US2825317A - Steam separator - Google Patents

Description

March 4, 1958 A. A. TACCHELLA ET AL 2,825,317

' STEAM SEPARATOR Filed Jan. 9, 1956 IN V EN TOR5 14001 PH 4. 7462715 41,4 ARNOL D N. ANDERSON Q Jam STEAM SEPARATOR Adolph A. Tacchella, Altadena, and Arnold N. Anderson, Manhattan Beach, Calif.

Application January 9, 1956, Serial N0. 558,116 7 Claims. (Cl. 123-4123) This invention relates to steam separation means in the cooling systems of internal combustion engines and is an improvement of the cooling system disclosed in pending application, Serial No. 492,521, filed March 7, 1955, of co-inventor Adolph A. Tacchella, now Patent 2,766,740, ,issuedOctober 16, 1956.

Since Water is the usual liquid used in the cooling systems ofinternal combustion engines, this disclosure will consider water only, although other liquids, such as kerosene, alcohol, etc.,' alone, or mixed with water may be used. The vapor phase of the Water in the present system will be referred to as steam.

The invention contemplates a cooling arrangement in which Watercirculates through an engine at or near its boiling pointv and the principal area of heat transfer is in a state of ebullition, the cooling of the heated surfaces of the engine-taking place by ebullition. In the cooling systems of engines with high specific output, for instance, such an arrangement has many important advantages, among which is that the heat transferrate of boiling water is much greater than the conventional heat transfer by convection only.

If boiling is not a factor, the temperature of any given portion of the cylinder head walls of an engine depends, largely, on the coolant velocity over and past such walls. It is a practical impossibility to obtain uniform water velocities through the complex maze of cored passages-of a cylinder head. Hence, some areas of thehead necessarily run hotter than others. On the other hand, metal temperatures in a cylinder head, cooled by ebullition or boiling, are substantially more uniformthroughout than if cooling is by convection only.

, Another important feature of the present invention is that the same deals with an arrangement in which the coolant is circulated by the action of the steam generated on the hot surfaces. in the water passages of an engine and which, while rising through the passages, carries a surplus of coolant to adequately wet said surfaces.

, Accordingly, an object of the present invention is to provide an efiicient liquid cooling system, for the purposes indicated, that operates with a coolant maintained at a temperature sufficiently high so as to eifect the principal transfer of heat by ebullition or boiling.

Another object of the invention is to provide an improved separating means for the water and steam mixture circulating from the cooling passages of an engine, the same being especially efiicient to induce free circulation of the coolant circuit and rendered so efiicient by the absence of restrictions to the circulation.

A further object of the invention is to provide an engine cooling system that operates in a manner to effect a low temperature differential between the temperature of coolant circulating to the engine, on the one hand, and the temperature of coolant circulating from the engine, on the other. This important feature not only results in reduced taper between the top and bottom of a cylinder usually caused by temperature differential, but the higher.

temperature in any part of the cylinder actively prevents United States Patent "F ce or inhibits condensation of products of combustion on cylinder walls under load conditions, such condensation usually causing corrosion, sludging and excessive wear.

A still further object of the invention is to provide a cooling system of the character referred to having adequate venting at all times. This feature is important because raising water to its boiling point causes elimination therefrom of air and other non-condensible entrained gases, and adequate venting provides for free escape of such air and gases and further affords ready egress from the system of any leakage from the combustion chamber of an engine into the cooling spaces therearound.

I Other objects ofthe invention are to provide a cooling system in which aeration of the coolant is prevented; to which coolant may be added while the system is in operation and under all load conditions; and which may be used to eitect heat exchange as with a cooler for the lubricating oil of an engine.

. A yet further object of the invention is to provide a cooling system that operates to provide a constant operating temperature of an engine regardless of fluctuations of load, speed or ambient temperature. I

The invention also has for its objects to provide such means, that are'positive inoperation, convenient in use, easily installed in a working position and easily disconnected therefrom, economicalof manufacture, relatively simple, and of general superiority and serviceability.

The invention also comprises novel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course of the following description. However, the drawing merely shows and the following description merely describes one embodiment of the present invention, which is given by way of illustration or example only.

The figure is a semi-diagrammatic view showing the application of a preferred form of the present liquid cooling system to a conventional automotive installation of motor, radiator and fan.

The engine 5 that is illustrated is generally conventional of a water-cooled internal combustion engine that operates on a variety of different fuels. In'the usual mann'er, said engine is provided with a line or conduit 6 from which coolant, a mixture of water and steam, is discharged and a line or conduit 7 to conduct return water to the engine. The radiator 8 is also generally conventional as is the fan 9. It'will be understood, of course, that said fan is driven by engine 5 although not so shown.

The liquid cooling and steam separating system for said engine 5 that is illustrated comprises, generally, a steam separator 10 that receives the water-steam discharge of said engine through conduit 6, returns the water of said discharge to the engine by way of conduit 7, and directs the steam of said discharge into a conduit 11; a steam jet circulator 12 that receives the flow from conduit 11 and induces an acceleratedflow into the top of radiator 8, and a similar flow, by Way of a conduit 14, back to the separator lit; a displacement and vent tank 15 connected to the top of the radiator or, as shown, to the outlet end of steam jet circulator 12 and preferably located at an elevation above the top of the radiator; and a flow circuit 16 between the steam jet circulator 12 and the bottom of the'radiator and including a circulating pump 13 and heat exchanger means 17, said circuit establishing a radiatorflow circuit that is independent of the flow circuit thr ugh the engine and the steam separator.

The steam generator 10 is shown as comprising a preferably vertically disposed housing 18 to which the conduit 6 has a tangential connection 19, said connection being preferably made to the housing about midway between its closed top and bottom. A tubular insert 20, vertically disposed within housing 18, divides the interior of the separator into an outer chamber 21 that is receptive the discharge from conduit 6, and an inner chamber 22.

Openings 23 in insert 20'comrnunicate the chambers at the bottom of the separator and a space 24 communicates said chambers at the top. Insaidspace there is showntransverse'bafiles 24a that are, therefore, interposed between the open upperend of insertZO and-the connection of conduit 11 to the .top of housing 18. Conduit 7 connects to the bottom of said housing and to the space 25 that is in common communication with chambers 21 and 22. Liquid in space 25 will-drain back to the engine through conduit 7 and steam rising in space 24 enters. conduit 11.

The steam jet circulator 12 is shown as comprising a preferably horizontal housing 26 into one end of which a steam jet nozzle 26a is introduced, the'latter being provided on the end of conduitll. Within saidhousing is disposed a venturi tube 27 into which nozzle 26a discharges and the accelerated flow from tube 27 discharges directly into the top of radiator 8.

The fiow conduit 14 has its inlet end 28 disposed in the path of discharge from venturi tube 27 and receptive of some of such dischage. The outlet end of said conduit 14 radially enters housing 18 of the steam separator 10 and extends into chamber 22. Said outlet end is provided with a float valve 20 that has a control float 32 that is buoyed upwardly by the water in the separator when at the level 33.. When suflicient steam has built up in chamber 22 to cause said level 33 to lower, the fioat 32 will drop accordingly and valve 29 will open to allow discharge of the flow in conduit 14 into the chamber 22 and, thence, into space 25. t

The venttank 15 is shown as provided with a vent 30 to atmosphere, the same being provided in the filler cap 31 through which water may be introduced to replenish any losses there may be in the radiator circulating system.

The fiow circuit 16 is shown as a water circulating line 34 from the bottom of radiator 8 to housing 26 of the steam jet circulator, said line 34 entering said housing rearward of the discharge from nozzle 26a. A temperature-actuated switch 35 may be provided in line 34 for reasons later explained. The flow is accelerated by the pump 13.

The heat exchanger 17 may conventionally be used to utilize the temperature of water in line .34 to cool any flow in lines 36. The latter lines may circulate lubricant being used by the engine or for other analogous purposes.

The steam and water mixture from the engine 5 enters outer chamber 21 of the steam separator at high velocity and by reason of the swirling motion directed thereto, causes considerable turbulence in said outer cham-' her as thesteam in said mixture rises and the water therein settles. Thus, the turbulent water in the outer chamber finds entry through openings 23 intothe quiet of inner chamber 22. Similarly, the turbulent steam in the outer chamber finds entry through space 24 into the quiet of said inner chamber 22. Since there is little or no turbulence in inner chamber 22, the water entering the bottom thereof is substantially free of steam and gas bubbles. It is this steamand bubble-free flow of water that returns to the engine by way of conduit 7.

The circulation to the steam separator 10 is similar to the circulation in a water tube steam boiler. The steam bubbles forming in the engine jacket and cylinder head rise and carry the water along. The column of'water in the inner chamber 22 is, of course, much heavier than the column of steam and water in the engine, in conduit 6, and in outer chamber 21 of the separator. This difference in weight of the two columns together with, the action of the expanding steam bubbles in the latter .column, as said bubbles rise, causes efiicient .andl'apid (L culationin the circuit that comprises the engine, .thesteam separator and the two conduits 6 and 7. I

The steam jet circulator 12 servesa three-fold purpose: as, msanslor acceleratingthe flow of the coolant in the radiator circuit, as a condenser for the steam from the steam separator 10, and as a condensate return means to the separator. The mentioned radiator circuit comprises circulator 12, radiator 8, and conduit 34 and pump 13 of the flow circuit 16.

The displacement and vent tank 15 serves to vent the system by reason of the connection with the circulator housing 26 adjacent to the radiator. Air liberated by the boiling of coolant water and other non-condensable gases, which enter. the steam separator, are carried along with the steam into the top of radiator 8 and also into tank 15. The latter is vented through vent 30. Since tank 15 is at atmospheric pressure,.the filler cap 31 may be used for adding coolant to the system during operation of the apparatus. Said tank 15 also accommodates increase in the volume of the water in the radiator circuit at elevated temperatures, and also of the water carried over into thecircuit with the steam from the engine-circulating circuit. At high loads, the steam generated in the engine-circulating circuit displaces a considerable amount of water which is carried over into the steam separator and causes a rise in the water level therein. Much of this water is, in turn, carried over with the steam into the radiator circuit from whence it is discharged into tank 15 by way of its connection to housing 26. This water transfer from the separator 10 to the tank 15 continues untilthe water level in the separator is low enough to cause the float-controlled valve 29 to establish a balanced condition between the water carried over with the steam and the amount of water returned through conduit 14 to the separator.

Should the engine load drop, less steam will be gener ated and the pressure in the separator '10 will drop, accordingly. This drop will cause a return of water from tank 15 to the radiator circuit through said tanks connection with housing 26. As the quantity of steam within the engine 5 decreases, water will be drawn through the open float valve 29. The change in water level in tank 15, returning water to the engine as required, occurs during change or" load conditions.

Operation Before starting, the system is filled with coolant water through the conventional cap on radiator 8, after which said cap is tightly closed. The usual overflow pipe, if present, is also tightly closed. The engine 5 and separator 10 receive this water by Way of conduits 14, 6, 7 and 11. The water in the engine heats rapidly, after starting, setting up circulationbetween the engine and the steam separator 10.

As the temperature of the coolant in the engine circuit reaches the boiling point, steam will be generated in an amount commensurate to the load conditions on the engine. The pressure of this steam. rises in the separator 10 and forces water in conduit 11 outwardly through nozzle 26a. The steam follows thiswater and the same carries coolant water into the venturi tube which imparts high velocity to the coolant. At the same time, the steam in the coolant water will be condensed due to the restriction imposed thereon by said nozzle and the entry portion of the venturi tube- That amount of the coolant that was initially steam is returnedto the outer chamber 21 of the separator. The conduit 14 receives this water ata slightly higher pressure than exists in separator .10. This is due to the velocity pressure at inlet 28. This pressure, however, is not sufficicnt to openthe float valve which is initially released by the lowering of the water level 33 as caused by the increase of steam .andgits pressure Within the separator. In practice, conduit 14 isso proportioned as to return water somewhat-in excess of the amount initially :represented .bys eam passingt h on uit 11. C nsequ nt y. re a dl ss. of th amount .of ste m within the engine. the water :level; 33 wi1l'be maintained at a level determined by the action of the float valve-29. 2

asaaarr The radiator circulating system 16 operates on the condition that fan 9 is operating to remove a large proportion of the heat imparted to the circulating water caused by steam condensing in circulator 12 and particularly the venturi 27 therein.

Since the flow of the radiator circuit is wholly independent of the flow of the engine circuit, it will be clear that the radiator water will normally be considerably cooler than the engine water. Accordingly, it is possible to maintain a lubricating oil temperature that is lower and, at least, not higher than the temperature of the engine water.

The limit switch 35 will close if the temperature in conduit 34 becomes higher than a pre-determined maximum. The same may control the ignition system. for instance, to stop the engine under abnormal conditions, as when the fan belt breaks, the radiator becomes excessively clogged or air flow for cooling said radiator is impaired.

Two or more steam jets may be used, if desired, instead of the single one shown.

While the foregoing has illustrated and described what is now contemplated to be the best mode of carrying out the invention, the construction is, of course, subject to modification without departing from the spirit and scope of the invention. It is, therefore, not desired to restrict the invention to the particular form of construction illustrated and described, but to cover all modifications that may fall within the scope of the appended claims.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

1. In apparatus for circulating the coolant water of an internal combustion engine, the improvement comprising a steam separator, a tube centrally located within said separator and dividing it into two concentric chambers, said tube being spaced away from each end of said separator so that said two chambers are in both upper and lower communication, a conduit connected to the outer one of said chambers to conduct a flow of coolant water and intermixed steam from the engine to said chamber, a second conduit connected to one end of the separator to conduct a flow of coolant water back to the engine, a third conduit connected to the other end of said separator, a jet device connected to said third conduit which is receptive of steam and such water that is carried thereby and which exists from the separator, said jet device inducing accelerated flow of the steam and water that I it receives and embodying means to condense said steam, and fourth conduit means to conduct part of said condensate and water back to the inner of the two concentric chambers.

2. In apparatus according to claim 1, said fourth conduit having an inlet end in the path of flow of said steam condensate and water in the jet device and having an outlet extending into said inner chamber.

3. In apparatus according to claim 1, said fourth conduit having an inlet end in the path of flow of said steam condensate and water in the jet device and having an outlet extending into said inner chamber, and a back flow-checking valve at the discharge end of said conduit.

4. In apparatus according to claim 1, said fourth conduit having an inlet end in the path of flow of said steam condensate and water in the jet device and having an outlet extending into said inner chamber, and a floatcontrolled valve on the discharge end of said conduit,

said valve being closed by the level of coolant water in the inner chamber.

'5. In a vertically disposed steam separator, the combination comprising a housing, an open-ended tube vertically disposed within said housing, said tube being centrally located and spaced away from each end of said housing, said tube dividing said housing into inner and outer chambers, with each of said chambers being in communication at their upper and lower ends because of the spacing of said tube, an inlet conduit for conducting a fiow of coolant water intermixed with steam into the mentioned outer chamber, a second conduit for conducting a fiow of steam and such water that is carried thereby from the mentioned space in the upper end of said housing, a jet device connected to said second conduit and receptive of said flow of steam and water to accelerate said flow and embodying means to condense said steam, at third conduit for conducting said condensed steam from said jet device to the mentioned inner chamber, and a fourth conduit for conducting a flow of coolant water from the space in the lower portion of said housing.

6. In a vertically disposed steam separator according to claim 5, a float-controlled valve on the discharge end of the third conduit, said valve being closed by the level of coolant water in the inner chamber.

7. In a vertically disposed steam separator according to claim 5, a plurality of baffles in the mentioned upper space.

References Cited in the file of this patent UNITED STATES PATENTS 1,485,390 Gowing Mar. 4, 1924 2,417,591 Du Rostu Mar. 18, 1947 FOREIGN PATENTS 670,161 France Aug. 17, 1929

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