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References: Fan Laws, System Effect and Sound

  1. Affinity laws - Wikipedia - States the fan and pump affinity laws for changes in speed and impeller diameter. A compact cross-check for the chapter's fan laws, speed change and size change calculations.

  2. Sound pressure - Wikipedia - Defines sound pressure and sound pressure level in decibels referenced to 20 micropascals, and how level falls with distance. Supports the chapter's distinction between sound pressure and sound power.

  3. Octave band - Wikipedia - Explains octave and fractional-octave bands, their center frequencies and band limits. Background for the eight-band fan sound data table and the blade pass frequency example in this chapter.

  4. Fan Engineering: An Engineer's Handbook on Fans and Their Applications (9th ed.) - Robert Jorgensen (editor) - Howden Buffalo - Jorgensen's handbook treats speed, size and density changes as one family of similarity relations applied at the same point of rating, the framing this chapter uses for the fan laws and specific speed.

  5. Noise and Vibration Control Engineering: Principles and Applications (2nd ed.) - Leo L. Beranek and István L. Vér - Wiley - Beranek's clear separation of a source's sound power from the sound pressure a listener receives in a room or outdoors underlies how this chapter tells students to read a noise limit.

  6. FanPedia: The Fan & Blower Encyclopedia (PDF) - Twin City Fan - Source for the inlet box and outlet damper statements this chapter quotes (pp. 182 and 187); also available as FanPedia online.

  7. AMCA Publication 201, Fans and Systems - AMCA International - Publication page for the fan application manual that defines system effect, effective duct length and the lettered system effect curves used in this chapter.

  8. ANSI/AMCA Standard 210, Laboratory Methods of Testing Fans for Certified Aerodynamic Performance Rating - AMCA International - Standard page for the laboratory test method that defines installation types A, B, C and D behind catalog ratings.

  9. About Fan Energy Index - AMCA International - Explains FEI and fan electrical power as duty-point metrics, with links to ANSI/AMCA Standard 208, the calculation standard the chapter cites.

  10. ANSI/ASHRAE/IES Standard 90.1 - ASHRAE - Bookstore page for the energy standard that sets minimum fan efficiency requirements at the design point, one of the codes this chapter names as requiring FEI.