US2384714A

US2384714A - Tubular heat exchanger

Info

Publication number: US2384714A
Application number: US524458A
Authority: US
Inventors: Villiger Eugen
Original assignee: Aktiengesellschaft fuer Technische Studien
Current assignee: Aktiengesellschaft fuer Technische Studien
Priority date: 1943-04-12
Filing date: 1944-02-29
Publication date: 1945-09-11
Anticipated expiration: 1962-09-11

Description

E. VlLLlGER TUBULAR HEAT EXCHANGER Sept. 11; 1945.

Filed Feb. 29, 1944 2 Sheets-Sheet l I'nu erfl-or Eugen Villiger APcornegs Sept. 11, 1945. E. VILLIGER TUBULAR HEAT EXCHANGER Filed Feb. 29, 1944 2 Sheets-Sheet 2 Inverflror EugenVil'li er mifog AHornegs Patented Sept. 11, 1945 TUBULAR. HEAT EXCHANGEB Eugen Villiger, Zurich, Switzerland, assignor to Aktiengesellschai't Fuer Technischc Stndien, Zurich, Switzerland, a corporation of Switzerland Application February 29. 1944. Serial No. 524,458 In Switzerland April 12,1943

4 Claim.

This invention relates to a tubular heat exchanger, and .its object is to render the exchange of heat in such an apparatus more intense whilst involving only small lossses in pressure with regard to the media passing through, so that, for otherwise equal conditions, a smaller total heat exchanging surface sufiices compared with that of the heat exchangers hitherto built. For this purpose according to the invention the tubes of the heat exchanger are subdivided into groups by at least one division plate extending in the ngitudinal direction of the heat exchanger, and furthermore a number of perforated baiiie plates are slipped over the tubes. These plates are arranged obliquely to the axis of the tubes and they delimit channels on each side of the division p1ate,.the channels on the one side of said plate crossing the channels on the other side of the plate. Each of these channels is connected at one end by anasscciated opening in the partition plate to a channel situated on the opposite side of said plate, the effect being to produce an approximation of helical flow.

Two preferred constructional f rms of the subject matter of the invention are shown by way of example in the accompanying drawings in which:

Fig. 1 shows a longitudinal section on the line I-I, in Fig. 2 through a first embodiment.

Fig. 2 is a cross section on the line 11-11 in Fig. l and r Fig. 3 is a perspective view of the division plate and the related oblique baffle plates.

Fig. 4 is a horizontal longitudinal section on the line IVIV in Fig. 5 through a second embodiment.

Fig. 5 is a vertical cross section on the line V-VinFig.4.

Fig. 6 shows a single tube nest, on the tubes of which a number of perforated baiile plates have been fitted at an angle to the longitudinal axis of the tubes.

Fig. 7 shows a view of a part of a perforated baiiie plate. I

In Figs. 1 and 2 the numeral I denotes the pressure resisting shell of a heat exchanger. To this shell i covers 2 and 3 are fixed at either end. The numeral 4 denotes a branch of the shell i, through which one of the heat exchang-' subdivided into two groups A and B by a partition or division plate 1 extending in the longitudinal direction of me heat exchanger, but not up to the

covers

2, 3.

In Fig. 3 a part of this plate I is shown in a plan view. On the tubes 6 of the two groups A and B a number of

perforated baflie plates

8 and 9 are fitted. The

baflle plates

8 and 9 delimit channels on either side of. the division plate I, to which channels the medium supplied through branch 4 can flow unhindered. Seen in a plan view, the channels on one side of the division plate i cross those on the other side of said plate 1. Furthermore, each of these channels is connected at one end by an associated opening ID in the plate 1 to the inlet of another channel situated on the opposite side of said plate. In other words, the perforated baille plates 8 delimit channels which, with reference to Fig. 1,'extend from the upper left hand side diagonally to the lower right hand side, whilst the perforated bafile plates 9 delimit channels which extend diagonally from the upper right hand side to the lower left hand side. The size of the holes in

plates

8, 9, which holes are drilled obliquely to the frontal face of these plates, is suited as far as possible to the external diameter of the tubes 6, so that only a small quantity of medium can leak through said holes.

In a heat exchanger of the kind herein described the greater part of the medium supplied through branch 4 is canalized by the

baiiie plates

8 and 9 and caused to sweep over the tubes 8 obliquely, corners, in which the medium might stagnate, being avoided to the greatest possible extent. The

battle plates

8 and 9 compel the various partial currents to describe a zigzag course alternately on opposite sides of the division plate I, all currents of the medium flowing approximately the same lineal distance between inlet and discharge. This ensures the intense exchange of heat aimed at, so that with a minimum heat exchanging surface a maximum exchange of heat can be attained. At the same time the

perforated plates

8 and 8 serve as distance pieces for the tubes 6. This simplifies the design and reduces the manufacturing expenses, whilst it also ensures low losses in pressure since no additional distance pieces have to be installed.

To prevent the

bailie plates

8 and 9, slipped over the tubes, being forced out of position or warped during operation, they can be conveniently welded, soldered or otherwise attached to some of the tubes 6.

Since the flow guiding structure is composed of flat plates, the expense of manufacture is description. In these figures the numeral i2 denotesthe pressure resisting shell of the heat exchanger in which two branches l3 and H for the supply and outlet respectively of one of the heat exchanging media. are provided. Furthermore i5 denotes a distributor arranged transversely to the longitudinal axis of the shell 12 and extending through the latter; through this distributor it enters a second heat exchanging medium. The numeral [8 denotes a collector for the second medium, which is likewise arranged transversely to the longitudinal axis of shell i2 and through which the second medium leaves the heat exchanger. Distributor l5 and collector l6 are connected by the above mentioned tubes ll assembled intonests and by distributing pieces I8 and collecting pieces I! for these nests. The tube nests H are arranged in groups each comprising twosuperimposed rows, and each group of two rows is placed in a container I9, 20, 2i and 22 respectively. which is open at both ends. The container I9 is supported by a longitudinal frame 23, the container by a longitudinal frame 24 and the container 2| by a longitudinal frame 25, whilst the container 22 rests immediately on the pressure resisting shell l2. Each of the containers I9, 20, 2! and 22 is subdivided into two chambers by

respective division plates

26, 21, 28 or 29, as the case maybe, placed between the corresponding two rows of tube nests, the medium supplied through opening I3 having unobstructed access to' said chambers. By the provision of suitably shaped transverse intercepting plates 80 (Fig. 4) at least at one end of the containers I9, 20, 2! and 22 and by means of the

longitudinal frames

23, 24 and 25 it is possible to ensure that no medium flows through the chambers delimited by the external surfaces of the containers, the longitudinal frames and the pressure resisting shell l2. 7

Each tube nest comprises also a number of perforated baflie plates 3|. Since in this case the holes 32 to be provided in th'e plates 3| in order to permit of the tubes beingpassed through, are also drilled diagonally t0 the frontal side of the plates 3| (see Fig. '7); the plates 3| slipped over the tubes II are at a slant to the longitudinal axis of the nest. The size of the holes 32 in the plates 3| is again suited as far as possible to the external diameter of the tubes I I. All tube nests are of. equal length and each of them has an equal number of baille plates 3|, the distance between each two of such plates 3i being equal in all the tube nests. As a consequence when all tube nests have been inserted, the baille plates 8| delimit channels, which serve for guiding the medium supplied through opening l3. As shown in Fig. 4 also in this case the ch'annels on one side of a division plate, whenseen in a plan view, cross the channels on the opposite'side of the corresponding plate. In other words, the baflle plates 3! of the tube nests, which, for example, are situated in front of the partition 21 and are represented in Fig. 4 by the full. lines, delimit channels which extend diagonally from the upper right hand side to the lower left hand side,

whereas the baille plates ll situated behind the partition 21 and marked in Fig. 4 by hyphenated lines, delimit channels which extend diago from the upper left hand side to the lower right hand side. At the same time each channel is connected at itsend, which is always adiacent to a lateral container wall, through an associated opening, 1. e. a notch II provided in the corresponding division plate, with the inlet oi a channel situated on the opposite side of the plate. -In Fig. 4 th'ree such notches 38 are shown. The medium supplied through opening II is thus here also canalized by the baiile plates 3i and caused to sweep over the tubes ll of the various tube nests as a diagonal current and to take a generally helical or zigzag course above and below the corresponding division plate, all currents of the medium describing paths of approximately equal length.

For the application of the invention it is immaterial whether both heat exchanging media are gases. or whether one of same is a gas and the other a liquid, or whether both media are liquids. Thus tubular heat exchangers of the kind herein described can serve for heating or cooling gaseous or liquid working media, or heat conveying media and furthermore also for th'e condensation of vapours, the recooling of lubricating oil, etc.

What is claimed is: e

1. A baffling structure for heat exchangers of the shell and tube type in which the fluid flowing externally of the tubes enters adjacent one end of the shell and leaves adjacent theother, said baflling structure constraining said fluid to flow in a. generally helical path and comprising a flat plate which extends longitudinally of the shell between two sets of tubes and has notched lateral edges adapted to permit flow around the plate, and fiat plate-like oblique baflies located on opposite sides of said plate, the bailles on one side of the plate being reversely inclined with respect to those on the other and so arranged as to define paths communicating with sai notch'es.

2. The combination defined in claim 1 in which the oblique baflles are connected with at least some of the tubes by a fused metal connection. 3. A heat exchanger of the shell and tube typ including inlet and discharge connections for the fluid which flows externally of the tubes located adjacent opposite ends of the shell, longitudinal open ended sleeves embracing groups of tubes in said exchanger and defining segregated flow paths between, said inlet and discharge connections and a bathing structure in each of said sleeves, said baflling structures each comprising a flat plate which extendslongitudinally of the sleeve between tubes and has notched lateral edges to permit flow around the plate and fiat plate-like oblique baflles located on opposite sides of the said plate, the bailles onone side of the plate being reversely inclined with respect to those on the other and so arranged as to define paths communicating with notches.

4. The combination defined in claim 3 in which the tubes and their enclosing sleeves ex-. tend substantially horizontally, the sleeves sustaining the tubes by means of the respective baffling structures, there being supporting members carried by the shell of the heat exchanger and directly supporting the sleeves.

EU GEN vnmam.

corresponding