要 |
1368638 Airfoil web dryer OVERLY Inc 16 Nov 1971 [16 Nov 1970 26 Aug 1971] 53220/71 Heading F4G One or more airfoil nozzles 4 are disposed on at least one side of a moving web 1 (as in Specification 1,291,583) and each nozzle 4 comprises a flat surface 9 following the slot 7 to cause turbulent flow of air in the space 12, the heated air being discharged from the slot 7 at a velocity not less than 3,300 (e.g. 15,000) feet per minute, the length of the flat surface 9 in the direction of air flow, (which is equal to the spacing between surface 9 and web 1) and the width of the nozzle slot 7 being in the ratio range 40-100 (e.g. 60 or 65), and the Reynolds number in the turbulent space 12 being in the range 4000 to 10,000. Each nozzle 4 terminates in a sharp edge 13 to reduce the Coanda effect. Each nozzle 4 is supplied with air by a central duct 6, and has closed ends. The width of the slot is between 0À04 and 0À125 inch, preferably more than 0À06 inch. |
