Evening star. [volume] (Washington, D.C.) 1854-1972, 1930-10-12
BY H. H. SHELDON,

Professor Of Physics. New York University
- EORGES CLAUDE finally has
succeeded in laying his mile
u long pipe at Matanzas, Cuba,
~ and in generating small
amount of power through util-
izing the difference in temperature be-
tween surface water and that at great
depths. 1t is true that the power gen.
Grated was not large; nevertheless, he
demonstrated a principle. It is con-
ceivable that through refinement he
may get power in commercial proper
tons
To the layman the Claude method
seems to offer great deal of mystery.
II seems contradiction to experience
to generate power by bringing cold
water up from the oceans bottom to
operate turbine. All existing turbines
demand heat for their operation. This
one appears to operate on cold water,
and the colder the better For the mo-
ment let us forget this apparent con-
tradiction and find what it is that
ms61es the steam engine run.
Turbine Improved Water Wheel.
Consider first a water wheel. In its
simplest form it consists merely of a
series of paddles. Water falling from
height strikes these paddles and the
wheel is rotated by the impact of the
water. After it strikes the paddle it is
slowed up as its energy is impaired to
the wheel. The water turbine, with its
curved blades. or buckets as they are
called, Is nothing more than an i'm
proved water wheel. 1t is designed for
maximum efficiency.
Now consider the steam turbine If
we were to build small, light wheel,
like childs pinwheel, and blow steam
ut the fins through small nozzle, the
wheel would turn. In order to blow
the steam through a nozzle it would be
necessary to have the steam at higher
pressure than the surrounding air. This
would normally be the case If the steam
were generated by boiling the water in
q closed vessel and the steam allowed to
escape only through the nozzle. Thus
with pinwheel, simple boiler and a
source of heat we can generate power
The very first steam engines of which
there is any record were of this type.
Low Pressure for Exhaust.
If we attempt to improve this engine
we will develop our simple pinwheel
into the modern turbine. We will per-
haps superheat our steam, and we shall
try to speed up the motion of the steam
by keeping the exhaust side of the tur-
bine at as low a pressure as possible.
We will circulate cold water in the con-
low, and thus lower the pressure.
It becomes evident then that the
prime requisites for the operation Of a
turbine are few. We need q refined
paddle wheel with steam or vapor at a
high pressure on one side and a low
pressure on the other side. If one side
Is hot and the other cold. these pres
sures are then accordingly high and
low respectively without any further
effort on our part.
VapOr Easily Generated.
II one places a pan of water out in
the yard in Summer 1t is a well known
fact that 1t will soon vanish. The water
will not boil away, but vaporize. Mole
cule by molecule 1t leaves the surface
of the water and escapes into the air.
II We place a similar pan of water in
the open during Winter, but at a tenn
evaporate in this same manner.
On a dry Summer day there will be
more evaporation than on dry Winter |
day, but 1t is quite possible that the |
evaporation on dry Winter day may /
exceed that on a humid Summer day. |
1t Is potent, then, that vapor can be |
generated at any temperature and that |
this vapor is different from steam only |
In temperature.
We are now in a position to under |
stand the Claude power scheme At |
the ocean surface at MatanZas Bay the |
temperature of the water is about 80 |
degrees Fahrenheit. This would produce |
small vapor pressure. If the vapor |
thus produced could be run through |
@ low-pressure turbine and into a reSer- |
voir of lower temperature, the turbine I,
should operate.
Condenser Creates Vacuum.
His problem then Is to produce |
low-preSsure reservoir. This he does by |
means Of a condenser, around which Is |
circulated cold water from the ocean |
bottom. Just as in ordinary practice |
we high high temperature, high pres |
sure boiler, a turbine and a condenser, |
50 in the Claude scheme we have a /
low-pressure boiler, a |
turbine and a low-pressure, low-tem- |
perature condenser. It is only the |
scale Of temperatures and pressures |
which are reduced. His boiler is fired |
by the heat from the oceans surface; |
his condensers are cooled by water from |
the oceans bottom
Let us look at the obstacles to the |
success Of the Claude scheme. The |
vapor pressure at 80 degrees Fahrenheit !
Is only about one-fourth of the pressure |
Of the atmosphere. At 40 degrees 1t is !