On Fri, Jul 15, 2016 at 10:55 AM, Poul-Henning Kamp <[email protected]> wrote:
> -------- > In message < > cany2ixq6onvridofgnfkebqjdkntp7t8kue7boupxjwlcux...@mail.gmail.com> > , "William H. Fite" writes: > >David Kirkby scripsit: > >> > >> I often here of people replacing fans with quiter ones, but I suspect > that > >> all they really do is reduce the airflow. > > > >Not necessarily, Dave. The Austrian company, Noctua, for one, makes > >extremely quiet fans with excellent airflow. > > ... at zero pressure differential, which is easy to do (Think: ceiling > fan). > > Right. You have to look at the curves on the data sheet that shows air flow vs. static pressure (and be careful about the static pressure scale). I found that a 'quiet' fan would often be flowing one tenth as much air as the original fan at the static pressure at which the original fan was rated. In a given instrument, you may get away with the quieter fan, but how would you tell other than putting a thermometer inside and making a before/after comparison? Orin. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
