I have spent many years working towards the completion of this
project. To actually run this so called Otto cycle steam engine.
Now begins the actual proof of concept demonstrations.
What has been learned? First and foremost is how flash steam
actually behaves inside an engine. In theory you may run a great
verity of engine types with flash steam. This includes two cycle
steam engines. In an internal combustion engine there are
significant heat losses. Heat lost from the radiator or
generated from the compression stroke. While experimenting with
flash steam, heat instantly became the primary focus. While
contemplating the heat losses of the IC engine, I wondered if
the same rules of loss would apply to a flash steam engine. What
was found as a result of this speculation is interesting. What
heat would be a lost in an internal combustion engine, becomes a
performance gain with a flash steam engine. So heat generated by
the compression stroke has a discrete advantage. As well as the
reduced firing interval that a four cycle engine accommodates.
Whereas a two stroke configuration (live steam) has a firing
(admission) interval twice that of an Otto cycle engine, for the
same rotations per minute of engine crank-shaft run speed.
Anyone who has actually attempted to supply superheated water to
an engine will realize this helps by a big amount. Since it is
quite difficult to maintain this supply. The current technique
that we use to get this water into the engine is a direct
injection valve. So that every time the spark plug used to fire
(in an Otto engine), now the direct injection valve opens for
the prescribed duration. Which is usually less than a third of a
power stroke from top dead centre. Since in a (very basic) live
steam engine the steam is admitted “the full length of travel”
of the power stroke. However, some more advanced live steam
engines may in-fact feature, what is called “variable cut-off”.
Four cycle (Otto) steam engines are considered intermittent in
nature. “ie” they don’t admit the working medium continuously on
the power stroke. Instead spark-ignition which is similar to,
partial admission is utilized, and expansion is relied upon.
Also, steam can expand farther after the injection duration.
Differing from the chemical reaction of spark-ignition engines.
It was my design goal to achieve a combustion type of reaction
with flash steam. I will be the first to admit that this science
is not easy. It took years of careful experimentation to know
all this. Otto steam engines may be flash steam in nature, or
driven by high-pressure-live-steam and alternately, compressed
inert gasses such as argon.
Flash steam is tricky stuff, so do your homework. Officially
flash steam is only created when water under pressure and heat,
is released to a lower pressure. Which then flashes to cool
itself off. Some will describe throwing water on red-hot, or hot
materials as flashing steam from water. Although this sounds
appropriate its really not flash steam, in the book sense.
Nevertheless both of these mechanisms are used on the Otto Steam
Engine described here. As the L912 Injector releases superheated
water, this water turns to flash steam as it enters the engine,
for one reason only, the inside of the engine has a pressure of
about 125psi. The injector on the other hand is carrying between
2000psi and 700psi, and the water is around 350*f. A positive
displacement pump exerts pressure on the water which is then
heated by the corn burner, then this water is routed to the
injector. Where it enters the engine and flashes to steam, then
the flashed steam is heated further, by the already hot engine
block. The engine block is heated to at least 300*f (in our
case) by the corn burner as well. Depending on the metallurgy of
your piston cylinder arrangement, you may reach higher temps
such as 450*. If you have ever tried to manage such parameters
you will know it’s a thrill a minute. Although it is doable.
Densification
This subject was brought up by a bright individual through
e-mail correspondence. While exploring the viability of the Otto
steam engine, heat engine. Several dynamic tests took place,
these tests included driving the engine with compressed gas at a
pressure of 2500psi. When the engine is run in this mode (CDFC)
heat engine. There are no technical or mechanical configuration
changes made. So instead of supplying superheated (critical)
water (or Hp-live-steam) to the injector assembly, you can
supply compressed gas. And the engine will run this way, with a
high pressure source or pressure tank. The tank pressure starts
at 2500psi and the engine will run down to 600psi or so. Anyone
who has run two stroke engine, or air-motor this way will remark
the engine gets cold. In fact with no heating activated in the
L912 Injector and none being applied to the engine block,
while running a 11hp briggs engine. Ice is observed forming on
the exhaust valve stem (this ice forms from relative humidity).
But the heat generated by the compression stroke kept the block
from getting to freezing temps simultaneously. This tends to
alert me that the Otto cycle is capable of remarkable
efficiencies. While running the engine this way it seemed to run
forever. As a well seasoned mechanic I was stunned to see the
engine run for a half hour or more on a single tank. This caught
me off guard, I did not predict the engine would run so long
from a single tank. Now back to the densification. A question
was asked of me, which do you think is better for the engine
cycle? Heat, Or densification. Lets not forget here that as the
(Otto) engine runs, it is aspiring ambient air. As well as the
injector, adding air to the engine (in this case) “and” the
engine is taking in air through the intake stroke. All these air
sources are coming in contact with the piston during a power
stroke. This is what is being referred to as densification. A
two stroke air motor does not do this, nor does it produce an
internal source of heat from a compression stroke. I am a firm
believer that you have way more to work with thermodynamically,
with an Otto Steam Engine, than with a live steam engine (which
may feature advanced cut-off) or air motor (which does not
feature cut-off).
Applications of engine block heat
As is stated on the “basics” page it is necessary to heat the
engine block for the flash steam engine to operate. In theory if
the engine block is ‘cold’ you could inject a flash steam
discharge into the engine and nothing will happen. Even if the
flash steam discharge was coming from a super-critical source.
Take this example for instance; you could contain water and heat
it to 705ºf develop an internal pressure of 3204psi. Then
discharge it into the engine at TDC, and the piston ‘will not’
be pushed by this discharge. However ‘as’ the engine block is
heated to temperatures in excess of 212ºf a strong reaction
‘will’ occur. And the piston will move downward violently. This
is the type of reaction that’s needed to run an engine. Some
will speculate that as the engine is manually brought through
the cycle (cranked over) it will pick up this heat from the
actual flash steam discharge. Although it is true that a flash
steam discharge will in fact release heat. There is a problem,
the actual mass of the flash steam discharge itself is quite
small in relation to the mass of the engine block assembly. So
you would have to crank the engine over literally for hours to
get the block to an adequate temperature for a reaction (power
pulse). Since we are in fact discharging water that is hot
enough to flash, this is not a cold water injection application.
It has been speculated on the internet by various sources that
an engine cylinder lacks sufficient surface area to evaporate
cold water to steam, I agree. The engine cylinder does lack
sufficient surface area to transform water to steam, ‘in most
cases’. The engine that’s being worked with here, takes care of
the “970 btu wall” with an actual flash steam discharge, and
supplemental block-heating. The flash steam that’s formed is
already steam. Its just being “superheated” by the engine
cylinder and head. However there is a massive technical
conundrum at work here. When the heated water is at less than
the supercritical range. The Btu quantity of the water under
pressure is insufficient, for a 100% transformation to steam
vapor. At best under the most ideal conditions you may get 50%
flash-rates. And since the sufficient btu energy needed, cannot
be stored in the hot-water-under-pressure “itself”, to
accommodate an 100% flash-rate. Another secondary means to add
energy to the reaction MUST be employed. The common methodology
to heat the engine block. Forced hot oil circulation works well
for this purpose. This hot-oil is not under pressure, and may be
circulated in the coolant passages surrounding the cylinder and
cylinder head assembly. So the engine uses two separate heating
circuits, that are both in the fire. One circuit heats the water
for flash steam injection (or live steam generation) and the
other heats the oil that is circulated through the engine
coolant passages.
Summary
The Otto Steam Engine may run on either flash steam or
compressed air or even live-steam. Providing the engine has
suitable robust direct injection technology. As stated before I
was unable to acquire such technology “on shelf” and
Flashsteam.com single handedly developed L912
direct-injection-valves, with Variable Lift for this purpose.
Some may ask why do you call it L912 ?
We started to call the injector assembly L912 back in 1994.
There were several variations of the injector you see today. The
L912 was the best design overall and it became the most workable
unit. And this unit easily accommodated Variable Valve Lift.
Lets dissect the name to understand its REAL origin.
L this denotes liner model (non-rotary valve)
9 this denotes 900 watts of onboard heating
12 this denotes 12 volt direct current actuation
The idea here is to continue the natural evolution of the
Otto cycle engine. Which was truly the most fantastic invention
in human history.
Also to demonstrate that an atmospheric balance in relation
to the Carbon Cycle may be achieved using Corn Burners, for
energy production needs.
Corn Burners
The corn burners seen on this website are very different from
the type used for home heating. These units are industrial
grade. At the beginning of the project corn burners used for
home heating were considered. However the necessity to install
liquid heat exchangers caused some concern. So we started over
from scratch. The first units produced were fully automated.
They would have been suitable for home heating usage. But they
could not accommodate the heat exchangers. The process of
refinement lasted several years. And this was totally separate
from the L912 design process. As you can imagine a lot of work
has been necessary to get to this stage. As stated on the “corn
burners” page the steam engine project (PSTG1) required a very
compact unit. There was no space on the platform for a corn
storage hopper. So the unit was stripped down to the bear
essentials. Which is okay for that unit in particular. All the
corn burners that we work with are very different and unique
from what is currently available. These units do not need a fan
to operate, they will induce the drought they need to operate
correctly without one. However introducing compressed air at low
pressure 5 to 10psi through the J-tube assembly will enable the
unit to melt glass. The performance that we experience with
these units is unprecedented. We just cant say enough positive
things about them. When you hear the “jet engine type roar” this
thing makes, then realize its doing that only with corn, well
its astonishing. And the emissions that are produced are
minimal. There are no noxious fumes, no smoke under all
conditions, and its as cheap to run as we predicted. In fact I
burn corn that the insects have gotten to all the time, little
bit of mold no problem. It just works great. We heat a lot of
mass with this thing and its no problem for it. This is probably
the most rewarding part of the project. In the future I would
like to move into plastics mold injection heating with this corn
burner technology. I am looking for someone to collaborate with
on such a project, preferably recycled plastics. Or even heating
systems for home or large buildings.
