US3132190A

US3132190A - Heat exchange apparatus

Info

Publication number: US3132190A
Application number: US144727A
Authority: US
Inventors: Jr John Engalitcheff
Original assignee: Baltimore Aircoil Co Inc
Current assignee: Baltimore Aircoil Co Inc
Priority date: 1961-10-12
Filing date: 1961-10-12
Publication date: 1964-05-05
Anticipated expiration: 1981-05-05

Description

y 1964 .1. ENGALITCHEFF, JR 3,132,190

HEAT EXCHANGE APPARATUS 6 Sheets-Sheet 1 Original Filed Dec. 9, 1955 INVENTOR John Ezgqmifickafifide:

BY p Mrnv ATTORNEYS y 5, 1964 J. ENGALITCHEFF, JR 3,132,190

HEAT EXCHANGE APPARATUS 6 Sheets-Sheet 2 Original Filed Dec. 9, 1955 3&1

INVENTOR BYK 19m ATTORNEYS J. ENGALITCHEFF, JR 3,132,190

May 5, 1964 HEAT EXCHANGE APPARATUS 6 Sheets-Sheet 5 I N VEN TOR J0knE'rgaZa'Z'c7zefi, bc

Original Filed Dec. 9, 1955 ATTORNEYS y 5, 1964 J. ENGALITCHEFF, JR 3,132,190

HEAT EXCHANGE APPARATUS Original Filed Dec. 9, 1955 6 Sheets-Sheet 4 ii I M I Lll" vHI E mm m 5 L 000000000 0 0 O O (2% 3'5 INVENTOIQM Joizzz/ Ezgaihlzeff fi.

ATTORNEYS May 5, 1964 J 1221/ Eiya hlzeffJr 5%, A2 MM,

ATTORNEYS May 5, 1964 J. ENGALITCHEFF, JR 3,132,190

HEAT EXCHANGE APPARATUS Original Filed Dec. 9, 1955 6 Sheets-Sheet 6 INVENTOR 5M 19m, M/OAW ATTORNEYS pan below the contact surfaces.

United States Patent i HEAT EXCHANGE APPARATUS John Engalitchefl, Jr., Gibson Island, Md., assignor to Baltimore Aircoil Co., Inc, Baltimore, Md., a corporation of Maryland i i Continuation of application Ser. No. 552,080, Dec. 9,

1955. This application Oct. 12, 1961, $81. No. 144,727 4 Claims. (Cl. 261-30) downwardly therethrough and a current of gas such as air is also passed over the surfaces in contact with the liquid. The result of such contact is an induced rapid evaporation of the liquid which reduces the temperature of the liquid. The cooled liquid drops into a collecting Heat exchange towers as thus broadly described are conventional, and this invention resides in certain improvements in such devices which enable more economical operation and improved results to be obtained.

Heretoiore, heat exchange towers have been constructed with a fixed capacity because of the complex problems involved in'the operation of a. variable capacityfunit. Thus, such towers have generally been custom made in accordance with the particular capacity desired. The

capacity can, of course, be varied within limits by changing the velocity of the air flowing through the contact surfaces. However,-this method is ineflicient since the resistance to air flow increases much faster than the rate .of heat exchange with a given increase in air velocity. The horsepower required to move the air varies directly with thejresistance to flow. Thus, for any given cross sectional areaof the contact section of the tower, there is a maximum economical air velocity.

A more effective way to vary the capacity is to change the height of the contact surfaces. In this invention, the capacity may be varied by providing a removable contact section which may be replaced by a single contactwsection of a diiferent height or by multiple contact sections. However, the use of multiple sections also creates a problem of high resistance to air lflOW, which problem is minimized by this invention.

As will be more fully explained hereinafter, heat exchange towers :using gas and liquid contact surfaces may be either blow-through or pull-through units In .a countercurrent blow ihrough unit, a tan assembly is conventionally attached to the tower to discharge air Heretofore, difficulty around the connectherein below the contact surfaces. has been encountered with leakage tion of the fan assembly with the tower casing. ltis,

of course, desirable to eliminate this leakage and also to deliver air uniformly distributed across the contact surfaces.

It is an object of this invention to provide an improved evaporative heat exchange apparatus embodying gas and liquid cont-act surfaces which will enable more uniform fluid distribution across the contact surfaces and decreased resistance to gas flow. It is. another object of this invention-to provide an evaporative heat exchange apparatus comprising a vertical tower having a new and improved gas and liquid contact section comprising a plurality of sinuous sheets having straight vertical portions at the top and bottom ends thereof and spfiaced to provide a series of sinuous chan- .nels with straight inlets and outlets which promote better 3,132,190 Patented May 5, 1964 sectional tower having removable gas and liquid contact sections to permit the heat exchange capacity of the tower to be varibed without excessively increasing the resistance to the flow of gas through the tower.

It is a further object of this invention to provide an evaporative type heat exchange apparatus comprising a tower embodying gas and liquid contact surfaces and having a fan discharge conduit which extends a substan tial distance through the tower casing below the contact surfaces to eliminate leakage around the fan connection and achieve more efiicient operation.

It is a still further object of this invention to provide such an apparatus wherein the fan discharge conduit extends into the tower in a direction inclined downwardly from the horizontal to achieve more uniform distribution of gas across the gas and liquid contact surfaces.

These and other objects will become more apparent from the description of-the specific embodiments illustrated on the drawings and specifically described hereinafter.

In the drawings: I

FIGURE 1 is a view partially in front elevation and partially in section showing a blow-through cooling tower constructed in accordance with the invention;

FIGURE "2 is a vertical sectional view taken in the direction of the arrowsalong the line 2-2 of FIGURE 1;

- FIGURE 3 is a view partially in front elevation and partially in section showing an evaporative condenser tower constructed in accordance with the invention;

FIGURE 4 is a vertical sectional view taken in the direction of the arrows along the line 4-4 of FIGURE 3; 7 FIGURE 5 is a view partially in front elevation and partially section showing a pull-through type cooling tower constructed in accordance with the invention;

FIGURE 6 is a fragmentary perspective ing a portion of the contact surfaces constructed in accordancevwith the invention;

FIGURE 7 is a fragmentary perspective view showing details of the sectional construction of a cooling tower according to the invention;

FIGURE '8 is a fragmentary vertical sectional view showing in detail a joint between cooling tower sections; and

JFIGUR'E 9is a fragmentary vertical sectional view showing in detail an alternative form of a joint between the cooling tower sections. x

A vertical blow-through type coolingutower of rectangular cross section and embodying the invention is designated by the reference numeral 1. Itis to be understood, however, that the tower 1 may be constructed with a circular or any other suitable cross section. The tower 1 is formed with a pan section 3, two contact sections 4 and 5, and a spray section '6. However, it is to be understood that there may sections. As will be more fully described hereinafter, water is sprayed from the spray section v6 and descends downwardly by gravity 4. Air is forced upwardly through contact sections 4 and 5 in a countercurrent contact with the water. -It is, of course, also feasible to pass the air in co-cuirent'contact with the water. i i A Each contact section is formed with a casing made up of four box-shaped panels 7 assembled in the manner shown in detail in FIGURE 7 and connected together by means of self-tapping metal screws 8. As "shown in detail in FIGURE 8, each panel 7 has a lower flange'lt) and an upper flange 11 and adjacent contact sections are view showbe any number of contact through cont-act'sections 5 and connected together by means of self-tapping metal screws 9 which extend through the lower flanges 10 of one contact section and the upper flanges 11 of the next lower contact section. It is to be understoodthat bolts may be used instead of the screws 9. A gasket 12 of fiber or any suitable material is positioned between the

flanges

10 and 11 to seal the joint'between adjacent contact sections. The pan section 3 is enclosed by a rectangular outer casing 2 which is-provided-with a peripheral flange 13 connected to the lower flanges 10 of the bottom contact section 4 by a joint similar to that shown in FIG- URE 8. Similarly, the spray section 6 is provided with a rectangular outer casing 2a having aperipheral flange 14 at the bottom end thereof which is similarly connected to the upper flanges 11 of the top contact section 5. To "insure vertical alignment of each of the sections of'the cooling tower, flange 13 and each of the flanges 11 is provided with a series of guide pins 15 which fit into guide holes 16 in each of the

flanges

10 and 14.

- As best seen in FIGURES l, 2, and 6, each of'the contact sections 4 and 5 contains a plurality'of upright sinuious sheets 17 supported between

angles

21 and 22 which are attached as by welding or bolting to the backs of panels 7. The sinuous sheets 17 are spaced uniformly across the entire area of each contact section by spacer strips 18 which hang loosely from the top of each sheet '17 by hooks 19. If desired, however, the spacer strips 18 may be welded to the sheets 17 to provide a rigid unit. This spacing of the sinuous sheets 17 provides a series of sinuous channels 23 extending through each contact section in a generally vertical direction. The sinuous walls of' sheets 17 form contact surfaces along which water from spray section 6 flows downwardly. A forced draft of air passes upwardly through sinuous channels 23 in countercurrent contact with the water flowing over the surfaces of the sheets 17 resulting in rapid evaporation and reduction in temperature of the water.

Each sheet 17 has straight vertical portions 24 extending a substantial distance at the top and bottom ends thereof to provide straight vertical inlets and outlets for the channels 23 which straight portions constitute a particularly important feature of the invention. Without such straight portions, air passing upwardly through the contact section leaves the'channels at an angle with the vertical, thus having a tendency to blow the down-falling water laterally across the ends of the channels. This creates a damming efiect and the resistance to air flow'is thereby greatly increased. A further effect of the water being blown laterally is that it will not be distributed evenly across the top of the-contact section. The straight portions 24 must be long enough to allow the air flow to straighten out and leave the channels 23 in a vertical direction. Thus, the water Wlll not be blown laterally, but will be evenly distributed across the contact section and the damming effect will be eliminated. Further, the water flowing through each channel 23 will be evenly distributed between the surfaces on each side thereof. The resistance to air flow is greatlydiminished; higher air velocities maybe obtained; and the efliciency of the contact surfaces is materially increased.

It is to be understood that only one contact section of any desired height or any number of contact sections of various heights may be utilized to provide a cooling tower of any desired capacity. When multiple contact sections are used,- it is desirable to vertically align the sheets 17 in each section so that the channels-23 in each section will be as nearly as possible extensions of the channels 23 in the adjacent section or sections to minimize the resistance to air flow through the multiple sections. As seen in FIGURES l and 5, the sheets 17 in contact section 5 are vertically aligned with the sheets '17 in contact section 4. I a 1 Water is delivered to the spray section through conduit 25 from which it passes through cross pipes 26 and is sprayed downwardly through spray nozzles 27 over the top of contact section 5. After passing through contact sections 5 and 4, the cooled water collects in the bottom of pan section 3 from which it may be removed through strainer 28 and conduit 29 to any desired point of use (not shown). From the point of use, the water may be recirculated through .conduit 25 and once again sprayed over the contact sections. However, if recirculation is not desired, fresh water may be supplied to conduit 25. Pan section 3 is also provided with drain outlet 31, overflow pipe 32, and inlet conduit 33 for makeup water. The flow ofmakeup water is controlled by valve 34 which is opened and closed by float 35 according to the level of water in pan section 3. In addition, access to the pan section may be gained through hatch 36.

To move a forced upward draft of air through contact sections 4 and 5, there is provided a fan assembly 37 which includes a fan housing 38. The fan is operated by a suitable motor 39 which may be electric. Motor 39 is mounted on motor platform 61 which is in turn bolted to a pair of vertical angles 62, one of which is shown, and a pair of inclined angles 63, one of which is shown. Secured to fan housing 38 is a fan outlet extension 42. his to be understood, however, that the outlet extension 42 may be an integral part of the fan housing. The motor platform 61, vertical angles'62, and inclined angles 63 form a supporting frame connected to and surrounding fan housing 38 and fan outlet extension 42. The connections may be either welded or bolted. The vertical angles 62 may then be bolted to angles 60, one of which is shown, attached as by welding to casing 2 with the outlet extension 42 positioned in the exterior end of fan discharge conduit 43 without being permanently fastened thereto. Thus, the entire'fan assembly 37 may be readily unbolted and removed from the side of the tower casing. If desired, a fan assembly consisting of multiple fans may be utilized.

The fan discharge conduit 43 is mounted in the casing 2 and connected thereto as by welding with a water-tight connection. The fan discharge conduit 43 extends into .the interior of pan section 3 a substantial distance in a direction inclined downwardlyfrom the horizontal. The construction and positioning of fan discharge conduit 43 is a very important feature of the invention. The air from the fan flows through the lower portion of fan housing 37 and fan outlet extension 42 in a pattern as indicated by the arrows 44. As a result, a low-pressure area 45 is formed at the junction of the fan outlet extension 42 with-the casing 2 of the pan section. This low pressure area 45 is, of course, formed adjacent to the low pressure side of the fan which,as shown in FIGURE 1, rotates on an axis extending laterally across the longitudinal axis of the conduit 43. The low pressure side of the fan is that on which the rotating fan blades are moving awayfrorn the conduit 43. On'the high pressure side of the fan, the blades are moving toward the conduit and thus the air flow from the fan is concentrated on the high pressure side, thereby causing the low pressure area at 45. Were it not for the fan discharge conduit 43, water descending from the contact sections would tend to back into the low-pressure area 45 and if a watertight connection between the fan outlet extension 42 and the casing 2 is not provided, leakage will result. When fan discharge conduit 43 which extends a substantial distance into the interior of the cooling tower 1 is provided, the air pressure becomes uniform across the area of the fan discharge conduit 43 at the interior end of the conduit. Thus, the outlet extension 42' may be merely slipped into the end of the. fan discharge conduit 43 and no leakage will result around the connection. Further, since the ,fan dischargeconduit 43 is inclined downwardly from the horizontal, the stream of air is directed toward the lowerend of pan section 3 and is dispersed by the surface of the water and the opposite side of casing 2.

t This dispersion coupled with the fact that'the air has a greater vertical distance to travel toward the contact sections 4 and 5 than if the fan discharge conduit were horizontal results in more uniform distribution of air across the area of the contact section 4. Another advantage of thisconstruction of fan discharge conduit 43 is that the cooling tower may be operated by using the water spray only with the fan turned off and there will be no backup of water into the fan'assembly 37. q

A plurality of eliminator blades 47 are supported in rectangular frame 46 across the top of spray section v6 of the cooling tower 1. ,Each eliminator blade 47 is stamped from a single sheet of metal and 'is' formed with a V-shaped protrusion'43 in the center of the blade and a lateral lip 49 extending from the upper end thereof at an angle normal to the plane of the body of the blade 47. This particular construction is particularly advantageous in that each blade 47 may be formed by a single stamping of a flat sheet of metal. The blades 47 are uniformly spaced across the 'top of the tower 1 forming tortuous channels 51. The air which has passed through contact sections 4 and5 has droplets of water entrained therein when it'enters the tortuous channels 51. The eliminator blades decrease the velocity of the air and deflect the entrained water downwardly once again to the contact sec- 7 tions in a manner well known in cooling towers.

In FIGURE 9, there is disclosed an alternative form of the joint shown in FIGURE 8.

In this embodiment, gasket 12 is eliminated and the flanges and 11' are abutted against one another. A U-shaped member 52 is slipped over the outside of flanges 1t) and 11 and bolted 30 thereto by means of bolts 53. A sealing compound 54 of any commercially available type is placed against the interior surface of the bend 55 in U-shaped member 52 to seal the joint between

flanges

10 and 11.

Shown in FIGURE 5 is an alternative embodiment of the invention which constitutes a pull-through type cooling tower 70. It is provided with a pansection 77,

contact sections

71 and 72, spray section 73, and fan section 74. The sections are connected together in the same 7 manner as are the corresponding

sections

3, 4, 5 and 6 of cooling tower 1 as fully described hereinbefore. There is schematically shown a fan assembly 75 which is supported within fan section 74. Pan section 77 is provided with an air intake 76, and air is moved upwardly through the

contact sections

71 and 72 by the fan 75. Except for the position of the fan, the construction and operation of the pull-through type cooling tower 70 is like that of the blow-through type tower 1. i

Illustrated in FIGURES 3 and 4 is an evaporative condenser tower 64 according to the invention which includes a pan section 65, a cooling coil section 56, and a spray section 66 which includes eliminator blades 69. The pan section 65 and the spray section 66 have interior constructions identical with those of the pan section 3 and the spray section 6 of the cooling tower 1. Further, there is mounted'on the side of the evaporative condenser tower a fan assembly 67 identical in all respects with fan assembly 37. Fan assembly 67 discharges into fan discharge conduit 68 which is identical in all respects with fan discharge conduit 43. The cooling coil section 56 embodies a plurality of cooling coils 57 in which a refrigerant may be condensed from a gaseous to a liquid form or any fluid may be refrigerated by the reduction in temperature resulting from the rapid evaporation of water during countercurrent flow of waterand air across the interior surfaces of the cooling coils.

There has been illustrated and described what is considered to be the preferred embodiments of the invention. It will be understood, however, that various modifications V may be made without departing from the broader scope of the'invention as described by the following claims.

What I claim is: 1

1. Gas and liquid contact apparatus comprising a vertically extending tower having a side wall, means insaid tower presenting a surface for receiving liquid to have heat evaporatively extracted therefrom, means to flow water by gravity over said surface presenting means, means spaced vertically below said surface presenting means'and within the tower for receiving the water falling from the surface presenting means, a fan for flowing air upwardly through said surface presenting'means counter to the flow of said water, said fan being located adjacent to but outside of said tower, said fan having an output side, an imperforate duct extending from the output side of said fan through the wall of said tower to a region located substantially within the confines of the periphery tally at least as far as the lower extremity thereof at said mouth so that the month does not face into the water falling from the surface presenting means to the water receiving means.

2. Gas and liquid contact apparatus, comprising a vere tically extending tower having a side wall, means in said tower presenting a surface for receiving liquid to have heat evaporatively extracted therefrom, means to flow water by gravity over said surface presenting means, means spaced vertically below said surface presenting means and within the tower for receiving the water falling from the surface presenting means, a fan for flowing air upwardly through said surface presenting means counter to the flow of said water, said fan being located adjacent to but outside of said tower, said fan having an output side, an imperforate duct extending from the output side of said fan through the wall of said tower to a region located substantially within the confines of the periphery of said tower above said water receiving means and below said surface presenting means and terminat-' ing by defining an open mouth, the portion of said ducting within said tower lying wholly below a horizontal plane at'the level of the uppermost edge of the ducting at its point of passage through said wall of said tower,

This application is a continuation of my application 7 Serial Number 552,080, filed December 9, 1955, now abandoned.

the upper extremity of the ducting at said mouth extending horizontally at, least as far as the lower extremity thereof at said mouth so that the mouth does not face into the water falling from the surface presenting means to the water receiving means, said ducting being of greater cross sectional area at said mouth than, at the point of passage through said wall of said tower.

3. Gas and liquid contact apparatus comprising a vertically extending tower having a side wall, means in said tower presenting a surface for receiving liquid to have heat evaporatively extracted therefrom, means to flow water by gravity over said surface presenting means, means spaced vertically below said surface presenting means and within the tower for receiving the water falling from the surface presenting means, a fan for flowing air upwardly through said surface presenting means counter to the flow of said water, said fan being located adjacent to but outside of said tower, said fan having an output side, an imperforate duct extending from the output side of said fan through the wall of said tower, said surface presenting means and terminating by defining an open mouth, the upper extremity of'the duct at the mouth extending horizontally at least as far as the lower extremity thereof at the mouth so that the mouth does not I face into the water falling from the surface presenting means to the water receiving means.

4. Gas and liquid contact apparatus comprising a vertically extending tower having a side wall, means in said tower presenting a surface for receiving liquid to have heat evaporatively extracted therefrom, means to flow water by gravity over said surface presenting means, means spaced vertically below said surfacepresenting means and within the tower for receiving the water falling from the surface presenting means, a fan for flowing air upwardly through said surface presenting means counter to the flow of said water, said fan being located adjacent to but outside of said tower, said fan having an output side, an imperforate duct extending from the output side of said fan through the wall of said tower, said ducting sloping downwardly from the point of passage through the wall of said tower to a region located substantially within the confines of the periphery of the tower above said water receiving means and below said surface presenting means and terminating by defining an open mouth, the upper extremity of the duct at the mouth extending horizontally at least as far as the lower extremity thereof at the mouth so that the mouth does not face into the water falling from the surface presenting means to the water receiving means, said ducting being:

of increasing cross sectional area in the direction of said mouth so that the velocity of the gas just before leaving said mouth is reduced with an accompanying increase in static pressure.

UNITED STATES PATENTS Dame June 17, Miller Feb. 20, Wiedeman ..1 Sept. 4, vBrassert et a1. Feb. 22, George Dec. 9, Kennedy May 4, Lakin 1 Dec. 1, White Mar. 31, Samels Apr. 14, Roche et al. Jan. 7, Rupp Oct. 24, 1 Miles July 22, Stutz Feb. 21, Miller Aug. 1, Geneck Nov. 28, Simpson L Sept. 30, Baker Dec. 22, Miller July 3, Kahl Mar. 5, Miller et a1 Oct. 8,

FOREIGN PATENTS France June 19,

Claims

1. GAS AND LIQUID CONTACT APPARATUS COMPRISING A VERTICALLY EXTENDING TOWER HAVING A SIDE WALL, MEANS IN SIDE TOWER PRESENTING A SURFACE FOR RECEIVING LIQUID TO HAVE HEAT EVAPORATIVELY EXTRACTED THEREFROM, MEANS TO FLOW WATER BY GRAVITY OVER SAID SURFACE PRESENTING MEANS MEANS SPACED VERTICALLY BELOW SAID SURFACE PRESENTING MEANS AND WITHIN THE TOWER FOR RECEIVING THE WATER FALLING FROM THE SURFACE PRESENTING MEANS, A FAN FOR FLOWING AIR UPWARDLY THROUGH SAID SURFACE PRESENTING MEANS COUNTER TO THE FLOW OF SAID WATER, SAID FAN BEING LOCATED ADJACENT TO BUT OUTSIDE OF SAID TOWER, SAID FAN HAVING AN OUTPUT SIDE, AN IMPERFORATE DUCT EXTENDING FROM THE OUTPUT SIDE OF SAID FAN THROUGH THE WALL OF SAID TOWER TO A REGION LOCATED SUBSTANTIALLY WITHIN THE CONFINES OF THE PERIPHERY OF SAID TOWER ABOVE SAID WATER RECEIVING MEANS AND BELOW SAID SURFACE PRESENTING MEANS AND TERMINATING BY DEFINING AN OPEN MOUTH, THE PORTION OF SAID DUCTING WITHIN SAID TOWER LYING WHOLLY BELOW A HORIZONTAL PLANE AT THE LEVEL OF THE UPPERMOST EDGE OF THE DUCTING AT ITS POINT OF PASSAGE THROUGH SAID WALL OF SAID TOWER, THE UPPER EXTREMITY OF THE DUCTING AT SAID MOUTH EXTENDING HORIZONTALLY AT LEAST AS FAR AS THE LOWER EXTREMITY THEREOF AT SAID MOUTH SO THAT THE MOUTH DOES NOT FACE INTO THE WATER FALLING FROM THE SURFACE PRESENTING MEANS TO THE WATER RECEIVING MEANS.