US1941587A - Indirect heat exchanger - Google Patents

Description

5 Sheets-Sheet 1 .ATTORNEY Jan. 2, 1934. R. H. STONE ET A| l INDIRECT HEAT EXCHANGER Filed July 2s, 195o Jan. Z, 1934. R. H. STONE Er AL INDIRECT HEAT EXCHANGER Filed July 26, 1930 3 Sheets-Sheet 2 wm M. f7

' INVENToRs ATTORNEY Jan. 2, 1934.

FIG] FIG@v Patented Jan. 2, 1934 UNITED STATES INDIRECT HEAT EXCHANGER R. Harry- Stone, Irvington, and Edwin F. Tilley, Dunellen, N. J., assignors to Titeiex Metal Hose Co., a corporation of New Jersey Application July 26. 1930. Serial No. 471,034

15 Claims.

This invention relates to heat exchange apparatus and is particularly adapted for use in connection with devices known as indirect heaters. which are used for heating apartments and the like. Such heaters comprise a casing within which a heating element is located, while air is caused to circulate through the casing and, coming in contact Withthe heater, becomes heated, and after being heated is discharged from the casing into the apartment to be heated.

The most efficient heating medium is, in such devices, a hot fluid such as steam, water etc. While the heater is stationary the heating is mainly confined to certain portions of the apartment, being unevenly distributed in the apartment.

It is the main object of the present invention to provide apparatus of the character described whereby the heat shall be more evenly distributed in the apartment.

It is a further object of the invention to provide meansfor more efficiently causing 'the heat to be radiated from the heater.

As ancillary to the last named object, it is a further object of the invention to provide for the more eflicient distribution of the air in its relation to the heater.

While a further ancillary object of the invention is to improve the construction of the heater whereby its efficiency in heating the air is enhanced.

Other and ancillary objects of the invention will appear hereinafter.

It will be apparent that the apparatus may also be used for cooling when a cold fluid is supplied to the heat exchanger. E

In the accompanying drawings which illustrate the invention- Fig. 1 is a front elevation of an indirect heater embodying the invention, with certain of the parts brokenl away and certain other parts shown in section;

Fig. 2 is a view, partly in side elevation and partly in vertical central longitudinal-section of the apparatus as shown in Fig. 1;

Fig. 3 is a fragmentary view of a detail of the apparatus;

Fig. 4 is a side elevation, partly in section of suflicient of apparatus similar to that shown in for the heater;

Figs. 1, 2 and 3, to show the application thereto.

Fig. 7 is a view, partly in side elevation and partly in section, of a still further modified formP of heater radiating tube;

Fig. 8 is a cross section of the strip employed in forming the tube of Fig. '1;

Fig. 9 is a view of a further modied form of heater radiating tube, partly in side elevation and partly in section;

Fig. 10 is across section of the strip employed.

in forming the tube of Fig. 9;

Fig. 11 is a view partly in side elevation and partly insection of a still yfurther modified structure of heater radiating tube;

Fig. l2 is a view partly in side elevation and partly in section of a further modiiied structure of tube; and- Fig. 13 is a similar view of a still further modied structure of tube.

Referring to the drawings and rst to Figs. 1, 2 and 3, the apparatus comprises a metal frame 1 which is stationarily supported in any suitable manner, as for instance, by the suspending rods 2 and 3 secured in the lugs 4 and 5 which are integral with the frame 1.

Within the frame lis mounted the heater com prising the upper header 6 and the lower header 7 held in proper relation by being secured to the side plates 8 and 9. The upper tube sheet 10,(being the bottom sheet of the upper header 6) has secured 1n it, in a fluid tight manner, the upper ends of the corrugated tubes 11, the lower ends of said corrugated tubes being secured in a uid tight manner in the lower tube sheet 12 (which is the upper sheet of the lower header 7) The corrugated tubes 11 pass through the perforations in the sheets 13 which are distributed between the headers 6 and '7 and secured to the side plates 8 and 9. These plates 13 serve to space and position the tubes 1l intermediate their ends. The corrugated tubes 11 may be of the type which is integrally formed, or may be formed of a strip, for instance as shown in the patent to Louis H. Brinkman No. 1,198,392, patented September 12, 1916.

Within the header 6 is a perforated baille plate 14.

. Communication with a source of supply of steam or other hot fluid is established with the header 6 by means of a pipe 15 rotatably mounted in the fra-me 1 by means of a ball bearing 16, while 4the upper end of the pipe 15 is secured to an elbow 17 which in turn is secured in a uid tight manner to a flexible tube 18 which is in communication with a source of supply of steam or other hot fluid. The lower header 'I communicates with a pipe 19 rotatably mounted by means of the ball bearings 20 in the frame 1, which communicates with an elbow'21 which in turn communicates with the return exible tube 22 for the steam or other system.

It Will now be seen thatthe live steam will be 7 and through the pipeA 19 into the flexible return' or drain pipe 22. It will be observed that an opening 23 is drilled and tapped in the elbow 21, such opening being adapted to be stopped. by a screw plug. Such opening provides a means, by

removing the plug, for draining the heater. It

will `also be observed that the heater, including y the headers and communicating pipes, are carried by the pipes 15 and 19 which are rotatably mounted in the frame 1 so that the heater may turn in the frame, the tubes 22 and 18 having suilicient slack and ilexibility to allow its turning movement to the extent desired.

Air is forced through the heater'between the tubes 1l by means of a fan 24 xed upon the shaft 25 of an electric motor 26 of any suitable type and connected and controlled in any suitable and well known way. AThe fan is mounted within a circular drum or tunnel '27 which is secured to the headers 6 and 7 by means of a sheet metal plate 28 which, with the tunnel, covers, on the fan side, the space encrcled by the headers 6 and 7 and the side plates 8 and 9. As the fan revolves air will be forced between the tubes 11 and out the other side of the heater into the apartment to be heated. The amount and direction of the heated air thus emerging from the heater may be controlled by shutters 29 pivoted in the side plates 8 and 9 at the air exit side of the heater.

vSecured to and extending from the side of the lower header 7 is a bracket 30 to which is bolted the motor 26.l The motor, fan and heater, it will thus be seen, comprise a unit which is rotatably mounted in the frame 1 by means of the bearings 16 and 20. To cause this unit to oscillate upon thesebearings a'pulley wheel 31 fixed upon the shaft of the motor 26 drives, by means of the belt 32, a second pulley wheel 33 which is fixed upon the shaft 34 rotatably mounted in a bracket 35 secured to the side' of the bracket 30. Also rotatably mounted in the bracket 30 but upon an axis perpendicular to that ofthe shaft 34 is a worm wheel 36, fixed upon a shaft 37 and in driving engagement with'a worm 38 iixed upon the shaft 34. Also fixed upon the shaft 37 is a crank arm 38 to which is pivoted, at its outer end, a link 89 pivoted at 40 in the stationary bracket 41 mounted upon the stationary frame 1.

It will now be seen that as the motor 26 rotates and drives the fan 24, it will also drive the shaft 34 and the worm gear 38 thereon, which in turn will drive the worm wheel 36, rotate the shaft 37 and the crank 38. yThis obviously will cause the distance between the pivot 40 and the shaft 37 to alternately lengthen and shorten, thereby causing the unit comprising the heater, the fan and the motor to oscillate in the bearings 16 and 20.

This oscillation will cause the heated airissuing from the heater to be projected to diierent parts of the room so that the apartment will' be more thoroughly and uniformly heated. The

apparatus .thus described enables vthe heat derived from steam or other hot uid, which isthe most eilicient manner of heating but which usually radiates its heat from xed radiators whereby the heating of the apartment is ineflicient and non-uniform, to be utilized 4in such manner that the apartment vis -efficiently .and uniformly heated.

vequally distributed and ineilicient.

the area of the fan. Usually the fan blades are narrower as the center of rotation is approached, which would decrease the propelling force at the same speed; also the propulsion of the air as the.center of rotation of the fan is approached, is decreased because the linear speed of the fan decreases as such center is approached. At the exact center or axis of the fan the speed will be zero so that there is no air propelling force at that point. The air propulsion, both by reason of the usual increase in size of the fan blade and also the increase in linear speed, increases as the distance from the center yof the fan increases being, as before stated, nothing at the center of 90 the fan and maximum at its outer circumference. This, in the apparatus shown in Figs. l, 2 and 3, results in an air ilow through the heater which is least at points in line with the center of the fan and increases to a maximum at points substantially in line with the circumference of the fan. The result of this is that the heat extraction by the air from the heater tubes is un- This is relieved by deecting Vair from paths of greater propulsion to paths normally of less propulsion. By this means the propelled air is more evenly distributed, paths normally conveying little or no air being utilized for conveying more air thereby relieving congestion at some points and rarication at others, so that'the propulsion of the air through the heater is rendered more eflicient, and alsoby reason of the better distribution of the air in the heater the extraction of heat by the air from the heater (and hence making it available for heating the apartment) is more eilicient. I t has been found by tests that the amount of heat extracted from a given amount of steam passed into the heater is much greater with a fan equipped as just referred to than with the ordinary fan.

Means illustrating an embodiment of apparatus for utilization of the foregoing is shown in Fig. 4 of the drawings wherein the apparatus represented is a side elevation of apparatus similar to that shown in Figs. 1 and 2 but with the addition of a tubular member42 of frustro-conical shape interposed between the fan 24 and the heater and supported upon the heater unit in any suitable'way so that it moves with that unit and maintains a ixed relation to the fan and to the heater. This tubular member 42, it will be seen, has its wider opening adjacent the fan 24 and its narrower opening adjacent the heater mounted in the frame 1'. It will be seen that the air received from the fan into the outer por- -tions of the tube 42 will be deflected from such crease in efllciency of the heater .has already 1,

been referred to. The slope of the deilecting tube 42,-as well as its length and diameter vwill bev determined according to the circumstances of each case, such as the desired amount of concen- 'tration of air at-the center, the structure of the 1,

heater, the distribution of air desired in the heater etc., it being obvious that the greater the diameter of the tube 42 at its large end the more and higher speed air will be deected towards the center, and the greater the slope, that is the 1l lll greater the diierence in area between the large and small ends, the greater will be the deflection and concentration of the air towards the center. Bearing these facts in mind the slope, length and diameter of the tube 42 will be readily varied to suit the desired results under the conditions of the case in hand.

While corrugated tubes are good radiators of heat and thus form good radiating elements for the heat of the iluid passing through them, it is a fact that the' heated air lying between the corrugations on the exterior of the tube is pocketed in the groove between the corrugations and does not flow freely away so that the radiation or dissipation of the heat from the tube is impaired. This condition may be greatly improved and the corrugated tube as a radiator of heat may be improved by placing a'metallic or other heat conducting fin within the space between the corrugations. This conducts the heat away from itsconfined space and largely increases the heat radiating capacity of the tube byrelieving the congestion of heat which occurs in the space between the corrugations.

A device embodying this conception is shown in Fig. 6 of the drawings wherein the corrugated tube 43vis formed by helically disposing a strip having a longitudinal groove and interfolding the edges of adjacent convolutions as described inthe Brinkman patent hereinbefore referred to. This tube has the corrugations 44. Between the corrugations is ahelically wound strip of metal having a cross section comprising the radially extending fin 45 and foot 46 at right angles thereto. The strip last referred to is wound helically within the groove of the tube 43 between the corrugations 44, and the foot 46 rests upon the tube 43 between the corrugations. The strip comprising the n 45 and foot 46 may be secured to the tube 43 by soldering, welding or in other suitable ways, or it may be unsecured to the tube 43, merely resting against it.

It will be Aseen that the n 45 or' the strip canducts the heat of the pocketed air between the corrugations outwardly and dissipates it; also, the strip, including the fin 45 and the foot 46, being in contact with the tube 43 will act to directly conduct the heat from the tube outwardly, which further fact improves the radiation because heated air being pocketed between the corrugations the tube between the corrugations does not so readily radiate its heat.

In Fig. 11 is shown a modied construction of tube having a radiating n between its corrugations, the corrugated tube 47 being shown, like that in Fig. 6, as being the same as shown in the Brinkman' patent hereinbefore referred to. The fin 48, however, instead of being formed of a helical strip of angular cross section, is formedl of a at strip helically wound in the groove between the corrugations of the tube 47. The fin or strip 48 vfacilitates the dissipation of heat from between the corrugations as already explained in connection with the device of Fig. 6

- and may be soldered, welded or otherwise secured to the tube or may simply lie upon it as it is wound thereon.

The heat dissipation or radiation of a corrugated tube may also be improved by means of a iin mounted upon the outer side of the corrugation, and efiiciencyof the tube asa heat radiator may be very greatly increased by combining the corrugation with a iin upon the outside thereof over what could be accomplished with either the corrugation or the n alone. A corthere is more emcient radiation if the corrugations are made of moderate depth and a iin of heat conducting material is supplied on the outside of the corrugation. corrugation in combination with the fln= on its outside is more eiiicient than depending upon the height of the corrugation to give the desired heat radiation, for the reason that if the corrugation is made too high the heated uid in passing through the tube is apt to not penetrate into the extreme recesses of the corrugation, so that radiation'from the outer surface of the corrugation is impaired, whereas if the corrugation is made low the heated fluid within it penetrates fully throughout the corrugation and delivers its heat thereto, the fln at the outside of the corrugation acting to conduct away such heat and dissipate it into the surrounding atmosphere. Also '1t is advisablev to limit the height of the corrugation and combine it with a iin as described because a corrugation of too great depth, under some circumstances, too greatly retards the ow of heated uid through the tube.

An example of a construction of tube having a fin at the outside of the corrugation is shown in Figs. 7 and 8. In this construction a metal strip 49, of cross section as shown in Fig. 8, is wound into a helical shape when the fin portions 50 on the one hand and 51 on the other will lie along adjacent edges of adjacent convolutions, and these fin portions are then secured together by soldering, welding or in any suitable way to form the tube 52 having the corrugations 53 at the outeriend of which are the ns 54.

In Fig. 5 is shown a modied construction of corrugated tube having a n at the outside of the corrugations, this structure including a tube 55 formed from a'helically disposed strip of metal having the edges of adjacent convolutions interfolded as in the Brinkman patent hereinvbefore referred to, and having the corrugations 56, the n being provided by a helically disposed metal strip having a right angled section comprising the radial portion 57 and the foot portion 58 which is inserted in the seam of the tube as shown in Fig. -5. The fin strip may be secured .to the tube by soldering, brazing, welding or in any suitable Way or may be simply inserted withinthe joint without other securing means.

Another structure of tube having an external n on the outside of the corrugation of a corrugated tube is shown in Fig. 9. This tube is formed from a metal strip having a cross section as shown in Fig. l0, which cross section includes the radial projection 59 on one side of the strip and a similar projection, but with a hook 60 at its outer end, at the other edge of the strip. This strip is helically disposed and the radial edge 59 of one side of the strip is inserted within the hook 60 on the side of an adjacent convolution. The edges of the strips may then be secured together in any suitable manner as by soldering, welding, brazing or other suitable method. A tube V61 is then formed as shown in Fig. 9, having corrugations -62 and fins 63 at the 'outsides of the corrugations.

Also the use of thelid-5 ways. So long as the tube is corrugated the fin may be combined with it to advantage.

In Fig. 12 is shown, partly in side elevation and partly in section, an integrally formed corrugated `tube having a fin located between the corrugations, the said fin being formed of a helical strip of heat conducting material.' 'Ihis strip may be soldered, brazed, welded or otherwise suitably secured-to the tube, or it may simply lie in contact therewith. a

In Fig. 13 is shown in side elevation and partially in section, an integrally formed corrugated tube having a helical strip of heat conducting material secured to the outer side o! the corrugation by soldering, brazing, welding or in any other suitable way, this strip forming a heat radiating iin in conjunction with the corrugation.

While the invention has been illustrated what are considered its best applications, it may have other embodiments without departing from' its spirit Yand is not therefore limited the strucfluid conveying connections connected with said changing fluid to said conduits and means actuated by said electric motor for turning said unit.

comprising a heat exchanger having' uid conduits, a motor for turning said unitA and a fan for blowingair to said exchanger, said unit being turnably mounted in said support, and uid conveying connections connected with said exchanger and adapted to supply heat exchanging uid vto said conduits.

4. The combination with a support, of a unit comprising a heat exchanger havingiuid conduits, an electric motor for turning said unit and a fan for blowing' air to said exchanger, said unit being' turnably mounted in said support,A and uid conveying connections connected with said exchanger and adapted to supply heat exchanging fluid to said conduits. V

5. 'I'he combination with a support, of a fluid heat exchanger comprising headers and corrugated tubes therebetween, said exchanger being turnably mounted in sai'd support, iiuid conveying connections connected withvone of *said`v headers and adapted to supply heat exchanging fluid-to said headers and tubes and means for turning said exchanger. A

6. The combinationwith a support, of ya 'fluid heat exchanger comprising headers and corrugated tubesA therebetween, said exchanger being turnably mounted in said support, iiuid convey ing connections connected with one of said headers and adapted to supply heat exchanging uid to' said exchanger, means for turning said .exchanger and a fan adapted to blow air between said corrugated tubes.

'1. The combination with a heat exchanging element, of'means for propelling a fluid toward said element and means for defiecting iluid acted on by said means, towards the axis of said means, the outer side of said deilecting means being spaced inwardly from the circumference of said propelling means.

8. The combination with a heat exchanger, of a Ian to blow air towards said exchanger and means for deilecting said air inwardly toward the fan axis, said deflecting means having its outer edge spaced inwardly from the circumference of said fan.

9. The combination with a fan, ofa tubula member for de ecting air propelled by said fan inwardly toward the fan axis, said deflecting member having its outer edge spaced inwardly from the circumference of said fan.

10. The combination with a heat exchanger. of a fan blowing air to said exchanger. and a tubular member Vinterposed between said exchanger and fan, said member having' openings of diierent sizes at its ends, the opening of smaller size being at theexchanger end and the opening of larger size being at the fan end of 100 said tubular member, said tubular member having-its outer edge spaced inwardly from the circumference of lsaid fan.

11. The combination with a heat exchanger of means for propelling air at an interior portion of the propelled air current towards the exchanger on lines converging towards the axis of said means, there being part of the current of propelled air outside the said converging lines.

12. The combination with a support, of a fluid 110 heat exchanger comprising fluid conduits, said heat exchanger being turnablymounted in said support, uid conveying connections connected 'with said heat exchanger and adapted to supply A heat exchanging iluid to said conduits and' means 115 3. The combination with asupport, of a unit' for propelling air to said heat exchanger, said propelling means and heat exchanger being adapted to occupy predetermined relative positions -as saidheat exchanger is turned.

13. The combination with a support, of a fluid heat exchanger comprising uid conduits, said heat exchanger being `turnably mounted in said support, fluid conveying connections connected with said heat exchanger and adapted to supply heat exchanging uid to said conduits and for propelling air vto said heat exchanger, said propelling means and -heat exchanger'being xed with relation to each other. I

14. The combination with a support, of a unit comprising a uid heat exchanger and an pair propeller, said heat exchanger comprising uid conduits and said unit being turnably mounted in said support,'and iluid conveying connections connected with said heat exchanger 'and adapted tosupply heat exchangingiiuid to said conduits and a motor adapted to turn said unit.

15. The combination with a support, of a unit comprising a uid heat exchanger, an air propeller and a motor driving said propeller, said heatexchanger comprising iluid conduits and said unit being turnably mounted in said support, fluid conveying connections connected with saidheat exchanger and adapted to supply heatv exchanging fluid to said conduits and means for turning said unit by said motor.

RpHARRY STONE.

Images