US2117411A - Evaporative condenser - Google Patents

Description

May 17, 1938. F R ERBACH 2,117,411

EvAPoRATIvE coNDENsER Filed Dec.V 4, 1956 s sheets-sheet 1 May 17, 1938. F. R. ERBACH EVAPORATIVE CONDENSER Filed Dec. 4,- 195e 5 Sheets-Sheet 2 WIA IINIM zw@ .JW w f /WV mw mm @n 1 l 1 i j ,ww 6 T l# J L.. uw

mwN

May 17, 1938. F, R, ERBACH 2,117,411

EVAPORATIVE CONDENSERA Filed Dec. 4, 1956 5 Sheets-Sheet 5 niet ay l?, 1938 aiu-,4u

EVAPEA CUNDENSER F llt. Erbach, Beloit, Wis., assigner to General Reirigeration Corporation, Beloit, Wis., a corporation oi Delaware Application ember d, 1936;. Serial No. lldtll *i cui. (ci. asv-.svi u lilac invention relates generally to the art of rchieeration with more particular reference to improvements in apratus for cooling condenser coils by the evaporation of moisture, thereby' rapa idly removing heat from the condenser coils which may have a high temperature refrigerant gas or other high temperature gas orv liquid owing therethrh.

in a. refrigeration machine the hot discharge l@ gas tro the compressor must be cooled in order to condense the refrigerant and return it to the receiver m a liquid. The heat may be removed by means of air as in an air cooled condenser, by

means ci waterv flowing through a water cooled id condenser in which the water temperature is raised, or by evaporation of water, in which case both air and water are used as the means for removing the heat from the condenser coils.

object oi the invention is to provide an im- Zo proved evaporative condenser having increased emciency which is attained by thoroughly mimng o the air and water and properly distributing the mixture over the ace of the condenser coils lwhere evaporation takes place.

2e Another object ci the invention is to provide an evaporative condenser wherein the motor for operating the ian and water pump is mounted vertically above the tank, thereby eliminating pacliing boites, bearings, or ittings below the so water level in the tanh which might leak or be the cause ci serious trouble.

Another object ot the invention is to provide an evaporative condenser vhaving a pump of the simplest rotative cone design in which water enas ters at the bottom inlet of the cone and is deilected upwardly until it reaches the mouth of the cone, whereupon it is discharged by centrifugal force across the air streams entering the ian. y this arrangement thorough mixing oi the air u@ and moisture as it passes into the fan is secured.

Another object of the invention is to provide an proved arrangement of r condenser coils wherein the high temperature gases are intro' duced through a header at the outside of the 45 condenser coils, which consist of a series ofilat spirals of copper tubing connected in parallel to sin ide-header forming the outlet for the condenser. According to the invention as the spirals progress toward the center of the coilthey have a 5o downward pitch, permitting the condensed refrigerant liquid or other liquid to drain inward toward the outlet header'. The arrangement also results in accomplishing the counter-flow principle in heat exchange. The hot discharged gas is fed 55. in at the outside of the condenser and as it proa result oi the evaporation oi water.

grasses toward the center itis cooled. Thus the condenser liquid is cooled to the minimum inlet airtemperature and the outlet discharge air temperature is raised to the maximum degree pos sible.

The invention is also concerned. with the provision oi an evaporative condenser wherein the condenser surfaces can be readily cleaned to remove the hard deposits which adhere thereto as Practically 1o all water is hard and contains minerals which may cause an encrustation over the surface ci the condenser. The condenser coils of the present evaporator are mounted in a tank that can be Hooded to submerge the coils in a cleaning sol5 lution of the proper chemical analysis for dissolving the particular type of mineral deposits left on the coils by the evaporatlng water. d special K valve is provided by means oi. which the water level may be changed from the normal operating 2o level to the Hooded level for cleaning purposes and which may be opened for drag the tank after completion of the cleaning process.

With these and various other objects in view, the invention may consist of certain novel iea- 2e tures ci construction and operation, as will be more fully described and particularly pointed out in the specication, drawings and cl in. appended hereto. s

In the drawings4 which illustrate an embodi- 36 ment of the invention and wherein like referenceA characters are used to designate lilre parts--V Figure li is an elevational view, parts being shown in section, oi the evaporative condenser embodying the features of the invention; `as

Figure 2 is a top plan view of the evaporativev condenser of Figure l with the cover plate for the .tank and fan motor removed, and

Figure 3 is an end elevational view oi the evaporator looking toward the left in Figure 1. 4o

In the embodiment of the invention selected 'for illustration in the drawings, the operating parts of the present evaporator are supported upon a table having a top I0 substantially rectangular in plan and which in turn is supported 45 on any suitable foundation by means of theuprights Il having circular foot rests I2. Suspended by means of U-shaped rods I3 from the table top I0 is a cylindrical tank I4 forming the receiver for the liquid medium after the same has 50 been condensed by the condensing structure to be presently described. 'Ihe respectiyeends of l, the rod I3 are secured by `nuts I6 to the .brackets I6 which are fastened asv by welding to tha-'undersuriace of the-top plate I0.

The top plate I0 comprises the bottom of the tank which is formed by the cylindrical side wall I1 welded to said top plate so as to form a uid tight connection therewith. The top member of the tank comprises a removable cover I8 having a depending ange I3 adapted vto Viit within the cylindrical wall I1 of the tank and thus properly positions the cover thereon. Suitably secured to the exterior orf the cylindrical wall I1 of the tank are upwardly projecting pins 28 adapted to pass through openings formed in the cover and receive screws 2i, thereby releasably securing the cover in place. Said cover has formed integral therewith upwardly extending lugs 22 which form supports for plate member 23, the same being releasably secured thereto by the threaded screws 24, the rubber inserts 25 being interposed therebetween in order to cushion the -vibrations of the motor 28 supported by said plate member. The rotor shaft v21 of said motor extends centrally through the opening 28 in the cover I8 formed by the downwardly curved Walls 28 and attached.

to the lower end thereofby the connecting webs 38 is a pump tube formed by the inverted cone 3l. Said pump tube carries the centrifugal fan designated generally in Figure 1 by numeral 32 and which consists of a base member 33 supporting a plurality of radial plates 34.

Located within the tank I1 and positioned substantially concentric with the centrifugal fan are a plurality of condenser spirals 36 each having connection at its outer end to a supply header 31 and connecting at its inner end to an outlet header 38. Each header extends upwardly through the base I0 of the tank and is positioned with respect to the other header so as to give each spiral a downward pitch as thespirai progresses from the header 31 to the outlet head er 38. Asa result oil in the high temperature Sas flowing through the condenser spirals and the condensed liquid will drain inward toward the outlet header. 'I'he spaced vertical rods 39 maintain the spiral coilsin proper superimposed relation. 'I'hree sets of theserods are used, each set being retained in spaced relation by the top member 40 which is heldlagainst the rods by the screw 4I having threaded connection with cover I8. The header 31 is joined to a supply pipe 42 by which high temperature refrigerant gas or other high temperature gas or liquid may be delivered to said header and thus to the spiral coils connecting therewith. In

a like manner tlfe outlet header 31 connects with an outlet pipe 43 which discharges in to the re'- ceiver I4, the same being connected thereto by the member 44.

I'he space between the cover I8 and the plate member 23 forms the air inlet for the centrifugal fan, air being drawn through said space and through the central opening 28 in saidcover and being delivered thereby to said fan. The duct 45, substantially rectangular in cross section, comprises the air outlet for said tank, said duct having a tangential connection therewith, as will be clearly understood! by reference to Figure 2. Water is supplied to said tank for cleaning or 'ilushing purposes by the water pipe 48 which.

passes throughthe side wall of the duct 45 so as to discharge within said duct, said discharge end of the pipe being suitably secured to the wall f by nuts 41. Joined tov the water main 48 is a valved connection 48, regulated by handle 48,

and which lis provided with tubel connecting with a oat operated valve 5I, suitably located within said tank. The outlet 52 from said valve,

`like adhering thereto as a result of the evaporation of water by said coils. For'this reason the present tank is constructed so that the air inlet and the air outlet will be above the water level in the tank during the cleaning operation. The flood level of the water is determined by the overflow connection 58 joined by pipe 51 to connection 58, having valve therein. This last mentioned] connection determines the normal level of the water within the tank.

During operation of the structure above de` scribed the pump tube 3| will dip into the water in the bottom of the tank since the normal water level, as determined by voutlet 88, will be slightly above the -lower end of .said pump tube. When the motor 28 is started, causing rotation of the fan, water is caused to ow up the pump tube 3l and to be discharged radially in a ne spray from the upper end of said pump tube. .Ac-`

cordingly, the fine water sprays are directed across the path of the air being delivered to the fan. 'Ihe pumping action of the inverted cone 3I is dependent on skin friction and the centrifugal force of the water on the interior wall of the inverted cone. The water escapes from the end of said pump tube in a substantially horizontal spray ,and moisture together with air is accordingly delivered to the blades of the fan. The discharge from the fan-therefore comprises air having moisture uniformly distributed throughout and which is directed against the said spiral coils 38 of the condenser. Moisture in finely divided form impinges on the condenser coils 38 surrounding the fan and as said coils are at a high' temperature, dueto the high temperature medium such as refrigerant gas flowing therethrough, evaporation readily takes piace. The evaporation of the water or moisture by the coils abstracts considerable heat from the medium flowing through the coils: This dissipation of heat by the coils takes place rapidly, thus condensing the medium as the same progresses toward the outlet header. The present evaporative condenser operates at -a high eillciency since the water consumption isv a minimum i'or the quantity ofheat dissipated. 'I'he method of cooling the condenser coils by the evaporation of moisture delivered to the `coils uniformly by air streams passing thereover and carrying the moisture in suspension isL more eii'ective and more economical than cooling by air or by water only. -The compressor discharge gases or other gas or liquid is delivered to the condenser through the header 31 located to the outside of the condenser and therefore said medium must flow inwardly toward the center ofthe spiral coils. However. the direction of the air and water mixture delivered by the fan is. :lust opposite the same flowing from the center toward the periphery of the condenser coils. This arrangement results in accomplishing the counter-now principle in heat exchange. As a result the refrigerant gas or other medium is condensed and is cooledl to theminimum inlet air temperature while/the discharge air temperature is raised to the maximum degree possible.

Another feature of the present condenser resides in the downward pitch of the spiral coils as they progress toward the outlet header 38.

This facilitates the iiow of the condensed liquid toward the outlet header.

A serious problem in a condenser of the above type is that of cleaning the evaporating surfaces which become coated with deposits left from the water evaporated. In the present structure the tank can be flooded to submerge the coils in a cleaning solution of the proper chemical'analysis to dissolve the particular type of mineral deposit left on the coils by said evaporation. This ilooding of the coils is made possible by locating the air inlet opening and air discharge opening above the upper level of the coils. For the cleaning operation the motor 26 is stopped and valve 60 is 4 closed. Water from `the water main 46 is then admitted to the tank by opening the valve in said main controlled by handle 62. The, water will ll the tank to a level determined by the overflow connection 56. For cleaning the condenser coils whenever the hardness in the water is largely calcium bicarbonate hardness, hydrochloric acid has been found satisfactory. 'I'he proper quantity of acid is added to the Waterv in the tank after the coils are completely submerged. During the cleaning operation the solution may be stirred occasionally or the process can be speeded up by iiowing a high temperature medium through the coils in order to heat the solution. At the end of the cleaning operation the drain I is opened to completely drain the solution from the tank.

The invention is not to be limited to or by details of construction of the particular embodiment thereof illustrated by` the drawings, as various other forms of the device will of course be apparent to those skilled in the art without departing from the spirit of the invention or the scope of the claims. 'A

What is claimed is:

1. In an evaporative condenser, in combination, a tank`providing a reservoir for water, a cylindrical fan mounted for rotation on a vertical axis and located in the upper end of said tank, means rotating with the fan for drawing water from said reservoir and discharging the same radially from the center of said fan, means located above said fan delivering air thereto, a plurality of condenser -coils encircling said fan and located in the path of said water and air mixture discharged by said fan, and an outlet for said air located above the level of said condenser coils, whereby said tank may be substantially filled with water to submerge the condenser coils in order to clean said coils.

2. In an evaporative condenser, the combination with a tank forming a reservoir for water, of a plurality of condenser coils supported within said tank, a motor operated fan positioned centrally of said coils and operating to discharge a water and air mixture over said coils, and an air supply opening and an air discharge outlet located above the level of said coils, whereby said tank may be substantially iilled with water to submerge said coils in order to permit cleaning charge outlet located above the level of said condenser coils, whereby said tank may be substantially lled with water to submerge said condenser coils for the purpose of cleaning said coils, and means for completely draining said tank.

4. In an evaporative condenser, the combination with a tank forming a reservoir for water, of a plurality of condenser coils supported within said tank, a motor operated fan positioned centrally of said coils and operating to discharge a water and an air mixture over said coils, an air supply inlet positioned above said fan, an Aair discharge outlet located above the level of said condenser coils, whereby said tank may he substantially lled with water for submerging said condenser coils, an overow connection for said tank determining the level of the water when said coils are submerged, and means for completely draining said tank.

:FRED R. ERBACH.

Images