US8380A - Engine in which compressed air or other gas heated and expanded by admixture therewith of - Google Patents

Description

W. MT. STORM. HYDRO-ATMOSPHERIC PO ER.

No. 8,380. Patented Sept. 23, 1851.

UNITED STATES PATENT OFFICE.

WILLIAM MT. STORM, OF TROY, NEW YORK.

ENGINE IN WHICH COMPRESSED MR OR OTHER GAS HEATED AND EXPANDEDBY'ADMIXTURE THEREWITH OF A HEATED FLUID lS USED AS THE MOTIVE AGENT.

Specification forming part of Letters Patent No. @380, dated September 23, 1851.

To alt whom it may concern:

Be itknown that 1, WILLIAM MT. STORM, of

New York, (at present resident near Troy,

which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification.

This mode of obtaining motive power is in a measure a modification of and in some respects an improvement on a method of obtaining motive power by means of air, first compressed and then heated by the combustion with it of charcoal in a close vessel, (termed the discharge-chamber,) discon nected at that time from the air-reservoir, 8rd, (thereby having its tension, &c., augmented without causing reaction upon the compressing force,) for which Letters Patent were issued to me February 4, 1851.

In the present mode, instead of conveying the combustible, as in the former case, directly to the discharge-chamber, from whence, after supporting combustion, the air, or rather the hot products of combustion, proceeded di rectly to the working-cylinder, I employ a' fluid medium, as water or itsvapor, (steam,)'

the combustible being made to yield its heat to this by combustion, and this to the air by being introduced into the discharge-chamber m lieu of the combustible. By this employment of a medium I attain several desirable advantages over my former mode. For in stance, I am not necessarily confined to charcoal as the kind of fuel employed. I avoid the inconveniences of residue incident to I that method, and the appliances for its prevention in or removal from the engine.

employed, the rationale being this: a given quantity of caloric is needed to efiect, in addition to a given initial tension, a given amount of ultimate expansion of a given quantity of air beyond its original volume previous to compression. Now, although a given amount of charcoal will yield this desired quantity of caloric on combustion, (and thereby almost any amount of initial tension,) it must first evolve that caloric at a high intensity, producing great and undesirable local heat, whereas a certain volume of steam-say at one hundred pounds pressure per square inch-coutaining this desired quantity of caloric will have a maximum intensity of heat or a temperature of only 332 Fahrenheit, (if not superheated,) yet holding a large quantity of caloric in a latent state, This, when the steam is yielding heat to the air by commixture with it, though a portion is condensed, keeps the remainder at such a temperature as it would have possessed if just evaporated under the pressure to which it may then be subject. Thus the latent heat, as it were, acting as a reservoir to the sensible, the whole is gradually, yet quickly,

yielded and rendered available for heating the air until all the steam is condensed or until the steam and air are equal in tension and temperature.

For the better elucidation of the hydroatmosphericprinciple, I refer to a sketch hereto annexed, which, however, is not intended as a representation of exactly proportioned and formed and properly operative apparatus, but is introduced as explanatory. A is the working-cylinder of an engine, the piston-rod of which (as well as passing forward to the cross-head, 8m.) passes backward throughthe rear head of the cylinder and serves likewise as the piston-rod of a double-acting compressing air-pump B, sub stantially of any usual form,which discharges into the compressed-air reservoir C, which communicates by means of a pipe provided with a shut-cit cock A with a vessel or discharge-chamber D, which communicates, by a narrow passage or pipe provided with another cock B, with the working-cylinder.

E is the heater, which may be made in most respects like a steam-boiler (except of comparatively diminutive size) and have attached similar devices for indicating height of water, pressure, temperature, &c. A siphonshaped pipe with its bow rising over the top of the heater projects one leg 0 down into the water in the heater below its usual and proper level a: as, while the other leg D terminates in the steam dome above the waterline. Each leg has a hand-cock E and i4" placed outside of the steam-dome, so that by opening one of these-while the other is closed the charge-pipe G" leading from the bow of the siphon-pipe may be filled with either steam or heated water at will. There is also a superheating-pipe H, which, branching from the charge-pipe, passes down into or through the furnace of the heater-and again returns to the charge-pipe a short distance above where it leaves it. Between the points of its departure and return there is a handcock I, which being closed obliges the steam to pass through the superheatingpipe (thereby receiving an excess of calorie and becoming what is well known as superheated steam) instead of passing from the heater directly on through the charge-pipe to. the charger F, over which there is a cook J for disconnecting it at the proper time from the charge pipe and heater.- Below the charger there is also a cock K for similarly disconnecting it from the discharge-chamber. Now, suppose the piston of the working-cylinder to commence its stroke from right to left on the sketch, during said stroke mechanism connecting with the cocks J, K, A, and B, and operated by themotion of the engine, will first open and close A, allowing the discharge-chamber to fill with compressed air from G and then shutting off their connection with each other. I is then opened and closed, permitting the charger to lill with steam (simple or superheated or with heated water, according to the positions of the'cooks I, E, and E) from the heater and then sh u tting off its connection therewith.- Kbeing now opened, the charge of steam, or whatever the medium may be, will pass into the discharge-chamber and a commixturc of the air and steam is effected.

The effects that immediately ensue on communication being made between the compressed air and the medium are somewhat complicated and diflicult to explain minutely. It simple steam be the medium, on its commixture with the air it would yield heat to the latter, which (the tension of both being supposed about equal previous to commixture) would cause it. to much exceed the former in tension and thereby compress it, the consequence of this compression of the steam being a corresponding elevation of its temperature above that which it originally possessed at the commencement of the process and under a less pressure, (that under which it was generated in the heater,) this increase of temperature reacting on the air again increasing its tension, which reacting upon the steam would again cause its further compression, &c., these successive effects being constantly reproduced. until the air and steam were about equalized in temperature and ten-.

sion. The increase of tension produced in the air through the heat yield ed by the steam is a little diminished in rapidity and extent by the expansionoi' the former into the space evacuated by the latter on each successive condensation of those portions supplying this heat to the air, (the exact portion of the Whole charge of steam thus condensed depending on the relative proportions of the quantit es of air and steam commixed and the relat1ve specific caloric of those fiuids,) and on each reduction by compression of the remainder in volume d no to the increased tension of the air effected by each additional quantum of heat so supplied to it. If water heated under a proper and sutficien't pressure constituted the charge of the medium, on entering the discharge-chamber, or its equivalent, a portion would flash into steam according as the restraining pressure was less. The remainder would fall in temperature, the vaporous portion acting upon the air, did, much as in the previous case. If superheated steam were employed as the medium, the effects would again vary in a degree dependent on the quantity of its heat in excess, and it might be made sogreat that no condensation would take place until the piston had advanced some distance on its stroke, or not even then. It may be, and doubtless is, advisable to generate the steam (when it be the. medium) at about one h undred pounds pressure per square inch, (the corresponding temperature being 332 l ahrenhcit,) and superheat it to about 600 Fahrenheita little more or less.by which means a higher initial temperature 1s obtained'without an inconvenient amount of pressure of the medium, that cited being, asa geueralrule, aboutsulticient. 'lhecommixturc of the air andsteam and resultant elfects being consummated almost or quite instantaneously, B opens, and the charge acting upon the piston propels it to the opposite end of the cylinder, (and the main pistonand that of the air-pump being connected directly or indirectly a charge of air is compressed at the same time,) where all the apparatus within the dotted circle (see sketch) being duplicated, and connected by branch pipes from the charge-pipe G and from the reservoir 0, the same operations and effects are similarly rep oduced on the opposite side of the piston, thus continuing the motion of the eugine. As the charge of air and steam enters the main cylinder, expanding behind its piston, a still furthercondensation of the former takes place, owing to the fact that the tendency of the air is to diminish in temperature at about the rate it increases in volume, whereas steam, as is well known, does not lose temperature on expansion in nearly so rapid a ratio, and caloric having a tendency to equilibrium the steam will be continually yielding heat to the air and condensing until all is condensed or the temperature of both are equal. If the medium be superheatedinstead of saturated or simple steam, this condensation will not ensuc'until the heat in excess shall be exhausted, each degree of superheat in the steam, it will be borne in mind,

'priate means to the heater.

being constituted, if the term may be used, of a quantity-of -caloric equal to that producing about 3 of temperature of the same weight of air at the ordinary density, equal to-about 6 of the same at a double density, &c., the specific heats of steam and air each being treated as a permanent or fixedly aeriform fluid, being held as about thus-water taken as unity-steam, 0.84; air, 0.26.

In reference to operating the mechanism so as to continue properly the alternating strokes of the engine, B'- or its equivalent may be closed at the same moment its du-.

plicate at the opposite end of the cylinder is opened, and vice versa. K and its duplicate may be similarly operated in regard to each other. where a cock operated by the engine alternately opens the communication to either end of the cylinder, permitting the escape at the proper time of the heated air and water, the latter being reconveyed by some appro- Although this power fromits very nature must work expansively, it may be made to work still more so, although it would be to doubtful advantage at most. This may be efiected by having puppet-valves ineach of' the connecting pipes or communications between the discharge-chamber and the charger, air-reservoir, and main cylinder, each of these valves openingtoward or into the former. Now, cocks J, K, A, and B being disconnected fromthe engine and left open, the air and steam would, by their elasticity, open the puppetvalves, interrupting their course to the discharge-chamber and rush into it, whereon greater tension would be therein produced during and by ,their commixture than existed in either air reservoir or heater, and the puppet-valves would be closed by re action, shutting off their communication with or disconnecting them (the reservoir and heater) from the discharge-chamber, the puppet-valve between the latter and the working-cylinder being closed at the same time from the same cause and. so remaining until the main piston returns toithe end of the cylinder at which this valve is located when, as the engine passes the dead-point, it

may be opened by some convenient device ing any further supply to the cylinder from the discharge-chamber during the stroke.

Other liquids than water may be used for The eduction of the engine is at L,

gree of compression, than air; but as water and air are the most universal elements in nature theyare naturally preferable for this purpose.

Apart from the cleanliness and compactness resultant from the hydro-atmospheric mode of driving engines, it is less capable of producing extensive injurious effects from explosion, and its economy may be inferred even without the aid of such data as follow.

Air and other gaseous bodies at a temperature, say, of 60 Fahrenheit, if heated to 540 Fahrenheit will be found doubled in tension if heated without being allowed to expand, or under a constant density, no matter what that tension, due to compression or prior to heating, may have been; or they will be doubled in volume if they are allowed to ex-- pand or kept under a constant pressure while heating. (When either doubled in tension or volume by heat, however, although their temperature will be found the same, the quantity of caloric absorbed will be far greatest about doublein the latter case.) The specific caloricof air as compared to that of water for equal weights of each is about as twenty-six to one hundred, or, say, as one to four. One pound of coal will generate, say, eight pounds steam, (such being a good average at the present time,) which at one hundred pounds pressure per square inch will equal about thirty-two cubic feet. Now, the equivalent weight of air (having reference to the comparative specific heats) at an equal density would equal more than sixty cubic feet, (the force outlayed in compressing this air to the above-mentioned or any other density being of'course returned, minus loss byvleakage and friction on its re expansion) and this quantity of air almost double in volume to its equivalent of steam (the thirtytwo cubic feet) is, as has been explained, so largely increased both in tension and volume by its commixture with the steam as to render it obvious that by employing the latter as a source of heat for expanding compressed air far more power may be obtained at an equal cost, not to mention the many collateral advantages, than can be by employing it as a direct mover.

Having thus fully described the nature of my invention, what I claim, and desire to secure by Letters Patent of the United States, is

Actuating an engine-such as are now usually driven by steam, or of any convenient form'by means of a measured orldetailed quantity of air previously compressed and having had its tension, due to such compressiou, highly increased and augmented by the jetting or flashing into or eommixture with it of a measured or detailed quantity of a me dium, or, in other Words. of a heated liquid,

as wafeigor a vapor, (simple or superheated) as steam, said jetting of the steam into the air (orvioe versa, the air into the steam, which I claim as equivalent) and their commixture being effected in a vessel or vessels disconnected previous to and during that process, or at least prior to its final consummation, from the reservoir or main source of compressed air and from. that of the steam, &c., and each separate and distinct charge or detailed quan

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