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Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts.

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On Wednesday, January 3, 2018 at 2:48:35 PM UTC-7, mako...@yahoo.com wrote:
> On Saturday, December 30, 2017 at 9:41:08 AM UTC-5, M Philbrook wrote:
> > In article <p20p2r$48g$1@dont-email.me>, nojunk@knology.net says...
> > > 
> > > On 12/27/2017 11:01 AM, tabbypurr@gmail.com wrote:
> > > > On Wednesday, 27 December 2017 16:46:09 UTC, amdx  wrote:
> > > >> On 12/27/2017 1:12 AM, Steve Wilson wrote:
> > > >>> FMurtz <haggisz@hotmail.com> wrote:
> > > >>>> Steve Wilson wrote:
> > > >>>>> John Larkin <jjlarkin@highlandtechnology.com> wrote:
> > > >>>>>> On Tue, 26 Dec 2017 17:54:51 +1100, Sylvia Else
> > > >>>>>> <sylvia@not.at.this.address> wrote:
> > > >>>      
> > > >>>>>>> For reasons I need not go into, I wanted to make a cheap pedestal fan
> > > >>>>>>> blow backwards, by putting the fan on backwards, and running the
> > > >>>>>>> motor in reverse.
> > > >>>      
> > > >>>>>> Wouldn't those two things cancel?
> > > >>>      
> > > >>>>> Many turbine propeller aircraft can reduce their landing roll by
> > > >>>>> placing the propellers in reverse pitch. The blades are still turning
> > > >>>>> in the same direction, but the thrust vector is reversed. They are not
> > > >>>>> very efficient in this mode, but are still able to slow the aircraft.
> > > >>>    
> > > >>>>> To visualize what would happen in a pedestal fan, imagine turning it
> > > >>>>> around 180 degrees. The motor is still spinning the propeller in the
> > > >>>>> same direction, but the thrust vector is reversed in relation to the
> > > >>>>> floor.
> > > >>>    
> > > >>>>> In order to reverse the thrust vector, either the propeller pitch has
> > > >>>>> to be reversed, or the motor has to be reversed.
> > > >>>    
> > > >>>>> John is right. Doing both would cancel.
> > > >>>    
> > > >>>> Wrong,reversing motor would reverse air flow, reversing the propeller
> > > >>>> would be same air direction but would put the leading edge in the right
> > > >>>> position for efficiency.
> > > >>>
> > > >>> Wrong. Think about it. Reversing the propeller pitch reverses the thrust
> > > >>> vector. This is how turbine aircraft shorten their landing roll.
> > > >>>
> > > >>>
> > > >>    OK I took the cover off a 3 blade fan that turns clockwise. I removed
> > > >> the blade put it on backwards. The fan still blows air in the same
> > > >> direction. It doesn't blow very much air though.
> > > >>    Certainly is some design consideration in the way the blade is curved.
> > > >>                                               Mikek
> > > > 
> > > > so if you then also change the motor direction, you get reverse flow with good efficiency. It's ain't rocket science, it's fan science.
> > > > 
> > > > 
> > > > NT
> > > > 
> > 
> > I am glad you Rocket experts aren't talking about centrifugal 
> > impellers..
> > 
> > ;)
> 
> next topic, why does swapping I and Q cause a spectral inversion?
> 
> :-)
> 
> mark

Or why my '72 Dodge Dart had so many left-hand connections.  According to this thread I must have just had my nuts on backwards!

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OT: Running a pedestal fan in reverse - failed - a rant of sorts. Sylvia Else <sylvia@not.at.this.address> - 2017-12-26 17:54 +1100
  Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Rheilly Phoull <froggins@iinet.net.au> - 2017-12-26 19:29 +0800
  Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. mpm <mpmillard@aol.com> - 2017-12-26 04:49 -0800
    Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Sylvia Else <sylvia@not.at.this.address> - 2017-12-27 09:52 +1100
  Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. tabbypurr@gmail.com - 2017-12-26 06:07 -0800
    Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Sylvia Else <sylvia@not.at.this.address> - 2017-12-27 09:58 +1100
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. mpm <mpmillard@aol.com> - 2017-12-26 18:52 -0800
        Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Sylvia Else <sylvia@not.at.this.address> - 2017-12-27 14:57 +1100
  Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. John Larkin <jjlarkin@highlandtechnology.com> - 2017-12-26 10:21 -0800
    Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-12-26 11:48 -0700
    Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. rickman <gnuarm@gmail.com> - 2017-12-26 14:03 -0500
    Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. John S <Sophi.2@invalid.org> - 2017-12-26 14:31 -0600
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2017-12-26 15:44 -0500
        Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. John S <Sophi.2@invalid.org> - 2017-12-26 15:06 -0600
        Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. John S <Sophi.2@invalid.org> - 2017-12-26 16:16 -0600
        Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. John Larkin <jjlarkin@highlandtechnology.com> - 2017-12-26 17:26 -0800
          Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Sylvia Else <sylvia@not.at.this.address> - 2017-12-27 14:42 +1100
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. not@telling.you.invalid (Computer Nerd Kev) - 2017-12-26 21:00 +0000
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. rickman <gnuarm@gmail.com> - 2017-12-26 18:37 -0500
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. "David Eather" <eather@tpg.com.au> - 2017-12-27 09:48 +1000
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. FMurtz <haggisz@hotmail.com> - 2017-12-27 15:57 +1100
    Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Sylvia Else <sylvia@not.at.this.address> - 2017-12-27 09:50 +1100
    Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. whit3rd <whit3rd@gmail.com> - 2017-12-26 18:55 -0800
    Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Steve Wilson <no@spam.com> - 2017-12-27 05:40 +0000
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. FMurtz <haggisz@hotmail.com> - 2017-12-27 17:24 +1100
        Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Steve Wilson <no@spam.com> - 2017-12-27 07:12 +0000
          Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. FMurtz <haggisz@hotmail.com> - 2017-12-27 18:40 +1100
            Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Steve Wilson <no@spam.com> - 2017-12-27 12:34 +0000
              Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. FMurtz <haggisz@hotmail.com> - 2017-12-28 00:36 +1100
              Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. rickman <gnuarm@gmail.com> - 2017-12-27 17:59 -0500
          Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. krw@notreal.com - 2017-12-27 09:39 -0500
          Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. amdx <nojunk@knology.net> - 2017-12-27 10:45 -0600
            Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. tabbypurr@gmail.com - 2017-12-27 09:01 -0800
              Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. amdx <nojunk@knology.net> - 2017-12-27 12:34 -0600
                Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. rickman <gnuarm@gmail.com> - 2017-12-27 18:03 -0500
                Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. tabbypurr@gmail.com - 2017-12-27 15:18 -0800
                Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. amdx <nojunk@knology.net> - 2017-12-28 09:18 -0600
                Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Sylvia Else <sylvia@not.at.this.address> - 2017-12-28 12:38 +1100
                Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. M Philbrook <jamie_ka1lpa@charter.net> - 2017-12-30 09:41 -0500
                Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. makolber@yahoo.com - 2018-01-03 13:48 -0800
                Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. DemonicTubes <tlackie@gmail.com> - 2018-01-03 14:08 -0800
                Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Tauno Voipio <tauno.voipio@notused.fi.invalid> - 2018-01-04 15:18 +0200
            Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Sylvia Else <sylvia@not.at.this.address> - 2017-12-28 12:36 +1100
          Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Jasen Betts <jasen@xnet.co.nz> - 2017-12-28 06:36 +0000
            Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Phil Allison <pallison49@gmail.com> - 2017-12-28 00:16 -0800
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Phil Allison <pallison49@gmail.com> - 2017-12-26 22:38 -0800
        Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. krw@notreal.com - 2017-12-27 09:40 -0500
  Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Sylvia Else <sylvia@not.at.this.address> - 2017-12-27 15:02 +1100
    Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Sylvia Else <sylvia@not.at.this.address> - 2017-12-27 18:11 +1100
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. FMurtz <haggisz@hotmail.com> - 2017-12-27 18:42 +1100
      Re: Running a pedestal fan in reverse - failed - a rant of sorts. "P E Schoen" <paul@pstech-inc.com> - 2017-12-27 03:17 -0500
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. tabbypurr@gmail.com - 2017-12-27 01:59 -0800
        Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Sylvia Else <sylvia@not.at.this.address> - 2017-12-27 21:29 +1100
          Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Tauno Voipio <tauno.voipio@notused.fi.invalid> - 2017-12-27 14:24 +0200
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. krw@notreal.com - 2017-12-27 09:43 -0500
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. John Larkin <jjlarkin@highlandtechnology.com> - 2017-12-27 11:25 -0800
        Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. tabbypurr@gmail.com - 2017-12-27 11:32 -0800
        Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Jasen Betts <jasen@xnet.co.nz> - 2017-12-28 06:20 +0000
    Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. amdx <nojunk@knology.net> - 2017-12-27 10:50 -0600
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. FMurtz <haggisz@hotmail.com> - 2017-12-28 14:49 +1100
        Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. FMurtz <haggisz@hotmail.com> - 2017-12-29 11:34 +1100
    Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. bloggs.fredbloggs.fred@gmail.com - 2017-12-27 10:22 -0800
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. Sylvia Else <sylvia@not.at.this.address> - 2017-12-28 09:41 +1100
        Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. bloggs.fredbloggs.fred@gmail.com - 2017-12-27 15:29 -0800
      Re: OT: Running a pedestal fan in reverse - failed - a rant of sorts. rickman <gnuarm@gmail.com> - 2017-12-27 18:40 -0500

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