Improvements in Steam Engines.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improvements in Steam Engines.
1, FELIX ALEXANDRE TESTUD DE BEAUREGARD of 162 Rue Lafayette, Paris
in the Republic of France, Engineer, do hereby declare the nature of this invention
and in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
1st. The supply of energy or mechanical power which an engine possesses is
estimated by the length of the calorific scale passed through--this is called the fall
of pressure for saturated steam and calorific fall for unsaturated steam. At the
present time steam engines are working at between 4 and 6 kilogrammes which
corresponds to the thermometric figures of 151 and 164 degrees centigrade. Taking
5 kilogs. as an average, that is 158° therefore the fall of pressure in non-condensing
engines (steam being rejected at 100°) is 58°; and for condensing, engines which
have a vacuum of up to 60 to 70 centimeters (the steam corresponding to 45
and 60°) the fall of pressure increases from 40 to 55°. Hence it results that the
complete engine with vacuum and pressure only works through a range of 103
to 118 degrees centigrade.
2. The combination herein described adapted to all kinds of engines worked by
an expansive fluid and not being dependent upon the expenditure of the said
machine, any reduction which it makes in expenditure is the same whatever kind of
engine may be employed. This economy may be stated to be about of the
expenditure of any machine the fall of califoric varying between 350 or 400° to 40°,
that is 310 to 360 degrees centigrade.
3. The use of the aspirator (apparatus patented by me in the year 1860); for
exhausting on one side, compressing on the other, to take back the exhaust steam,
which in the ordinary way of working opposes its elasticity to the energy of the
motor steam. This opposition is entirely avoided for the steam being drawn away
by the aspirator is thrust into the positive side where it regains its lost energy and
immediately becomes working steam; and this is not all. In this change of state,
it also undergoes a molecular change acquiring properties of elasticity and energy
For this reason I
which are not found in either saturated or unsaturated steam.
rightly or wrongly call this new fluid ponderable caloric; it is a compound of very
little water and of much heat and ponderable, because it is elastic and produces
force which moves the piston of the engine. The above feature is therefore
entirely novel, none having thought of employing this apparatus for obtaining a
like result.
4. The aspirator is the principle part of the cycle, it is this apparatus which
gives the movement to the piston. This movement derived from the elastic force
of steam is largely regained by the compression in the injector cones changing into
sensible heat part of the latent heat which in the formation of motor steam
represents the greater part of the cost. which has to be, incurred. From which
there results economy of fuel together with an increase of primordial energy
resulting from a better and novel use of the heat expended.

page_text: 5. From the above it can be easily seen that the collection of the exhaust steam
(negative steam) being proportional to suctional power of the aspirator apparatus,
the said exhaust steam can be brought back to its point of formation say 100° in
the apparatus called the coefficient but on the other hand in bringing the steam to
its point of formation, you lose all the sensible heat which it still had at its exit
from the cylinder. This loss is greatly lessened because the motor piston has
opposed to it no pressure greater that the atmospheric pressure. Such results were
obtained by my first cycle. They were encouraging, I went further; increasing the
suctional power of the aspirator. The experiment did not answer my expectations
for if on the one hand I gained under the piston on the other hand I lost upon the
collection of the exhaust steam because of the decrease in temperature of this latter,
I made this experiment more especially with a view to navigation. Indeed the
vacuum under the motor piston plays an important part in river and sea navigation,
condensing being easy and costing little. For this application it was losing much
to reject a power always proportional to the power of the engine and acting with
so little expense. It is in view of these considerations that the second cycle
(calorific cycle) was made, for once the negative steam is condensed, there was no
longer anything useful to take, the resulting liquid being itself lowered to 40°.
. 6. I have raised the normal temperature of the primordial motor steam, I have
superheated, and desaturated the steam obtaining by this an important economy of
latent heat hitherto lost. It can easily be understood that this becomes of extreme
importance and allows us to introduce a new apparatus (the No. 2 boiler) for the
generation of steam without a separate fire and consequently an entirely new
economy 1. Escape of the gaseous products of combustion at very low tem-
perature (a few degrees above the steam). 2-formation without cost of steam
under high pressure; in a word the production of energy without cost. In addition
to the above wherever heat is radiated the heat given out is usefully collected.
(3rd cycle, feeding cycle). When water is distilled (the only method of obtaining
it pure) this water is limpid and completely without colour (be the steam saturated
or unsaturated) that which we recover, obtained by this combination is milky and
lighter than distilled water, its ebullition point is under 100° and by chemical
additions I have several times found traces of ammonia and alcohol. The fluid
used in my three cycles is therefore not the same as steam but a new fluid.
I have called this new fluid ponderable caloric because it acts mechanically upon
the motor piston. Experiments often repeated have shewn me that this change of
nature in the steam was due to the molecular expansion taking place under the
spontaneous differences of temperature, and speeds of exhaust in one medium from
which it results that to obtain a real diagram of the motor force with which the
motor piston is moved, the tube which transmits the expansion to the measuring
apparatus should be constantly heated in order to maintain in the fluid, which
traverses it, an expansion equal to that which it has in the motor cylinder-and
any diagram drawn without this preliminary precaution will not give the true power
obtained.
In order to understand what follows I will describe and show the object of each
of the apparatus forming part of the three cycles. At the commencement of this
Specification I said, under a vacuum of 60 there is no steam to take which is
mechanically useful; from this fact, the invention of my second cycle called
calorific cycle, having for object the collection of heat. Having no longer any
force to take, I employ apparatus collecting the heat and with this heat I have
gained the force. The first collection of heat expended takes place in an apparatus
which I call recuperator. It has for object as will be seen further on to take up
the sensible and latent heat contained in the steam after its mechanical work
(exhaust steam).
This apparatus is simply a tubular receiver of very small sections made of good
heat conducting metal. It is made so as to contain relatively little liquid and
causes the fluid which traverses it to take a long course. The construction is novel
because it is the result of a calculation based upon experiments leading to the

page_text: attainment of a new result. This fact will prove it:-In its normal travel the
steam or rather the exhaust fluid is thrust into a vacuum of more than 70 centi-
meters losing the greater portion of its sensible heat and all its latent heat by.
the spontaneous condensation which takes place, this fact entirely to the profit of
the surrounding liquid, which under a vacuum of 40 centimeters produced by an
aspirator transforms this heat into elastic fluid which is thrust by the said exhauster
into the return circuit. Therefore in reality under a vacuum of more than
70 centimeters, we obtain a new mechanically useful expansive force.
This expansive force, either latent in the form of liquid under pressure, or sensible.
in the state of steam, is placed by the aspirator into another apparatus which
increases its energy tenfold; the boiler No. 2 or second recuperator invented and
constructed to take up all the heat hitherto lost in the gases produced by
combustion.
Now that these apparatus are described, I will show the method of working.
The motor boiler is under pressure ready to allow the fluid which it contains at
the temperature of 350 to 400° centigrade to escape.
Note. This temperature which a priori appears excessive, time study and
experiments have shown to be useful and very economical, latent absorbtions being
diminished two thirds by this fact; and is now practicable owing to asbestos having
replaced vegetable fibre in glands and stuffing boxes.
The boiler No. 2 (negative boiler) is also under a pressure which differs by less.
than half a kilogramme from the positive motor boiler.
The engine and the whole portion of the apparatus which acts by the fall of
pressure being in a cold state. The admission valve is opened, and at each stroke,
the fluid escapes towards the exhausting side of the closed cycle. Why is it
exhausting this side? Because it comes into the coefficient which in engines
working with a vacuum plays the part of cooler, I do not say condenser, it will be
seen further on why. The circuit is established by a return pipe starting from the
coefficient to lead into the suction pump called either air or vacuum pump whose
delivery thrusts the fluid into the heat recuperator.
On commencing to work the air pump draws the exhaust fluid or steam of the
coefficient to send it into the heat recuperator, which steam or fluid condenses in
giving to the already heated water of the apparatus (by the passage of the fluid in
the conductor tubes) both its sensible and its latent heat. Each stroke of the
engine piston augments the amount of heat stored up in the water, transforms it
into steam which is simultaneously taken out by the aspirator and is by this latter
placed into the recuperator No. 2. (boiler).
Here the aspirator plays two parts which do not lack interest. 1. Diminution of
more than half the work of the air pump. 2. Bringing out all its heat (sensible'
and latent) to the boiler No. 2.
Note. Experience has proved that in view of economy, and the homogeneousness
of the combination it is preferable to take liquid saturated with caloric in preference
to steam, compression being effected in the boiler No. 2 under a pressure greater
than that which works the motor aspirator. Things taking place thus all the time
of working; such is the steam cycle, the first cycle.
When the indicator shows a vacuum in the coefficient greater than 40 centimetres
this cycle loses a great part of its importance, there only being in the coefficient a
negative hygrometric steam without real utility in the sense of mechanical power.
After a time the second cycle dominates, the calorific cycle transforming the
heat stored up in the liquid of the recuperator No. 1 into live power, and energy
which as we have said above, carried forward into the recuperator No. 2 increases
its force tenfold in a palpable form (pressure) to again bring its (the liquid's)
energy to the motor cylinder from whence it has just come deprived of its energy.
Third cycle. As has before been explained, the recuperator No. 1 from this
moment plays the part of a condenser by depriving the exhaust steam of all the
heat it contains. To take into account the amount of energy produced each
moment by this apparatus remember that the motor fluid has a sensible heat of

page_text: nearly 400°, also remember that the energy of a fluid is proportional to the sensible
heat which pervades it.
This also explains its power of expansion at admission and the increase of sensible
heat still remaining in the exhaust fluid, that is to say after accomplishing its
useful work on the one hand, and on the other the sum of the caloric which it takes
away to abandon to the profit of the whole, after passing through the passages of
the recuperator No. 1.
On leaving the apparatus the fluid being deprived of its heat, has rebecome liquid
which drawn by the suction of the air pump is thrust by it (or by the feeding pump)
into the recuperator No. 1 (or into the positive boiler) that is to say into the circuit
for again recommencing its incessant circle.
In finishing this explanation I may add that the first cycle (steam cycle) preserves
all its importance, when engines working under atmospheric pressure are in question,
the coefficient working with boiling water, that is having no other regeneration of
refrigerated water than that which is brought about by evaporation. In this
case, the coefficient works with closed covers in the manner shown for the
recuperator No. 1 in the working in the first moment that is to say as apparatus
collecting the lost heat; in fact at this temperature and without vacuum there
cannot be question of condensation.
Summary of the working. 1st. In the case of working by the first cycle, under
the atmospheric pressure, continual and direct regain of considerable quantities of
exhaust steam of small temperature by the calorific cycle (recuperator No. 1).
2. In the case of working under vacuum, diminution of the direct regain of steam,
in proportion to the formation of this vacuum, but proportional increase in the
collection of heat in the recuperator that is to say, equality in the definite collection
but gain in the utilisable motive power from the vacuum formed (whatever it may
be) in the coefficient.
3. As to the third cycle (liquid) its utility and its contingent economy remains
invariable.
DESCRIPTION.
Sheet 1. Theoretical plan of a machine moved by the three united cycles.
A B C the whole of a complete engine (whatever may be the type) consisting of:
A cylinder and slide valve. B feeding pump. C air pump D recuperator No. 1
(see description and drawings of Sheet II). E coefficient equilibrium (see Sheet 4
for its peculiar construction). F recuperator boiler No. 2 having no separate fire.
Collector of unutilised heats passing from the superheater. G H superheater.
G the portion reserved for the negative steam H. the portion for the positive steam
(see details Sheet III and description of this sheet). I positive motor boiler.
Jaspirator motor (mixer of the two steams sec Sheet V and description) L aspirator
taking either the liquid, or the steam of the recuperator No. Í to place it in the
boiler No. 2.
Note. Each of the apparatus D E F. GHI, J and L (motor boiler,
recuperators Nos. 1 and 2, coefficients and exhausters) are of varying sizes
according to the power of the engine. This variation may be obtained by enlarge-
ment or by the multiplication of the apparatus.
a pipe leading the motor steam to the superheater H. b pipe leading the positive
superheated steam to the motor aspirator J. C pipe leading to the slide valves of
the engine, the mixture of the two steams which has become the fluid called
ponderable caloric. d exhaust pipe of the engine communicating with the tubular
system of the recuperator apparatus No. 1 marked D (see details Sheet II).
ee diagrammatic representation of the said tubular system. pipe joining the
recuperator No. 1 to the coefficient E. yy diagrammatic representation of the
interior of the coefficient (sec details Sheet IV). h the pipe going to the air
pump C. i pipe connecting the air pump delivery to the recuperator No. 1.
liquid surrounding the tubular system cooling the exhaust fluid. 1 pipe con-
necting the recuperator No. 1 to the boiler No..2. This pipe takes freely either

page_text: the steam formed in the recuperator No. 1 or the liquid contained in it, to pass it.
into the boiler No. 2. This circulation takes place because of the aspirator L
which by means of a small portion of positive 'superheated steam produces a vacuum
of 40 centimetres relieving the work of the air pump and bringing under pressure
the negative boiler F (to understand the effect produced by this employment of
positive steam see description of the working at time of starting). m pipe for the
negative steam (then under pressure) to the portion G of the superheater, to let it
regain thermometric elasticity (superheated desaturation). n pipe leading the
negative superheated steam to the back of the motor aspirator, to again form the
new expansive fluid and to again give the piston its motion.
Feeding cycle.
return for condensed liquid to the coefficient (by means of the feeding pump).
8 s¹ return for the said liquid, either into the recuperator No. 1 by the paths, or
into the positive boiler by the path s¹ to again form one or other of the two steams
and after accomplishing work again condensing and indefinitely continuing (loss
excepted) its incessant cycle. steam pipe for the motor steam working the
aspirator L.
Order of the cycles.
It is sufficient to indicate by the same letters in the annexed diagrammatic plan
the travel of fluid in each of the cycles to easily understand the use of each of them
and the economy obtained by the whole combination.
Beginning at the motor boiler I, we find
1. For the steam cycle, the following closed path: pipe a, superheater H pipe b,
aspirator J, pipe c, engine A, pipe d interior system ee of the recuperator No. 1,
pipe f, interior gy of the coefficient pipe h, air pump C, pipe ij first heating by
contact in the recuperator No. 1, 7 second heating caused by positive steam of the
aspirator L. F boiler No. 2 causing third heating and definitely forming the
negative steam, pipe m, desaturation and superheating of this negative steam in G,
pipe n, aspirator passage J and mixture of the negative regenerated steam with a
portion of positive steam to recommence its useful work under the motor piston.
2. The calorific cycle. This cycle is the same as tlfe steam cycle as far as
recuperator No. 1.
There leaving the said steam cycle to continue its large
circuit takes back directly by contact the heat (completely or partially according
to the vacuum produced in the coefficient) to return it by the tube into the
boiler No. 2, reuniting the whole of the hitherto lost collected steam to form
negative steam. After the two cycles proceed simultaneously to be at J finally
regenerated by means of positive steam.
3. For the hydraulic cycle (feeding). See its path by the above description.
Letters s s¹.
Note. On the delivery pipe i of the air pump there is a valve by which air
which has found un entrance through imperfect joints can be allowed to escape.
This valve, being open to the air, stops if wanted the working of the first steam
cycle. In this case the condensed feed liquid may be taken into the coefficient and
sent after aeration into a tank from which it is taken by the feeding pump (change
of path of the 3rd cycle, easy to understand and not altering in the slightest its
economical working). The steam cycle being in this case eliminated, the work of
the feed pump is considerably lessened, no longer having to draw against a vacuum
of 70 centimetres of mercury.
Sheet II recuperator No. 1 (D in the diagrammatic sketch). The letters used
correspond to the same letters in Sheet I.
d is the entrance for the exhaust fluid. ee tubular system in which the said fluid
passes. outlet of the fluid cooled by contact. j surrounding liquid for taking
up the heat.
return of heated liquid, return of steam formed. (These two
last pipes lead into the aspirator L diagrammatic plan). return for steam ejected
from the air puiip. s feed passage.
The apparatus is constructed like a low pressure multitubular boiler, having

page_text: tubes of small diameter, and provided with accessories such as-M steam gauge,
N gauge glass, S safety valve.
Sheet III recuperator No. 2 called boiler No. 2 and superheater.
Letters corresponding to the same letters on Sheet 1.
G is the portion of the superheater for the desaturation of the negative steam.
H portion of the superheater for the calorific supersaturation of the positive steam.
Zinlet for the collection of heat from recuperator No. 1 (liquid or vapour). m out-
let for the negative steam under pressure. outlet for the negative superheated
steam. a inlet for the ordinary motor steam proceeding from generator I. outlet
for the positive superheated steam.
Letters only concerning the special construction of the apparatus.
cash pit. fire bars. ee openings made in the arch of the grate letting out the
products of combustion then at a high temperature: The solid portions of this
arch are vertically below the superheated tubes, and so place these latter in shelter
from the too great radiating intensity of the furnace. first heating chamber
gg passage for the burning gases into the second heating chamber. Openings in
the vertical partition acting upon the superheating tubes of the 2nd chamber in
the same manner as the horizontal openings ee formed in the furnace arch.
second heating chamber moderate superheater, copper superheating tubes i i
utilisation on the exterior of the boiler No. 2 of the heat contained in the products
of combustion, (heat hitherto wasted). jj interior tubular system (copper)
collecting the surplus hot gases coming from the superheater and only allowing
them to escape at twenty degrees above the temperature of the steam produced
in the said boiler No. 2. chimney for the outlet of the gases then at a low
temperature. copper superheating tubes. 2nd heating chamber.
s iron super-
heating tubes Ist heating chamber. tt special unions between the superheating
tubes, for facilitating the removal of tubes rendered defective by use. u a' tubes
uniting the copper superheater with the corresponding iron portions. m² n¹ non-
superheated steun pipe joining the motor aspirator and making it possible by
turning cocks placed in its course to shut off one or both portions of the super-
heaters (copper or iron) or at need both for urgent repairs without stoppage of the
working.
Note. (The same arrangement is made for the positive superheated portion).
It results from this arrangement that the final temperature of the fluid can be
arranged by the driver of the engine, who may by opening the valves, mix the
ordinary steam in varying quantities with superheated and consequently increase or
diminish at will the temperature of the steams at outlets n and (diagrammatic
plan) by throttling them and by their passage in the aspirator J to form the motor
Huid utilised under the piston.
Sheet IV. Coefficient of equilibrum. Letters corresponding to the letters of
the theoretical part Sheet 1.
E the whole apparatus. pipe bringing the fluid from the recuperator No. 1.
gg tubular cooling system. suction pipe taking back the cooled fluid to the air
pump. pipe taking condensed liquid to the feeding pump.
Letters concerning the special construction of the apparatus.
A plate perforated conically in contrary direction to the effect obtained. B inlet
for the cooling water. C discharge of the heated water. D D openings which
may be closed by solid plates allowing the apparatus to be worked either with free
delivery or shut the coefficient in this latter case acting in the manner of the
recuperator No. 1 without circulation of cooling water. When the openings are
left unclosed and there is a circulation of cooling water the apparatus serves to
produce a vacuum. S reservoir for the condensed water. R R valves allowing
the vacuum in the reservoir S to be intercepted and the condensed water to be
returned by one or other of the methods above mentioned without the pumps
having to work against the vacuum produced in the whole.
T. Tap for emptying the reservoir S.

page_text: Sheet V. Superheater motor aspirator.
Letters corresponding to the same letters of the diagram (Sheet I).
binlet for the positive superheated steam. n inlet for the superheated negative.
steam. c outlet for the mixture of fluid called ponderable caloric..
Letters relating to the special construction of the apparatus.
A. a chamber for the preliminary preparation of the positive fluid, on account
of the throttling of the steam in its passage through the conical interstices i i
made in the plate P. These conical interstices are placed in the required direction
(that is to say the larger openings to the entrance of the steam) to restrict its
passage (first throttling changes the molecular nature and again increasing the
initial temperature by the aid doubtless of an addition to the sum of latent heat
brought in in the act of vapourisation).
PP perforated plates.
ii conical interstices formed in this plate (see A above) BB first preparation
chamber for the negative fluid. PI plate perforated in the same manner as the
plate P (the same cones of small diameter left for the passage of the negative
steam, but in greater number because of the difference in section at and n).
conical perforations in the plate P. C conical nozzle (path of the positive
steam) D open space, conical part (path of the negative steam) mixture of the.
two steams (already transformed in the chambers A and B). Formation of the
final ponderable caloric fluid (see preamble, No. 3).
Note. In the perforated plates of the coefficient apparatus, Sheet IV, the cones.
are placed in the contrary direction, that is to say, allowing by reason of the
expansion given to the fluid, a useful rapid cooling effect.
Sheet III. Supplement to the description.
Superheater-furnace, p. Tubes taking the form of the said furnace, embedded
in the masonry which surrounds it, and therefore collects the heat lost by radiation.
This collection may be taken into the cycles either by means of the water or by the
passage of one or other of the two steams. v superheater ash pit. Collection of
the heat of radiation below the grate as well as the caloric taken away by the red
cinders falling from the grate. This collection may be made at will either by
water or by steam.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that I claim ny
system of utilising steam in motor engines working by the action of three combined
cycles as described and illustrated in the annexed drawings and I claim as essential
features of my invention :-
1. The formation of the motor fluid by the mixture of two steams, one called
negative steam taken from steam which has previously done work in the cylinder,
and the other called positive steam taken from the boiler, which boiler receives
part of the condensed steam which has already done work, the other part of this
condensed steam being led to the recuperator No. 1.
2. The contraction or partial condensation in the apparatus which I have called
a coefficient of equilibrium (a kind of compensating regulator for steam which has
just done work) and the utilisation of the portion remaining in the gaseous state,
which forms a portion of the steam called negative steam after three successive
heatings, first in the recuperator No. 1 by heat given out by contact with the
steam passing from the cylinder, then in the fireless boiler or recuperator No. 2
and lastly in a superheater before being mixed with the positive steam.
3. The superheating of the additional or positive steam furnished by the boiler,
this superheater allowing if desired as in the preceding case the utilisation of heat
lost in the hearth of ordinary boilers.
4. The use of a main aspirator for effecting the mixture of the two steams
coming from their respective superheaters, the one the positive entering through
the interior and drawing the other the negative steam from around the nozzle.
5. The use of a small aspirator for facilitating by aid of a small quantity

page_text: of positive steam, the delivery of steam or liquid passing from the recuperator No. 1
into the fireless boiler No. 2.
T
6. Construction of the coefficient of equilibrum with a conically perforated cooling
plate above the system of tubes opening into a lower reservoir which receives the
condensed steam, the conical perforations presenting their small orifice to the entering
'steam.
7. The arrangement of the two superheaters, joined with the fireless boiler or
recuperator No. 2 heated by the same furnace in which the lost heats are
'utilised.
8. The combination of apparatus forming the whole of the system by the connec-
tions set forth and constituting the three cycles, steam cycle, heat cycle and water
cycle working separately or in combination.
9. The employment of what. I have herein called recuperator No. 1 acting as
low pressure generator, and regaining energy from the heat of the exhaust Huid
hitherto lost.
10. The special construction of the superheater furnace giving protection to the
heater tubes from the direct action of the fire.
11. The construction of the superheater in the manner hereinbefore described to
allow of the easy changing of the heater tubes; and the elimination of one or
several by means of special connecting unions and providing direct communica-
tion m¹n between the boiler or the boilers and the aspirator to avoid all risk of
stoppage.
12. The construction of the superheater substantially as described partly of
iron and partly of copper so utilising their difference of conductibility to retake in
the same period of time about the same amount of heat in spite of diminution of
intensity in the heating medium.
13. The construction of the superheater in one piece with the recuperator No. 2
making use of the necessarily elevated temperature of the issuing gases and regaining
heat hitherto lost.
14. The construction of the aspirator apparatus with plates having a number of
conical perforations formed through them substantially as described.
Dated this 13th day of May 1805
CARPMAEL & Co.,
Agents for the Applicant.