Re: Electric vs mechanical fans

Balamurugan J. (JB@rect.ernet.in)
Sun, 27 Apr 1997 19:16:35 IST+530

I certainly do agree that the electric fan is of unequalled value in
slow moving traffic, such as in urban traffic. But it certainly is
not as efficient as the electromechanical or thermoclutch fans, as
far as power loss is concerned.

jb

>
> I've been following the discussion over electro-magnetic clutched vs
> other fans. I'm using both at the moment. I have a pair of 14 inch
> electrics on my Chevy truck and the electro-clutch on my 82 505 TD. I
> think the electrics are far superior for 2 reasons not yet mentioned.
> Number one, they're independent of engine RPM, working far better than
> anything mechanical when you're stuck in slow or non-moving traffic. No
> mechanical fan is going to run max RPM when you're idling... the
> difference in my truck in traffic is astounding. Number two, electric
> fans are not coupled to the engine and so they don't have to accomodate
> engine movement; they are extremely closely shrouded making them much
> more efficient. My 505 TD has been modded for the lightweight fan, but
> still I have to allow the 1 inch gap around the fan blades for possible
> engine movement. If you ever run a smoke test thru the air stream when
> the fan is engaged you might be surprised at the wasted airflow and
> turbulence. I've seen it done on aircraft engines with "ducted" fans
> (shrouds) and the effect on airflow is nothing short of phenomenal!
>
> My money's on electrics and I'll do it to the 505 soon as I figure out
> what to do with the crazy mag clutch and bearing assy. I believe it
> would provide an opportunity to double-belt at least the alternator and
> water pump, providing badly needed redundancy in those areas. Shame on
> French engineering for putting the most important belts at the BACK of
> the belt cluster!! They'd never get away with that in aircraft.
>
> ______________________________________________________
J.Balamurugan Phone: +91 (431) 552281
Computer Support Group FAX: +91 (431) 552133
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