Air cooled atmospheric heat exchanger

• US 4,119,140 A
• Filed: 11/23/1976
• Issued: 10/10/1978
• Est. Priority Date: 01/27/1975
• Status: Expired due to Term

• Current Assignee: MC Acquisition Corp. (M/C Holding Corp.)
• Original Assignee: The Marely Cooling Tower Company
• Inventors: Cates, Robert E.
• Primary Examiner(s): Myhre, Charles J.
• Assistant Examiner(s): Richter, Sheldon
• Application Number:
  US05/744,391
• Time in Patent Office: 686 Days
• Field of Search: 165/115, 165/166, 165/67, 165/172, 165/178, 165/DIG. 8, 165/DIG. 1
• US Class Current: 165/67
• CPC Class Codes: F28B 1/06 using air or other gas as the cooling medium
• CPC Class Codes: F28C 1/14 comprising also a non-direct contact heat exchange
• CPC Class Codes: F28C 2001/145 with arrangements of adjacent wet and dry passages
• CPC Class Codes: F28F 21/065 the heat-exchange apparatus employing plate-like or laminated conduits
• CPC Class Codes: Y02B 30/70 Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating
• CPC Class Codes: Y10S 165/182 Indirect-contact cooling tower
• CPC Class Codes: Y10S 165/90 Cooling towers
• CPC Class Codes: Y10S 165/905 Materials of manufacture
• CPC Class Codes: Y10S 261/11 Cooling towers

Abstract

A low cost, preformed, synthetic resin, indirect air cooled atmospheric heat exchanger especially adapted for use in water cooling towers is provided which exhibits enhanced water cooling properties notwithstanding fabrication thereof from relatively inexpensive, corrosion-free polyvinyl chloride or like materials heretofore thought to have insufficient heat conductivity for practical use in heat exchangers. These improved results stem principally from the use of a plurality of spaced, elongated, hollow, open-ended, thin tube-like hot water receiving structures having vacuum-formed sidewalls configured with a multiple-chevron corrugation pattern to rigidify the exchanger and present series of continuous, vertically extending serpentine paths which maximizes the prime heat exchange area of the sidewalls and causes the descending water to follow the tortuous internal sidewall flow paths to slow the descent of the water and thereby facilitate cooling thereof; moreover, the corresponding, undulating outside wall surfaces of the exchanger increase the turbulence of external cooling air currents flowing therepast to further enhance the overall cooling efficiency of the exchanger. The latter is advantageously positioned below a hot water distribution basin so that quantities of air are siphonically entrained within the descending water to further slow the travel thereof through the exchanger and also preclude build-up of the normally slight, negative pressures therewithin to a level sufficient to collapse the relatively thin sidewalls of the exchanger. In preferred forms, the exchanger is fabricated from a plurality of elongated, inverted, substantially U-shaped, preformed members interconnected along respective vertical margins to present a pack adapted to be tensionably supported in a water cooling tower structure. In addition, the packs are nestably stackable to permit easy installation and use thereof in a variety of cooling tower applications, for example in those employing both a wet and dry fill in combination.

Claims

1. Heat exchange apparatus for cooling a hot liquid with ambient derived air comprising:

a plurality of imperforate, initially generally rectangular, thermally conductive, synthetic resin sheets rebent upon themselves to present individual transversely U-shaped structures which are oriented in upright, inverted, juxtaposed disposition in use with adjacent structures being joined to present a heat exchange pack,

the upright sidewalls of each structure being located in horizontally spaced disposition, joined at the upper ends thereof by overlying, integral top bight portions, and presenting essentially upright air passages for horizontal flow of ambient derived air therethrough which enters respective structures of the pack at one upright, open end face of each of the structures below respective top portions and exits from the upright, open opposite end face thereof,

the upright sidewalls of adjacent structures also being in horizontally spaced relationship with means being provided to interconnect and seal the upright, adjacent side margins only of proximal structures for preventing loss of liquid along substantially the entire longitudinal lengths thereof to cause the sidewalls of adjacent structures to define upright, essentially horizontally extending open top and open bottom liquid conveying liquid passages therebetween which alternate with the air passages and allow liquid delivered to the open tops of the liquid passages to gravitate downwardly therethrough in heat exchange relationship with air moving in crossflow relationship thereto through said air passages and with the cooled liquid discharging from the open bottoms of the liquid passages,

each of said sidewalls being provided with integral projecting segments which extend into the liquid receiving passages to increase the flow path of liquid gravitating downwardly on the surfaces of respective sidewalls and also extending into the area between the sidewalls presenting each air passage for imparting turbulence to the air flowing through corresponding air passages; and

elongated, horizontal support elements extending beneath a sufficient number of the top bight portions of the heat exchange structures in load bearing relationship thereto to fully support the pack without significant deformation at the temperature of the liquid supplied to the pack and under the liquid load thereon.

2. Heat exchange apparatus as set forth in claim 1, wherein said segments extending into the liquid and air passages include abutting knob-like projections on the opposed faces of the sidewalls of said U-shaped structures remote from the adjacent U-shaped structures for maintaining the spacing between said sidewalls.

3. Heat exchange apparatus as set forth in claim 1, wherein said proximal sidewalls of said respective structures are also interconnected along spaced, vertically extending ribs in order to divide said liquid passages into discrete sections.

4. Heat exchange apparatus as set forth in claim 1, wherein the corresponding interior and exterior faces of said sidewalls are provided with surface undulations presenting a tortuous path configuration.

5. Heat exchange apparatus as set forth in claim 1, wherein the sidewalls of said structures have sections presenting the open bottoms thereof which are configured to complementally nest within the open tops of the structures of another of said packs therebelow.

6. Heat exchange apparatus as set forth in claim 1, wherein said extensions from the sidewalls present a series of normally horizontally extending chevron patterns which are configured to define continuous, tortuous, vertically extending paths.

7. Heat exchanger apparatus as set forth in claim 6, wherein the angle of inclination of the chevron corrugations on said opposed structure-defining sidewalls are in different directions whereby the crossing flow vectors of the descending liquid impart substantially vertical flow characteristics thereto as the liquid is discharged from said structures.

8. Heat exchange apparatus as set forth in claim 1, wherein the synthetic resin sheets defining said sidewalls are formed of relatively thin preformed synthetic resin material.

9. Heat exchange apparatus as set forth in claim 8, wherein said material is polyvinyl chloride.