[Stoves] Variable Speed Stove Fan SIMPLIFIED

[Peter Singfield]

At 09:38 PM 12/4/2006 -0500, you wrote:
>Hi Kevin,
>
>Yes, I've been doing some of the math with Hp (33,000/ft) and I agree it
>adds up to a lot of water being lifted.
>
>Just a few watts add up to a huge amount of work! In our modern world, how
>do we ever generate all this energy.............
>
>
>Jeff
>

Both Kevin and I have been there and done this same energy discussion on
one of the lists a few years back. And the resulting discussion on just how
energy dependent we all are -- when you really look at the "measures" of
energy -- as you have just been presented with in this case.

So -- how to make an very economic source of energy with the parts and
pieces at hand??

Maybe by "value" adding??

How about an Atmospheric engine?? Which is as good a potable water
distiller as you can get -- plus kicks out some energy as a bonus??

A very low pressure (Typical 5 PSI) portable waster generator attachment --
boils water -- then condenses it. Only you condense it using a "Newcomen
Atmospheric Engine" --

http://www.keveney.com/newcommen.html

Now use your creative instincts --

Water jacket ringing around top of stove -- no big deal there -- 

Steam so evolved flows under 5 psi pressure to Newcomen engine.

As your dealing with low temps ( 5 PSI saturated = 227 F -- and always
(unless you try this at the bottom of a very deep mine shaft) one can
probably adapt a common bicycle air pump as the working cylinder -- and no
need for a crank either -- just have the reciprocating motion operate a
"bellows" -- ya don't need high tech to blow air folks!!

You can design a very simple accumulator to smooth out the bellow pulses --
right??

Say a small bucket up side down in a bigger one filled with water ---

Or -- attach a second bike pump to it -- and that should get you at least
10 PSI pressure to pump up an old patched up car tube -- and you then can
bleed out through a small orifice a small high velocity stream of air.

Most stovers would be happier to have a little extra pressure small blow in
exactly the right spot -- rather than a low pressure breeze over everything
-- right folks??

The thing is the cost is covered by the dual purpose of this device -- it
produces distilled water -- pure water -- very potable water. The
relatively small amounts so produced is a life saver for babies -- as example.

See appended #1 for the technical description of theory of operation --

For this application one could run even lower pressures -- and no need for
that auxiliary pump -- one could then indeed hand lift "potable" water for
the water squirting condensing cycle.

Moving along either further ahead in "time" -- take a look at the
grandfather of all steam engines.

Ok -- have some real entertainment for a change -- and read all about this
fascinating subject at:

http://inventors.about.com/od/wstartinventors/a/james_watt.htm

Full of information such as this line:

"James Watt first made a cylinder of nonconducting material -- ­wood soaked
in oil and then baked and increased the economy of steam" 

There you go Jeff -- a wooden steam engine -- what more could one want -- eh??

Stovers -- wooden steam engines to blow your fires with -- eh???

Anyway -- the history of James Watt at that Url above will certainly be an
extremely enjoyable read for many on this list -- and especially in these
depressing times -- so enjoy -- eh??

Never forget the advantage we have -- modern materials --- when you read it!!

There should be many the brain wave attack there to ---

Peter/Belize

>Kevin wrote:
>> 1 Watt = .101 kilogram-meter per second
>>
>> Assuming 100% efficiency of your turbine, then for each watt of fan power,
>> you will require .101 kg of water to fall through 1 meter.
>>
>> If the waterwheel efficiency was 50%, then you would need .202 kg of water
>> flow per second for each watt of shaft power output to the fan. Each
>> minute
>> would require about 12 kG water flow; each hour will require lifting about
>> 720 kG of water a distance of 1 meter
>>
>> If you require 3 watts of power to drive your fan, you would need to lift
>> about 2160 kG water per hour.
>>
>> The system would work, but it would be tedious.
>>
>> Best wishes,
>>
>
>

**********appended 1***********************

This magnificent engine was patented in 1705 by Thomas Newcomen, and is
generally regarded as the first 'modern' steam engine. Unlike later steam
engines, the Newcomen works on the atmospheric principle. 

The Newcomen was first used to pump water from mines in England.  The pump
rod at left is coupled to the driving piston by a large rocking beam.
 
Water is boiled continuously to produce steam.  During the piston's upward
stroke this low pressure steam (about 5 p.s.i.) is admitted to the
cylinder.  The pressure is insufficient to lift the piston on its own --
the weight of the pump rod does most of the work.
  
At the top of the stroke the steam valve is closed and a water jet is
briefly turned on, cooling the steam in the cylinder.
  
The cool steam contracts, sucking the piston downward.  ...Or stated
another way: the higher atmospheric pressure drives the piston downward,
hence the name atmospheric engine.  At the end of the stroke, the cooling
water is drained from the cylinder by an extra passage not illustrated
here.   
During the upward stroke, an auxiliary pump fills the cooling water reservoir.
  
Newcomen engines were successful in part because they were very safe to
operate.  Since the steam was under such low pressure, there was no risk of
a dangerous boiler explosion. 

As near as I can tell, the earliest Newcomen engines featured manually
operated valves, as illustrated here.  An operator apparently stood on a
platform near the cylinder base and threw the valve levers on each stroke.
(From the illustrations I have available, this engine seems to have stood
at least 20 feet tall).  Later Newcomen engines featured automatic valves
which were coupled to a pushrod attached to the main beam.