Cyclopedia of heating, plumbing and sanitation; a complete reference work . Fig. 115. Centrifugal Fan in -Three-Quarter Housing. Used where Headroom isLimited; Extra Space Provided by Pit under Floor-Level. 172 HEATING AND VENTILATION 103 Fans arc made both with double and with single inlets, theformer being called blowers and the latter exhausters. The size ofa fan is commonly expressed in inches, which means the approximateheight of the casing of a full-housed fan. The diameter of the wheelis usually expressed in feet, and can be found in any given ease bydividing the size in inches by 20. F
Cyclopedia of heating, plumbing and sanitation; a complete reference work . Fig. 115. Centrifugal Fan in -Three-Quarter Housing. Used where Headroom isLimited; Extra Space Provided by Pit under Floor-Level. 172 HEATING AND VENTILATION 103 Fans arc made both with double and with single inlets, theformer being called blowers and the latter exhausters. The size ofa fan is commonly expressed in inches, which means the approximateheight of the casing of a full-housed fan. The diameter of the wheelis usually expressed in feet, and can be found in any given ease bydividing the size in inches by 20. For example, a 120-inch fan has awheel 120 -*- 20 = 6 feet in Pig. 146. Cone Fan. Discharges through Opening In Wall into a Plenum ChamberConnecting with Distributing Ducts. Theory of Centrifugal Fans. The action of a fan is affected to such an extent by the various conditions under which it operates,that it is impossible to give fixed rules for determining the exactresults to be expected in any particular instance. This being thecase, it seems best to take up the matter briefly from a theoretical 173 h\\ HEATING A\D VENTILATION standpoint, and then show what corrections arc necessary in thecase of ;i given fan under actual working conditions. There are various methods for determining the capacity of afan at differenl speeds, and the power necessary to drive it; eachmanufacturer has his own formulae for this purpose, based upontests of his own particular fans. The methods given here applyin a general way to fans having proportions which represent theart rai/i of several standard makes; and the results obtained will he
Size: 1474px × 1696px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthoramericanschoolchicago, bookcentury1900, bookdecade1900
