US2386918A

US2386918A - Method and apparatus for projecting liquid jets

Info

Publication number: US2386918A
Application number: US417220A
Authority: US
Inventors: Timpson Lewis G Morris
Original assignee: PYRENE DEV CORP
Current assignee: PYRENE DEV CORP; PYRENE DEVELOPMENT Corp
Priority date: 1941-10-31
Filing date: 1941-10-31
Publication date: 1945-10-16
Anticipated expiration: 1962-10-16
Also published as: FR949434A

Description

Oct. 1 6, 1945. L G. M. TIMPSON METHOD AND APPARATUS FOR PROJECTING LIQUID JETS Filed Oct. 51, 194i 3 Sheets-Sheet 1 g i wy: W x

INVENTOR LEW/5 6i Mom/5 TIMPSUN TTORNEY L. G. M. TIMPSON METHOD AND APPARATUS FOR PROJEC'I'ING LIQUID JETS Filed Oct. 51, 1 941. :5 Sheets-Sheet 2 INVENTOR LfW/S 6. Mam/s 77MP50N ATTORNEY Oct. 16, 1945. L. e. M. TIMPSON 2,336,918

METHOD AND APPARATUS FOR PROJECTING LIQUID JETS Filed Oct. 31, 1941 5 Sheets-Sheet 3 44 43 .umma aaea J5 J3 m a ur INVENTOR [5 W15 6. Mom/s TmPso/v Z TTORNEY v Patented Oct. 16, 1945 METHOD AND APPARATUS roa raomc'rmc LIQUID .m'rs

Lewis G. Morris Timpson, Plalnfleld,,N. 1., assignor to Pyrene Development Corporation, a

corporation of Delaware Application October 31, 1941, Serial No. 417,220

13 Claims. This invention relates to apparatus and method for projecting a jet of dispersed liquid, and to apparatus and method for aspirating air or other gas by means of such a jet to produce fire extinguishing foam.

Fire extinguishing air foam is made by utilizing a jet of liquid to aspirate air into a receiver or other conduit. The liquid may contain, or have introduced into it substantially simultaneously with the air, a foam stabilizing material.

{The foam thus produced may be projected directly on a fire and used for extinguishing fires in the same manner that chemical types of fire extinguishing foam are used; The principles involved in making air foam are described in United States Wagener Patent No. 1,821,914.

Various problems are present in this art, one of which is the production of a sufficient number of volumes of foam from a given volume of liquid. It is naturally desirable to aspirate relatively large quantities of air with a givenvolume of liquid in order to produce as much foam as possible. It is also necessary, however, to produce a good qualityof foam and to obtain such high expansion factors in the formation of the foam without too great a loss in theforward motion of the foam, so that it can be projected directly on the fire without requiring the use of extra equipment such as booster pumps.

Another problem. which has been encountered in this field is in connection with the clogging of nozzles used for aspiration. The water from ordinary supplies that are available for fire extinguishing purposes is very apt to carry suspended particles of foreign matter of considerable size. The large particles, of course, can be readily screened out with a fairly coarse screen placed at some point ahead of the aspirating nozzle. The smaller particles, however, can only be screened out by using a very fine screen, which is costly and not always practical to use. Even when a fine screen or strainer is used in the liquid supply line, however, it is found that the aspirating nozzles have to be very accurately made and frequently inspected to make sure that they do not become clogged.

An object of this invention is to provide a nozzle that may be used as an aspirating nozzle in the making of air foam to overcome these dis advantages.

Another object is to provide a nozzle that may be used for aspirating air, or that may be used with plain water or other liquid to project a spray jet in the nature of a solid cone.

A further object of the invention is to provide air foam apparatus and method utilizing an extremely turbulent or distorted vena contracta as a means of aspirating air in the'making of air foam.

A further object of this invention is the provision of nozzles of the foregoing types that are simple and inexpensive to make, and that are, at the same time, very eflicient with'respect to the production of multiple volumes of foam from a given volume of liqui Other objects will be apparent and will be explained in connection with the embodiments of the invention illustrated in the accompanying drawings, in which- Fig. 1 is a longitudinal sectional view through approximately the center'of a nozzle suitable for purposes of this invention.

Fig. 2 is a longitudinal sectional view through a modified form of such a nozzle.

Fig. 3 isa vertical section, taken on the line 3-3 of Fig. 2. v

Fig. 4 is a view similar to Fig. 3, but illustrating a modification of the baflle plate and orifice of the nozzle shown in Fig. 3.

Fig. 5 is a longitudinal sectional view showing a further modification of a nozzle which is adjustable.

Fig. 6 is a top plan view of ducing apparatus.

Fig. '7 is a fragmentary longitudinal sectional view, on an enlarged scale, showing the aspirating nozzle and adjacent construction of the apan air foam proparatus illustrated in Fig. 6.

Fig. 8 is a vertical sectional view, taken on the line 8-8 of Fig. 6.

Fig. 9 is a vertical sectional view, taken on the same line but looking in rows 9-9 in Fig. 6.

Figs. 10 and 11 illustrate modified forms of nozzle orifices that may be used in conjunction with any of the foregoing nozzles.

Referring to Fig. 1 of the drawings, numera i5 indicates a hose. pipe or other conduit for supplying liquid under pressure to the enlarged chamber It. The sideof chamber l6 opposite pipe i5 is closed by a plate I! having a flange I8 carrying threads to engage corresponding threads on the walls of the chamber I6. This plate may, of course, be simply welded or otherwise secured in. place if desired. Plate I1 is provided with a centrally located orifice l9 having relatively sharp edges 20 inside the chamber IS. A short tube 2| is attached to the outlet side of the orifice l9 and is provided a short distance the direction of the artube 2|, it will again be substantially the same diameter as the diameter of the orifice I9.

-If the perforations 22 in the tube are not employed, the liquid jet passing through the orifice l9 will tendto form a vacuum between the outer surface of the jet and the inner surface of the tube 2|, thus causing the liquid to conform more closely to the walls of the tube 2! and producing only normal turbulence. By introducing the perforations 22 at a distance from the orifice equal to approximately the diameter of the orifice l9, however, the vacuum is broken, some air is drawn into the tube 21 and the liquid passing out through the tube 2] is highly turbulent and, in fact, is practically reduced to a solid cone of spray. The tube 2| however, should not be much longer than about three times the diameter of the orifice l9 in order to produce this effect.

The enlargement of the chamber 26 aids in producing this effect by causing the liquid flowing through the pipe IE to reduce its forward speed and move out laterally into the enlarged chamber "5. This liquid then has to flow laterally inward towards the orifice 19 in order to pass out through it. As a practical matter, it is desirable to have a chamber l6 which is in diameter at least eight times the diameter of the orifice 19. A chamber which is ten times the diameter of orifice 19 in size is satisfactory for most purposes. The orifice I9 is illustrated as circular in cross section, but may, of course, be made square, triangular, or of any other suitable shape.

Referring now more particularly to the modification shown in Figs. 2 and 3, the liquid passes through the same type of pipe, hose or other conduit I541 into an enlarged chamber 23, to which is attached a plate 24 having a single orifice .25 that is centrally located in a manner similar to the orifice l9. Flanges 26 on the plate 24 may be threaded for attachment to the walls of the chamber 23. These flanges 26 preferably also are formed with shoulders 21 to clamp the bailie plate 2Bagainst the ends of the walls of the chamber 23. Bailie plate 28 is provided with a Instead of the perforated baflle plate 29, a

simple square or rectangular baflle plate 39 may be used, which provides spaces 3| around which liquid may flow, so that it is forced to approach the orifice 32 in a lateral direction as shown in Fig. 4. Also, the orifice 32, instead of being circular, may be square or of some other multisided shape.

An adjustable nozzle is illustrated in Fig. 5

and comprises the conduit 33 with the flared portion 34 and the enlarged annular section 35 provided with threads on its outer surface. 'An integral end wall 36 may extend across the end of the enlarged section 35 and is provided with openings 31 around its outer portion. A cupshaped sleeve 38, provided with internal threads may be screwed over the enlarged section 35,'so that it can be adjusted to bring the front wall 39 a greater or less distance from the wall,38. In

the center of wall 39 an outlet orifice 40 is provided with inwardly extending sharp edges 4|. A suitable seat 42 may be formed in the wall 39 so that when the sleeve 38 is turned down to the fully closed position, the seat 42 engages the sharp edges 4| to shut oil the flow of liquid,

In normal operation, the liquid is forced to flow out through openings '31 and thence laterally in towards the orifice 40. The abruptness of this lateral flow may, of course, be varied by adjusting the sleeve 38 so that the orifice 40 is close to or a substantial distance away from the wall 36. The operation of this device is similar to that described in conjunction with Figs. 2 to 4, except for its adjustable feature which makes it possible to vary considerably the nature of the jet of liquid. 4

Referring now particularly to the device shown 49 in Figs. 6 to 9, inclusive, numeral 43 indicates number of openings 29 spaced around the outer 7 edge of the plate 28, so that liquid brought into the chamber 23 is forced to pass through the openings 29 and thence laterally inward toward the sharp inside edges of the orifice 25.

Here again, the jet of liquid emerging from the orifice 25 has a smallest diameter substantially smaller than the diameter of the orifice 25, and the extra turbulence that is introduced by means of the forced lateral passage of the liquid by the haflle plate 28 creates a high degree of turbulence in the final jet emerging from the V orifice 25.

The provision of a baffle, such as the plate 28, or other suitable means for forcing the liquid to flow toward the orifice in a lateral direction,

makes it possible to reduce the size of the chamber 23 in relation to the size of the orifice. Such a construction, therefore, is much more compact generally a nozzle for projecting an aspirating jet of liquid into a long tubular receiver 44. The

receiver 44 has a flared inlet spaced from the nozzle 43 by the spokes 45 to provide openings through which air from the atmosphere may flow into the receiver. The receiver is gradually tapered from this inlet to a hose or pipe 46 of suitable diameter which is used for delivering the foam to the fire. If desired, the tubular receiver may be provided with handles such as shown at 41 and 48.

The nozzle 43 is provided with an outwardly flared conduit 49 receiving water or other suitable liquid from the hose 59 through the valve mechanism 5|. The handle 52 of this valve may be used to control the flow of water through the device. The flared conduit 49 is provided with fianges 53 (see Fig. '7) through which bolts are passed to connect it to the nozzle casting 54 and the intermediate spider 55. Casting 54 is formed with a hollow receiving chamber 56 and a baflle plate 51 provided with suitable openings 58 around its outer edges. A nozzle or orifice plate 59 may be screwed into one end of the casting 54 and provided with a suitable central opening 60 through which the jet of liquid is projected This structure is similar in principle to that described in connection with Figs. 2 to 5.

The spider 55 has openings 6| through which the water or other liquid may flow from the conduit 49 into the chamber 56. At one side, the spider 55 is also provided with an inlet passageway 62 leading to the hollow hub 63 of the spider. -This passageway 62 may communicate 65 connected to a tank or suitable source of foam stabilizing material (not shown). The valve handle 65 may be used to control the flow of foam stabilizing material into the spider 55.

The nozzle member 61 is threaded into the central opening in the hub 63, and is provided with a tapered tube 68 extending through chamher 236 into the orifice opening 80 in the plate 59. This member 87 also has a suitable opening 62a in its side so that the foam stabilizing material may pass from the passageway 82. directly into the member 81 and thence through the tubular portion 68. Threaded into the member 61 is another nozzle member 69 having a suitable tubular nozzle 70 projecting past the opening 62a but stopping short of the entrance to the tube 68. p

The operation of this device is as follows.- Water or other suitable liquid, from a hydrant or other source of liquid under pressure, flows through the hose 50, the valve section BI and the conduit 59, through the-openings bl in the spider 55 into the chamber 56. This liquid is forced to pass through the laterally ofiset openings 58 in baffle plate Bl, so that it moves inwardly towards the orifice 80 before being projected around the end of tube 68 in the form of a highly turbulent Jet. Some of the water or other liquid coming into the conduit 49 passes through themember Ill and creates a suction at the end of the nozzle 10 so thata jet of liquid is projected into the tubular member 68 acting as a receiver. This suction device aspirates foam stabilizing material in through the passageway 62 when the control handle 68 is in the open position. The foam stabilizing material mixed with water passes through the tubular member 68 and is projected as a jet along with the water passing out through the Orifice 60 around the outside of the tube 68. As'these liq-= uids meet. they are highly turbulent and projected as a substantally solid cone of spray which draws air in through the openings around the spokes 45 supporting the receiver 44. The air that is aspirated into the liquid is churned up inside the receiver with the liquid so that foam is produced and caused to fiow along and out of the end 01' the pipe 46.-

If desired. of course, the flow 01' foam stabilizing material may be shut off by turning the bandie 68 and the device then acts as a fog nozzle projecting simply a jet of .highly turbulent and finely divided spray, which is very effective for extinguishing certain types of fire.

Various other types of orifices may be used either in the forms of nozzles shown in Figs. 2 to 5, or in conjunction with the foam making apparatus illustrated in Figs. 6 to 9.

For example, in Figs. 6 to 9, the internal portion of the nozzle including the

tubular members

61 and 69, provided for aspirating foam stabilizing material, may be omitted entirely if the foam stabilizing material is previously added to the water. Also, the nozzles illustrated in Figs. lto may beused in combination with .the receiver 44 in place of the entire nozzle 43, suitable provision being made, of course, for introducing the foam stabilizing material into the liquid stream, either when the air is aspirated or at someearlier s age.

Instead of using the nozzle orifices described above, nozzle plates such as shown in Figs. 10 and 11 may be substituted for the nozzle plates I1, 24, as or 59 with good effect. For example, the nozzle plate H is provided with four squareori- Bit fices 12 arranged in a uniform pattern and generally centrally located. Four orifices of this construction produce a highly efiective fog nozzle which is eilicient as a simple jet for extinguishing fires, and is also efilcient in aspirating large volumes of air into a receiver for making air foam. The jets of liquid emerging from these four orifices l2 join together a short distance from the orifices to form one solid jet of finely divided liquid.

The plate 73 in Fig. 11, provided with triangular shaped orifices 14 arranged in a geometrical pattern may also be used in place of the other nozzle plates described. In this instance, the jets of liquid emerging from the orifices l4 likewise merge to form a solid single jet of finely divided liquid, which is very efllcient for aspirating purposes.

The liquid jets produced according to my invention may be'described as highly dispersed solid spray jets, produced by distorted or exaggerated vena contracta which are capable of aspirating large quantities of air to produce thereby large volumes of good quality fire extinguishing foam. In this respect, the use of multiple orifices as illustrated in Figs. 10 and 11 has definite advantages for purposes of aspirating larger volumes of air.

Jets of this character also have the important advantage of unusually low capacity co-eiiicients, which means that the nozzle orifices may be made relatively large in size, compared to the amount of liquid they pass, and thus allow larger particles of foreign matter to pass through without obstruction. This advantage of my invention avoids the necessity for using fine screens, and also makes frequent inspection and cleaning of the nozzles unnecessary.

The terms and expressions which I haveemployed are used as terms of descriptionand not of limitation, and I have no intention, in the use of such terms and expressions, 'of excluding any equivalents of the features shown and described or portions thereof, but recognize that various modifications are possible within the scope of the invention claimed.

The term "solid as used in the appended claims with reference to the jet produced by the improved nozzle structure, is intended to distinguish merely from a hollow jet. Accordingly, in specifying a solid jet of highly dispersed spray, it is intended to indicate that the dispersed particles forming the spray are distributedthroughout the cross-sectional area defined by the outer perimeter of the jet.

-I claim: f

1.- Apparatus for producing fire extinguishing foam which comprises a nozzle for projecting a jet of liquid comprising a chamber for receiving a stream of liquid under pressure, said chamber having a relatively large diameter, a substantially centrally located orifice in a wall of said chamber having a sharp peripheral edge on its entrance side and forming a non converging outlet passage for the liquid, said chamber providing a passage for liquid. that has a diameter adjacent the orifice at least several times larger than the diameter of the orifice, and means within said nozzle in advance of said orifice for diverting the flow of liquid from a path directly toward said orifice without restricting the effective area of the orifice, saiii means causing the liquid to approach said orifice laterally from all sides in a plurality of impinging streams so that a solid jet of highly dispersed spray is projected from the nozzle, and a receiver open tothe atmosphere for receiving said jet and discharging the resulting stream of liquid with incorporated air.

2. Apparatus for producing fire extinguishing foam which comprises a nozzle for projecting a jet of liquid comprising a chamber for receiving a stream of liquid under pressure, said chamber having a relatively large diameter, and at least one substantially centrally located, multi-sided,

orifice, and means within said chamber constructed and arranged to cause the liquid to approach the orifice in a lateral direction in a plurality of impinging streams and to produce a high degree of turbulence in the liquid passing as a jet through the orifice, and a receiver open to the atmosphere for receiving said jet and discharging the resulting stream of liquid with incorporated air.

3. Apparatus for producing fire extinguishing foam which comprises a nozzle for projecting a Jet of liquid, a receiver open to the atmosphere for receiving said jet and discharging the resulting stream of liquid with incorporated air, said nozzle comprising a chamber for receiving a stream of liquid under pressure, said chamber having a diameter substantially larger than that of the stream of liquid supplied thereto, an orifice in a wall of said chamber having sharp edges on its entrance side and forming a non-converging outlet passage for the liquid, and baffle means in said chamber for forcing substantially all of the liquid away from a direct path toward said orifice and to approach said orifice laterally in a plurality of impinging streams directed from all sides at a steep angle to the direction of the axis of the orifice.

4. Apparatus for producing fire extinguishing foam which comprises a nozzle-for projecting a jet of liquid, a receiver open to the atmosphere for receiving said jet and discharging the resulting stream of liquid with incorporated air, said nozzle comprising a chamber for receiving a stream of liquid under pressure, said chamber having a relatively large diameter, and a plurality of nonconverging, multi-sided orifices in a wall of said chamber arranged in a geometrical pattern and each having sharp edges on their inlet sides.

5. Apparatus for producing fire extinguishing foam comprising a nozzle having an enlarged chamber for receiving liquid under pressure, at least one multi-sided, non-converging orifice having sharp entrance edges in a wall of said chamber arranged to project therefrom a solid jet of. spray, and a receiver exposed to air under atmospheric pressure for receiving said jet of sprayfrom said orifice.

6. Apparatus for producing fire extinguishing foam comprising a receiver, and a nozzle for projecting into said receiver an aspirating jet of liquid, said nozzle comprising a chamber substantially larger than the stream of liquid supplied thereto, an orifice in a wall of said chamber having a relatively sharp peripheral edge and forming a non-converging outlet passage for the liquid, and means for diverting the fiow of liquid through said chamber so that the liquid is forced to approach said orifice fromall sides in a plurality of impinging streams each from a lateral direction at a steep angle to the direction of the axis of the orifice.

I. Apparatus for producing fire extinguishing foam comprising a receiver, and a nozzle for projecting an aspirating jet of liquid into said receiver, said nozzle comprising a chamber, an orifice in a wall of said chamber having a relatively other without restricting the passage of liquid through said orifice.

8. Apparatus for producing fire extinguishing foam comprising a receiver, and a nozzle for projecting an aspirating jet of liquid into said receiver, said nozzle comprising a chamber, a plurality of multi-sided orifices disposed in a geometrical pattern in a wall of said chamber, and means for forcing liquid in said chamber to approach said orifices in a lateral direction.

9. Apparatus for producing fire extinguishing foam comprising a receiver, and a nozzle for projecting an aspirating jet of liquid into said receiver, said nozzle comprising a chamber having its cross-section gradually increasing to one substantially larger than the stream of liquid supplied thereto, an orificein a wall of said chamber having a relatively sharp peripheral edge at its entrance and forming a non-converging outlet passage for the liquid, means for projecting through said orifice a foam stabilizing liquid, and baflle means for diverting liquid flowing through said chamber from a path directly toward said orifice and forcing liquid in said chamber to approach said orifice in a lateral direction so that the diameter of the jet passing through said orifice is substantially smaller than the diameter of the orifice. r

10. A method of producing fire extinguishing foam comprising causing a stream of liquid containing a foam stabilizer to retard its forward motion and gradually expand laterally, directing said retarded liquid laterally inwardly from all sides in a plurality of impinging currents flowing toward an orifice having sharp entrance edges. and projecting outwardly through said orifice a jet of said liquid having a diameter substantially smaller than said orifice into a receiver under conditions to induce the aspiration of air.

11. A method of making fire extinguishing foam comprising directing the fiow of a confined stream of liquid laterally inward from a plurality of different directions toward a plurality of closely spaced orifices, and projecting simultaneously jets of said liquid through said orifices to aspirate air into a receiver.

12. A method of making fire extinguishing foam comprising directing the flow of a confined stream of liquid laterally inward from a plurality of difi'erent directionson all sides of the axis thereof toward an orifice having a sharp entrance edge around its periphery, and projecting a spray jet of said liquid together with a foam stabilizing material through said orifice to aspirate air into a receiver, said jet as it passes through said orifice having a diameter smaller than the orifice.

13. Apparatus for producing fire extinguishing foam which comprises a spray nozzle having a gradually enlarged chamber for receiving a stream of liquid under pressure from a conduit and transmitting the same at a reduced forward velocity, a wall on the outlet side of said chamber having at least the central portion of its inner surface nora direction transverse to the dir ction of the axisof the orifice, and a receiver for receiving the resulting jet of spray issuing from said orifice and aspirating air for incorporation with the liquid 8 of said spray.

LEWIS G. MORRIS 'I'IMPSON.