[Gasification] OT - two stroke engine -- now four stroke

[Peter Singfield]

>
>Sure, but how are you going to get another stroke?  Won't you need  
>144.6 btu to get the steam back into the boiler?
>

Hi Bob;

First -- some errors need correcting:

> One pound of water at 300 PSI and 600F is well "superheated"
>
> Volume/density of steam is 1.0723 ft cubed.
>
> Total "heat" per pound of steam in this state = 1351.1 btu

Wrong -- 

300 PSI and 600F  "superheated" steam has:

V = 2.005
h = 1314.7

and

> OK -- now we have 2.145 feet cubed of steam --
>
> Well -- 220 psi at 400 F --- and a btu value of 1206.5
>
> 1351.1 - 1206.5 = 144.6 btu "difference"

no longer applies --

Rather: 

334.77 F at 110 psi does

V= 4.085
h= 1188.9

So -- energy difference between these two states of steam 

1314.7 - 1188.9 = 125.8 btu 

Not 144.6 btu

But -- to answer your question --

Of course your right -- 

Combined gas law:

P1 * V1/T1 = P2 * V2/T2

As in this model the engine/cylinder is well insulated -- that formula has
to hold true -- and any energy extracted from the expansion stroke is equal
to the energy required to re compress it.

I actually am working on a four stroke steam design -- more on that later.

But "compression" is the huge problem.

Funny thing is -- in Uniflows they found that compression of steam in that
specialized cycle actually improved engine efficiencies. That is well
documented.

You know -- the Uniflow design is a straight through one -- steam in the
top through a short cut-off -- then piston down on power stroke -- exposing
exhaust ports at bottom stroke -- condenser vacuum voiding the cylinder --
but some steam staying behind -- of course.

They found that by reducing the clearances for the swept volume return
stroke as much as possible -- thus creating high compression ratios at top
dead center -- when the new charge of steam was introduced -- greatly
improved engine efficiency performance.

Yet by all the Gas "laws" -- this makes no "sense"!!

What is really going down??

The four stroke steam engine -- diesel engine conversion -- add in an
exhaust stroke -- and an intake -- and the regular compression stroke
pushes steam into a flash heating boiler -- greatly super heating the
original low quality steam from the first intake stroke -- hopefully in an
attempt to raise those normally so dismal engine efficiencies associated
with small piston steam engines running low quality steam.

High quality steam is terribly difficult to produce -- starting with the
high pressure feed injection then required -- and finishing with deadly
high pressure boilers.

KISS might be in a four stroke steam engine converted from an existing
small diesel engine.

I'll explain more later -- 

The "laws" say -- basically -- you double the pressure -- you double the
temperature.

Please -- anyone -- correct me if I have that thought wrong??

Right now I see but one way to get around that problem -- emulate the
uniflow -- and compress back against a below atmospheric charge of steam --
keeping clearances low -- compression ratio high -- but no excessive
compression temps -- else the super heater mid stroke can't work ---

More on this mind twister later --

Peter/Belize