DE202008013351U1 - Heat exchanger network and thus equipped heat exchanger - Google Patents

Abstract

Heat exchanger network with a stack of mutually parallel first flow channels (5) for a hot medium and lying between them, also arranged parallel to each other second flow channels (6) for a cooling medium, wherein the first flow channels (5) through plates (2) and between them arranged longitudinal profiles (3) and the second flow channels (6) by plates (2) and between them arranged transverse profiles (4) are limited, wherein the first flow channels (3) in central areas with arranged therein turbulator inserts (12), the cooling capacity have increasing, laterally of flanks (14) limited passages, and in inlet and / or outlet areas with the mechanical strength increasing inlet or outlet profiles (22) are provided, the inlet or outlet channels (23) forming webs (27), and wherein the turbulators (12) and the inlet and / or outlet profiles (22) by soldering with which he Most flow channels (5) limiting plates (2) are connected, characterized in that the total thickness of all webs (27) of an entry or exit profile (22) s (min) * n (E) = (1.2)

Description

The The invention relates to a heat exchanger network according to the preamble of claim 1 and a heat exchanger with such a heat exchanger network.

Wärmeaustauschernetze This type are used in particular for cooling by first flow channels led, hot Medium, z. As of oil, compressed air or charge air of a motor vehicle, a construction or agricultural machine or a compressor plant, by means of a flowing through second flow channels Coolant, z. As air or water. To pose a problem in this case the temperature cycling loads and especially the dynamic ones Internal pressure changes with higher pressure, z. B. 8 bar and more, as this causes different stresses in the Heat exchangers occur. As special vulnerabilities especially those outside margins of the Heat exchanger network proven to which this usually by welding or the like. Firmly with the end plates of Collecting boxes connected to the feeder or discharge of the hot, the first flow channels serve flowing medium. Since the face plates of the Collecting boxes when operating with the high, to the outside directed internal pressure of the hot medium, be at least the solder joints or the flanks of the usual, immediately adjacent to the end plates, in the first flow channels arranged Turbulatoreinlagen additionally strongly on train claim. When cyclic alternating loads occur As a result, that said solder joints or flanks tearing the turbulator inserts, causing the heat exchanger is leaking.

To avoid this disadvantage, it is known in heat exchanger networks whose flow channels carrying the hot medium are designed as flat tubes ( DE 103 59 806 A1 ), the ends of the Turbulatoreinlagen or additional inserts, which are arranged in the ends of the flat tubes, by incisions or special, flexible corrugations in such a way that in the field of collecting tanks due to temperature changes occurring changes in length of the tubes are made possible. However, this requires additional operations in the manufacture of the heat exchange networks or specially shaped, stackable flexible insert body, which is not always desirable.

Furthermore, plate heat exchanger networks are known ( US Pat. No. 7,073,573 B2 ), in which the passages formed in the turbulator inserts are formed in the inlet regions with a greater pitch (smaller density) than in the central regions of the flow channels carrying the hot medium. This is intended to reduce the heat exchange of the hot medium with the turbulator surfaces in the inlet regions, thereby obtaining lower local heating and avoiding cracks in the solder seams and turbulator edges. The length of the Turbulatoreinlagen with reduced density of the passages should be 10% to 50% of the measured in the flow direction length of the first flow channels. This results in a considerable reduction of the heat exchanger performance.

Across from dynamic internal pressure loads are the solutions mentioned largely ineffective.

Finally, heat exchange networks of the type of interest here are known ( DE 298 22 888 U1 ), in which the Turbulatoreinlagen not, as usual, made of corrugated sheets, but made of extruded profiles with parallel elevations. Although such turbulator inserts increase the mechanical stability of the heat exchange networks, in particular also in the critical inlet regions, they also result in a great reduction of the heat exchanger performance due to a lack of swirling of the hot medium flowing through.

outgoing from this prior art, there is the technical problem of present invention, the heat exchanger network the genus mentioned at the outset and one equipped therewith Heat exchanger in such a way that in particular in the entry area, the probability of cracking in the Turbulatoreinlagen and their soldered seams reduced and thereby also against high internal pressure and temperature cycling loads an increased strength and thus an increased Life of the heat exchanger or heat exchanger network is obtained. In addition, the pressure to be accepted for and power losses remain small.

Solved This problem is inventively with the characterizing Features of claims 1 and 11.

The invention is based on the idea of providing the inlet and / or outlet ends of the flow channels carrying the hot medium with inlet profiles which are mechanically more stable than the turbulator inserts, preferably due to an increase in the overall thickness of their webs, but at most twice as large as the width of the second flow channels limiting transverse profiles. As a result, the inlet profiles are arranged only where there is still no significant heat exchange, so that the heat exchanger performance is only slightly reduced. In addition, the inlet and / or outlet channels be bordering webs of entry profiles are smooth and formed in the flow direction so that they cause virtually no turbulence of the medium flowing through, so that even through them, if the inlet and / or outlet channels to increase the mechanical strength overall smaller flow cross-section than the passages leave the Turbulatoreinlagen, the flow resistance of the heat exchanger network is at most slightly increased.

Further advantageous features of the invention will become apparent from the dependent claims.

The The invention will be described below in conjunction with the accompanying drawings explained in more detail in exemplary embodiments. Show it:

1 a perspective view of a heat exchanger with a heat exchanger network and two attached to this collection boxes;

2 schematically in a perspective and exploded view of an inventive design of the heat exchanger network of the heat exchanger according to 1 ;

3 a perspective view of a preferred embodiment of a turbulator insert for the heat exchanger network after 1 and 2 ;

4 a schematic longitudinal section through a part of the heat exchanger after 1 ;

5 and 6 Sections along lines VV and VI-VI of 4 through the heat exchanger network according to the invention;

7 to 11 various embodiments of inventive entry profiles in opposite 5 enlarged perspective views; and

12 to 16 further embodiments of inventive entry profiles in opposite 5 enlarged front views.

1 to 6 show a heat exchanger with a heat exchanger network, which is to be charged in particular with cyclic internal pressures and temperatures and is produced in conventional Plattenbauweise. The network 1 is from a plurality of plane-parallel, arranged in a stack and mutually parallel dividers or plates 2 composed. In the embodiment, the plates 2 rectangular in plan view, with long sides of the plates 2 one in the longitudinal direction of the network 1 measured length L, short sides of the plates 2 a depth T and one to the plates 2 vertical measure a width B of the heat exchanger network 1 determine. The plates 2 are according to 1 to 6 alternately by over the entire length L extended longitudinal profiles 3 and the whole depth T extended cross sections 4 kept at a distance. As a result, each forms a pair of superimposed plates 2 between one open at the front and the rear, laterally from the longitudinal profiles 3 limited, first flow channel 5 for a hot medium, e.g. As pressure or charge air, and one subsequent pair of plates 2 between them a front and rear open, laterally from the cross sections 4 limited, second flow channel 6 for a cooling medium, for. For example, air. The flow direction for the hot medium is in 2 indicated by an arrow X and the perpendicular direction of flow for the cooling medium by an arrow Y. The dimensions L, T and B are essentially determined by the desired performance of the heat exchanger.

In the 1 to 4 left ends of the first flow channels 5 form the inlet ends for the hot medium in the embodiment. This hot medium is by means of a connecting piece 7 a collection box 8th ( 1 ) supplied to from there the first flow channels 5 to flow in the direction of arrow X. The collection box 8th hood-shaped or box-shaped in a conventional manner and at its the net 1 facing side with a to the connecting piece 7 connected, in 1 only by a line 9 indicated cavity 10 ( 4 ), via which it communicates with the inlet ends of the first flow channels 5 communicates. In the 1 and 2 lying on the right, the outlet ends for the hot medium forming ends of the flow channels 5 are with a corresponding collection box 11 connected, which has a connecting piece, not shown, to supply the outflowing, cooled medium for further use.

In the first rounds 5 are between the associated plates 2 and longitudinal profiles 3 extended turbulator inserts 12 arranged, which serve in a known manner, on the one hand, the heat exchanging surfaces in the flow channels 5 on the other hand, to swirl the flowing medium, thereby increasing the overall heat exchange performance. For this purpose, the turbulator inserts 12 in particular 3 shows, with a variety of lateral flanks 14 limited, the first flow channels forming passages formed in known manner in heat exchangers from sheets, preferably a plurality of round or meandering (rectangular) curved corrugations with the lateral flanks 14 and upper and lower crest surfaces 15 . 16 exhibit. With special derem advantage, the corrugations in the direction of the length L are not continuous, but from several, in the direction of the depth T relative to each other staggered sections formed, whereby between these corrugations respectively slots 17 are formed. This allows the hot medium within the Turbulatoreinlagen 12 flow in the longitudinal and transverse direction, whereby it is intensively swirled and laminar flows are prevented, which is the heat transfer from the hot medium to the Turbulatorflächen and from there to the plates 2 significantly enlarged.

In the second flow channels 6 and between the plates delimiting them 2 and cross sections 4 are appropriate 2 and 4 usual, wavy lamellas 18 arranged, with their highest and lowest apex surfaces like the crest surfaces 15 . 16 the turbulator inserts 12 by soldering firmly to the plates 2 are connected. Like with brazed heat exchanger networks 1 is generally known, thereby not only improves the heat exchange performance, but also the plates 2 between the longitudinal and transverse profiles 3 . 4 be kept at a distance.

Incidentally, the described heat exchanger network 1 preferably an aluminum net, ie the plates 2 , the longitudinal and transverse profiles 3 and 4 , the turbulator inserts 12 and the slats 18 consist of aluminum or a Aluminiumlegie tion and are by conventional soldering, optionally using solder-plated plates 2 , to a stare, the net 1 forming block interconnected. Likewise, however, other heat exchanger materials such. As copper and its alloys or steel, especially stainless steel can be applied.

Heat exchangers, heat exchange networks 1 and turbulator inserts 12 of the type described are generally known to the person skilled in the art (eg DE 202 08 784 U1 . DE 296 22 191 U1 . DE 41 31 739 C2 ) and therefore need not be explained in detail.

The ends of the in 1 through the line 9 indicated and in 4 visible cavity 10 of the collecting tank 8th are through in 1 and 4 indicated end walls 20 closed, which consist either of separate parts, with a z. B. welded by extrusion molding box profile are welded, or are integrally connected by pouring the header box with this. In assembled condition ( 4 ) are these end walls 20 with an upper and lower end plate 21 the heat exchanger network 1 z. B. firmly connected by welding. This will in operation when the medium is in the cavity 10 under a high pressure of z. B. 8 bar and more, a corresponding pressure in the direction of 4 drawn arrows on the end walls 20 exercised. As a result, the plates 2 , especially the end plates 21 , the cross sections 4 and with them the Turbulatoreinlagen produced from comparatively thin sheets 12 additionally claimed to train. In connection with the usual alternating loads and the high temperatures of the hot medium, this leads to soldering seams and turbulator inserts in particular 12a ( 4 ), which are near the end walls 20 and end plates 21 lie, tear. In the area of cross profiles 4 is that still comparatively uncritical, has to the s.The lamellae 18 adjacent ends of the cross sections 4 However, the result is that the heat exchanger is leaking.

To avoid this problem, the invention provides, at least in the inlet ends of the end plates 21 near, first flow channels 5 one entry profile each 22 to arrange. These entry profiles 22 extend, as in particular 2 (top left) and 5 show, in the direction of the depth T over the entire area between the longitudinal profiles 3 and preferably connect to the cavity 10 bordering end surfaces of the transverse profiles 4 flush off. In the direction of the length L, the entry profiles extend 22 in contrast, only over an area that is approximately the width of the transverse profiles 4 corresponds, in particular from 2 and 4 is apparent. According to the invention, the width b (E) of the entry profiles is calculated according to the formula b (E) = (0.5... 2,0) .b (Q), where b (Q) is the width of the transverse profiles 4 is. Incidentally, the entry profiles 22 corresponding 5 with entrance channels 23 provided by the hot medium from the cavity 10 of the collecting tank 8th in the turbulator inserts 12 flowed through passages can flow.

According to a preferred embodiment of the invention are also for other sizes of entry profiles 22 preselected dimensions provided. This will be explained below with reference to 7 explained in more detail, in which the in 5 illustrated entry profile 22 is shown enlarged.

To 7 Contains the entry profile 22 a plurality of juxtaposed in the direction of the depth T, the inlet channels 23 forming, in the direction of the length L continuous recesses which alternately to an upper and lower broadside 24 respectively. 25 of the entry profile 22 boundaries, leaving the entrance channels 23 alternately upwards and downwards open edge sections 26 On the other hand, the inlet channels 23 laterally through as webs 27 limited edge portions limited, which may have different thicknesses depending on the contour of the recesses. The minimum thickness of these bars 27 is in 7 denoted by s (min). Besides, lets 7 recognize a measure t (E) that the division or the average distance of the webs 27 or recesses in the direction of the depth T indicates. If all one enters channels 23 have identically upwards or downwards open contours, t (E) is a fixed size. Are the contours of the entrance channels 23 varies in size, t (E) gives an average value for the division of the flow channels 23 at. Similarly, in 6 the thicknesses of the flanks 14 the turbulator inserts 12 with s (T) and the pitches of the turbulator inserts 12 , here denote the mean distances of two upper or lower cams in the direction of the depth T, denoted by t (T).

According to the invention, the minimum thickness s (min) of the webs 27 of the entry profile 22 preferably calculated according to the formula s (min) = (1.2 ... 2.0) * s (T) * n (T) / n (E), where n (T) is the number of edges 14 the turbulator inserts 12 and n (E) the number of bars 27 the entry profiles 22 is counted in each case in the direction of the depth T. An even further improvement in the mechanical stability of the heat exchanger network 1 can be achieved by selecting t (E) = (0.25 ... 0.45) * t (T) * s (min) / s (T). It then creates an entry profile 22 , on the one hand in the region of the inlet ends of the first flow channels 5 a rupture of the turbulator inserts 12 and the welds between the turbulator inserts 12 and the plates 2 At least greatly delayed in the entry area, on the other hand, despite possibly relatively thick webs 27 prevents a significant increase in the pressure losses of the hot medium. This is especially true when the outer walls of the webs 27 , as 7 shows, in the flow direction X are smooth and have no vortex-promoting agent.

• 1. Die Breite b(Q) der Querprofile 4 betrage 18 mm. Mit b(E) = (0,5 ... 2,0) b(Q) folgt daraus, dass b(E) einen Wert 9 mm bis 36 mm haben kann.
• 2. Die Tiefe T des Netzes 1 betrage 140 mm und die Dicke der Längsprofile 3 jeweils 7 mm. Dann beträgt die Tiefe T der Turbulatoreinlagen 140 mm – 2·7 mm = 126 mm.
• 3. Die Turbulatoreinlagen 12 besitzen die Maße s(T) = 0,3 mm und t(T) = 7,5 mm. Dann haben die Turbulatoreinlagen 12, in Richtung der Tiefe (T) gemessen, jeweils 16,8 Wellungen und, da jede Wellung zwei Flanken 14 umfasst, ist n(T) = 33,6 (vereinfacht = 33). Daraus folgt s(T)·n(T) = 9,9 mm, d. h. die Richtung der Tiefe T summierte Gesamtdicke aller Flanken 14 beträgt 9,9 mm.
• 4. Die Mindestdicke s(min) der Stege 27 des Eintrittsprofils 22 betrage 0,5 mm.
• 5. Mit der obigen Formel s(min)·n(E) = (1,2 ... 2,0)·s(T)·n(T) folgt daraus: s(min)·n(E) = (1,2 ... 2,0)·0,3 mm·33 = 11,9 mm ... 19,8 mm, d. h. die summierte Gesamtbreite aller Stege 27 des Eintrittsprofils 22 kann 11,9 mm bis 19,8 mm betragen im Vergleich zur summierten Dicke aller Flanken 14 der Turbulatoreinlage 12 von 9,9 mm.
• 6. Weiterhin ergibt sich aus der Gleichung s(min)·n(E) = 11,9 mm ... 19,8 mm wegen s(min) = 0,5 mm ein Wert n(E) = 23,8 ... 39,6, d. h. die Zahl der Stege 27 beträgt ca. 24 bis 40, in Richtung der Tiefe T gemessen.
• 7. Nach der oben ebenfalls angegebenen Gleichung soll gelten t(E) = (0,25 ... 0,45)·t(T)·s(min)/s(T). Mit den Werten nach 3) und 4) ergibt sich t(E) = (0,25 ... 0,45)·7,5 mm·0,5 mm/0,3 mm = ca. 3,1 mm ... 5,6 mm, d. h. die Teilung t(E) der Eintrittskanäle 23 bzw. Stege 27 im Eintrittsprofil 22 beträgt 3,1 mm bis 5,6 mm im Vergleich mit einer Teilung für die Durchgänge in der Turbulatoreinlage 12 von 7,5 mm. Da hier pro Teilung je zwei Flanken 14 vorhanden sind, beträgt der Flankenabstand 7,5 : 2 = 3,75 mm im Vergleich zum Stegabstand von 3,1 mm bis 5,6 mm bei den Eintrittsprofilen 22.

A practical embodiment has the following dimensions:

• 1. The width b (Q) of the cross sections 4 amount 18 mm. With b (E) = (0.5 ... 2.0) b (Q) it follows that b (E) can have a value of 9 mm to 36 mm.
• 2. The depth T of the network 1 140 mm and the thickness of the longitudinal profiles 3 each 7 mm. Then, the depth T of the turbulator inserts 140 mm - 2 · 7 mm = 126 mm.
• 3. The turbulator inserts 12 have the dimensions s (T) = 0.3 mm and t (T) = 7.5 mm. Then have the turbulator inserts 12 , measured in the direction of depth (T), each 16.8 corrugations and, since each corrugation two flanks 14 , n (T) = 33.6 (simplified = 33). It follows that s (T) * n (T) = 9.9 mm, ie the direction of the depth T summed total thickness of all edges 14 is 9.9 mm.
• 4. The minimum thickness s (min) of the webs 27 of the entry profile 22 amount 0.5 mm.
• 5. With the above formula s (min) * n (E) = (1.2 ... 2.0) * s (T) * n (T), it follows that: s (min) * n (E) = (1.2 ... 2.0) x 0.3 mm x 33 = 11.9 mm to 19.8 mm, ie the summed total width of all webs 27 of the entry profile 22 can be 11.9 mm to 19.8 mm compared to the summed thickness of all flanks 14 the turbulator insert 12 of 9.9 mm.
• 6. Furthermore, from the equation s (min) * n (E) = 11.9 mm ... 19.8 mm, because of s (min) = 0.5 mm, a value n (E) = 23.8 results. .. 39.6, ie the number of bars 27 is about 24 to 40, measured in the direction of depth T.
• 7. According to the equation also given above, let t (E) = (0.25 ... 0.45) * t (T) * s (min) / s (T). With the values according to 3) and 4), t (E) = (0.25 ... 0.45) · 7.5 mm · 0.5 mm / 0.3 mm = approx. 3.1 mm. .. 5.6 mm, ie the pitch t (E) of the inlet channels 23 or webs 27 in the entry profile 22 is 3.1 mm to 5.6 mm in comparison with a pitch for the passages in the turbulator insert 12 of 7.5 mm. Since there are two flanks per division 14 are present, the edge distance is 7.5: 2 = 3.75 mm compared to the web distance of 3.1 mm to 5.6 mm in the entry profiles 22 ,

Experiments with insert bodies of this type have shown that with pulse pressure loads of 1 to 15 bar with the entry profiles 22 provided heat exchanger networks 1 a lifespan about five times longer than heat exchange nets without inlet profiles 22 exhibit. It is expected that entry profiles 22 Whose overall web cross-section is chosen to be even greater than stated above will result in an even greater increase in the life of the heat exchanger network. It is also noteworthy that, when using the specified entry profiles 22 the pressure losses in the first flow channels 5 only about 6% worsened, while an effect on the performance of the heat exchanger could not be observed.

The entry profiles 22 can have many different shapes. As 8th shows, the open-edged, webs 28 forming inlet channels 23 instead of circular ( 7 ) also semicircular contours 29 or semi-oval contours. Next shows 9 a variant that consists of a meandering shaped metal sheet, the trapezoidally arranged webs 30 having. The division t (E) of the entrance profile 22 results here analogous to 7 through the mean distance between two inlet channels 23 , Next shows 10 an embodiment of an entry profile 22 with entrance channels 23 that in contrast to 7 to 9 are limited by completely closed edge sections. The entrance channels 23 have oval cross sections, but can also be provided with circular or otherwise rounded cross-sections. On the other hand shows 11 Finally, an embodiment analogous to 10 in which the completely closed entrance channels 23 however, have rectangular cross sections. Other square cross sections are possible here. From 8th to 11 apparent dimensions t (E) and s (min) for the webs 28 . 30 . 31 and 32 to 8th to 11 correspond in Übri according to those 7 ,

12 to 16 show the 7 to 11 essentially corresponding entry profiles 22 in front views, which is why the same reference numerals are used for the same parts. In contrast to 7 to 11 are the entry profiles 22 to 12 to 16 but at their the entrance channels 23 upper or lower limiting broadsides (eg 24 and 25 in 12 to 14 ) provided with outwardly directed, preferably convex-shaped bulges, ie formed spherical. This results when creating the entry profiles 22 to the flat surfaces of the plates 2 each wedge gaps, which ensure a large-area wetting of the parts with the solder during the soldering process. In the embodiments according to 15 and 16 These bumps can each be at the two the entrance channels 23 be formed above and below limiting wall sections.

The invention is not limited to the described embodiments, which can be modified in many ways. This applies in particular to the shape and dimensions of the turbulator inserts used in the individual case 12 and entry profiles 22 , It is clear that the quantities s (T) * n (T) and s (min) * n (E) are the sums of all thicknesses of the individual flanks 14 or footbridges 27 are to be calculated if they have different values in the direction of the depth T. In addition, all or only some of the first flow channels, in particular those near the end plates 21 lying flow channels 5 with the described entry profiles 22 be provided. Next it is possible, not only to the collection box 8th bordering entry ends, but also to the collection box 11 ( 1 ) adjacent outlet ends of the first flow channels 5 , with the described entry profiles 22 to be provided, which are expediently referred to in this case as outlet profiles and with the inlet channels 23 are provided corresponding outlet channels. Furthermore, constructions are conceivable in which the collecting boxes 8th . 11 not on opposite sides, but on the same side of the heat exchanger network 1 are arranged so that the hot medium is deflected only on the opposite side. Finally, it is understood that the various features can also be applied in combinations other than those described and illustrated.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 10359806 A1 [0003]
• - US 7073573 B2 [0004]
• - DE 29822888 U1 [0006]
• - DE 20208784 U1 [0024]
• DE 29622191 U1 [0024]
• - DE 4131739 C2 [0024]

Claims (14)

Heat exchanger network with a stack of mutually parallel first flow channels ( 5 ) for a hot medium and between these lying, also parallel to each other arranged second flow channels ( 6 ) for a cooling medium, wherein the first flow channels ( 5 ) through plates ( 2 ) and longitudinal profiles arranged between them ( 3 ) and the second flow channels ( 6 ) through plates ( 2 ) and between these arranged transverse profiles ( 4 ) are limited, wherein the first flow channels ( 3 ) in central regions with turbulator inserts ( 12 ), which increase the cooling capacity, laterally from flanks ( 14 ) have limited passages, and in inlet and / or outlet areas with the mechanical strength increasing inlet or outlet profiles ( 22 ), the inlet or outlet channels ( 23 ) forming webs ( 27 ), and wherein the turbulators ( 12 ) and the entry and / or exit profiles ( 22 ) by soldering with the first flow channels ( 5 ) bounding plates ( 2 ), characterized in that the total thickness of all webs ( 27 ) of an entry or exit profile ( 22 ) s (min) * n (E) = (1.2 ... 2.0) * s (T) * n (T), where s (min) is the minimum thickness of the webs ( 27 ) of the entry or exit profiles ( 22 ), s (T) is the thickness of the flanks ( 14 ) of the turbulator inserts ( 12 ), n (T) is the number of edges ( 14 ) of the turbulator inserts ( 12 ) and n (E) the number of webs ( 27 ) of the entry and / or exit profiles ( 22 ) mean. Heat exchanger network according to claim 1, characterized in that the inlet and / or outlet profiles ( 22 ) one in the direction of the turbulator inserts ( 12 have measured width b (E) satisfying the formula b (E) = (0.5 ... 2.0) * b (Q), where b (Q) is the width of the cross-sections (FIG. 4 ). Heat exchanger network according to claim 1 or 2, characterized in that the of the webs ( 27 ) of the entry and / or exit profiles ( 22 ) formed inlet and / or outlet channels ( 23 ) Have pitches satisfying the equation t (E) = (0.25 ... 0.45) t (T) * s (min) / s (T), where t (T) is the pitch of the flanks ( 14 ) of the turbulator inserts ( 12 ) and s (min) and s (T) have the meaning given in claim 2. Heat exchanger network according to one of claims 1 to 3, characterized in that the inlet and / or outlet channels ( 23 ) of the entry and / or exit profiles ( 22 ) are limited by completely closed edge sections. Heat exchanger network according to claim 4, characterized in that the inlet and / or outlet channels ( 23 ) have round, oval or rectangular peripheral contours. Heat exchanger network according to one of claims 1 to 3, characterized in that the inlet and / or outlet channels ( 23 ) of the entry and / or exit profiles ( 22 ) through to a page ( 24 . 25 ) open edge sections ( 26 ) are limited. Heat exchanger network according to claim 6, characterized in that the inlet and / or outlet channels ( 23 ) have semicircular or semi-oval outer contours. Heat exchanger network according to one of claims 1 to 3, characterized in that the inlet and / or outlet profiles ( 22 ) consist of corrugated or meandering shaped sheets ( 9 ). Heat exchanger network according to claim 6 or 7, characterized in that the inlet and / or outlet channels ( 23 ) alternately to one or the other side ( 24 or 25 ) of the entry and / or exit profiles ( 22 ) are open. Heat exchanger network according to one of claims 1 to 9, characterized in that the webs ( 27 ) of the entry and / or exit profiles ( 22 ) have smooth walls free of vortex-forming agents. Heat exchanger network according to one of claims 1 to 10, characterized in that with the plates ( 2 ) in contact broadside of the inlet and / or outlet profiles ( 22 ) are formed spherical. Heat exchanger network according to one of claims 1 to 11, characterized in that the widths limiting the inlet or outlet channels ( 24 . 25 ) of the entry and / or exit profiles are provided on their outer surfaces with convex curvatures. Heat exchanger with a heat exchanger network ( 1 ) according to one of claims 1 to 12, wherein the heat exchanger network ( 1 ) at the inlet and / or outlet ends of the first flow channels ( 5 ) with a collecting box ( 8th . 11 ) and with the inlet and / or outlet profiles ( 22 ) is provided. Heat exchanger according to claim 13, characterized in that at least those close to end walls ( 20 ) of the collecting tank ( 8th . 11 ) arranged first flow channels ( 5 ) with the inlet and / or outlet profiles ( 22 ) are provided.