PLATE HEAT EXCHANGER, PROCESS ENGINEERING SYSTEM AND METHOD
20210231382 · 2021-07-29
Inventors
- Manfred Steinbauer (Raisting, DE)
- Rainer Flüggen (Bichl, DE)
- Axel LEHMACHER (Egling-Moosham, DE)
- Clemens Baumgartner (Geretsried, DE)
- Konrad BRAUN (Lenggries, DE)
- Rainer Hoffmann (Unterhaching, DE)
- Alexander WOITALKA (München, DE)
- Stefan GEWALD (Neuried, DE)
- Janine Blank (Kienberg, DE)
- Christiane Kerber (Pöcking, DE)
Cpc classification
F28F27/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F28F2200/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
G01K11/32
PHYSICS
F28F3/12
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
G01K1/14
PHYSICS
International classification
F28D9/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
The invention relates to a plate heat exchanger (1) for a process engineering system (2), having a plurality of lamellae (3, 4) and a plurality of separating plates (5-7), which are arranged alternately, wherein at least one separating plate (6) has an optical waveguide (35) that is embedded in the at least one separating plate (6) in such a way that the optical waveguide (35) is covered on both sides by material of the at least one separating plate (6) in a first direction (R1) and in a second direction (R2), which are each oriented perpendicular to a plane (E) defined by the at least one separating plate (6) and in opposite senses with respect to one another.
Claims
1. Plate heat exchanger (1) for a process engineering system (2), having a plurality of lamellae (3, 4) and a plurality of separating plates (5-7), which are arranged alternately, wherein at least one separating plate (6) has an optical waveguide (35) that is embedded in the at least one separating plate (6) in such a way that the optical waveguide (35) is covered on both sides by material of the at least one separating plate (6) in a first direction (R1) and in a second direction (R2), which are each oriented perpendicular to a plane (E) defined by the at least one separating plate (6) and in opposite senses with respect to one another.
2. Plate heat exchanger according to claim 1, comprising a first lamella (3) and a second lamella (4), wherein the at least one separating plate (6) is arranged between the first lamella (3) and the second lamella (4), and wherein the optical waveguide (35) is embedded in the at least one separating plate (6) in such a way that the optical waveguide (35) is covered by the material of the at least one separating plate (6) both in the direction (R1) of the first lamella (3) and in the direction (R2) of the second lamella (4).
3. Plate heat exchanger according to claim 1, wherein the at least one separating plate (6) has a first separating plate portion (36) and a second separating plate portion (37), between which the optical waveguide (35) is arranged.
4. Plate heat exchanger according to claim 3, wherein the first separating plate portion (36) and the second separating plate portion (37) are bonded to each other by means of a solder (43).
5. Plate heat exchanger according to claim 4, wherein the optical waveguide (35) is embedded in the solder (43).
6. Plate heat exchanger according to claim 3, wherein the first separating plate portion (36) and/or the second separating plate portion (37) have a groove (38) in which the optical waveguide (35) is arranged.
7. Plate heat exchanger according to claim 1, wherein the optical waveguide (35) is completely surrounded by the material of the at least one separating plate (6).
8. Plate heat exchanger according to claim 7, wherein the at least one separating plate (6) is formed in one piece.
9. Plate heat exchanger according to claim 1, wherein the optical waveguide (35) is received in a sleeve (44).
10. Process engineering system (2) having a plate heat exchanger (1) according to claim 1.
11. Method for producing a plate heat exchanger (1) for a process engineering system (2), having the following steps: a) providing (S1) a plurality of lamellae (3, 4), b) providing (S2) a plurality of separating plates (5-7), c) providing (S3) an optical waveguide (35), d) embedding (S4) the optical waveguide (35) in at least one separating plate (6) in such a way that the optical waveguide (35) is covered on both sides by material of the at least one separating plate (6) in a first direction (R1) and in a second direction (R2), which are each oriented perpendicular to a plane (E) defined by the at least one separating plate (6) and in opposite senses with respect to one another, and e) alternately arranging (S5) the lamellae (3, 4) and the separating plates (5-7).
12. Method according to claim 11, wherein, in step d), the optical waveguide (35) is arranged between a first separating plate portion (36) and a second separating plate portion (37) of the at least one separating plate (6).
13. Method according to claim 12, wherein, in step d), the first separating plate portion (36) and the second separating plate portion (37) are bonded to each other by means of a solder (43).
14. Method according to claim 13, wherein, in step d), the optical waveguide (35) or a sleeve (44) in which the optical waveguide (35) can be received is embedded in the solder (43) and/or is arranged in a groove (38) having the first separating plate portion (36) and/or the second separating plate portion (37).
15. Method according to claim 11, wherein, in step d), the at least one separating plate (6) is constructed around the optical waveguide (35) with the aid of a generative manufacturing method.
Description
[0041] Further advantageous embodiments and aspects of the plate heat exchanger, of the process engineering system, and/or of the method are the subject matter of the subclaims and of the exemplary embodiments of the plate heat exchanger, the process engineering system, and/or the method described below. Furthermore, the plate heat exchanger, the process engineering system, and/or the method are explained in more detail with reference to the enclosed figures on the basis of preferred embodiments.
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[0050]
[0051]
[0052] In the figures, the same or functionally equivalent elements have been provided with the same reference symbols unless otherwise stated.
[0053]
[0054] The plate heat exchanger 1 is, in particular, a plate fin heat exchanger (PFHE) or can be referred to as such. The plate heat exchanger 1 can be part of a process engineering system 2. The process engineering system 2 can, for example, be a system for air separation or for the production of liquefied natural gas (LNG), a system used in the petrochemical industry, or the like.
[0055] The process engineering system 2 can comprise a plurality of such plate heat exchangers 1.
[0056] The plate heat exchanger 1 is of parallelepipedal or block-shaped construction and comprises a plurality of lamellae 3, 4 (
[0057] The separating plates 5 through 7 can be manufactured from, for example, aluminum or steel—in particular, from stainless steel. The number of lamellae 3, 4 and separating plates 5 through 7 is arbitrary.
[0058] The plate heat exchanger 1 further comprises cover plates 8, 9, between which the plurality of fins 3, 4 and the plurality of separating plates 5 through 7 are arranged. The cover plates 8, 9 can be constructed identically to the separating plates 5 through 7. Furthermore, the plate heat exchanger 1 comprises so-called sidebars or edge strips 10, 11 which laterally delimit the lamellae 3, 4. The edge strips 10, 11 can be bonded, e.g., soldered or welded, to the separating plates 5 through 7 and/or the lamellae 3, 4. In the case of bonded connections, the connection partners are held together by atomic or molecular forces. Bonded connections are non-releasable connections which can be separated only by destroying the connecting means.
[0059] With the aid of the lamellae 3, 4 and the separating plates 5 through 7, the plate heat exchanger 1 forms a plurality of parallel heat transfer passages, in which process media can flow and can indirectly transfer heat to process media guided in adjacent heat transfer passages. The individual heat transfer passages can in each case be charged with a stream of a process medium by means of nozzles 12 through 18 and so-called headers 19 through 28. The headers 19 through 28 may be referred to as manifolds or are manifolds.
[0060] As
[0061] Each separating plate 5 through 7 defines a plane E. In
[0062] As
[0063] The corrugated geometry of the lamellae 3, 4 is formed in that each lamella 3, 4 has a plurality of legs 30, 31 which are arranged parallel to one another and extend, in particular, perpendicular to the separating plates 5 through 7. Furthermore, the lamellae 3, 4 each comprise second legs 32, 33 which are positioned parallel to one another and which connect the first legs 30, 31 in the orientation of
[0064] A plate heat exchanger 1 as previously explained may be sensitive to thermal stresses. These thermal stresses can be caused by different temperatures of the process media which are in heat exchange. Thermal stresses can lead to mechanical damage to the plate heat exchanger 1 and, in particular, to leakage between the individual heat transfer passages up to leakage with respect to an environment of the plate heat exchanger 1. For this reason, a measuring device 34 is provided, which is set up to measure or detect a time curve of the temperature distribution and/or a strain distribution within the plate heat exchanger 1—in particular, in a spatially-resolved manner.
[0065] The measuring device 34 here comprises an optical waveguide 35 (
[0066] As
[0067] The separating plate 6 may include a first separating plate portion 36 and a second separating plate portion 37. The optical waveguide 35 is arranged between the first separating plate portion 36 and the second separating plate portion 37. The separating plate portions 36, 37 are formed in sheet-like fashion. For example, the separating plate 6 thus has a thickness d6 of approximately 1.4 mm. The optical waveguide 35 itself may have a diameter d35 of about 125 μm. The first separating plate portion 36 has a thickness d36, and the second separating plate portion 37 has a thickness d37. The thicknesses d36, d37 may be the same or different. For example, the thickness d36 is greater than the thickness d37. The plane E preferably runs centrally through the separating plate 6.
[0068] A groove 38 in which the optical waveguide 35 is received is provided in the first separating plate portion 36 and/or in the second separating plate portion 37. The groove 38 may be rectangular in cross-section, as shown in
[0069] The separating plate 6 comprises an x-direction or width direction x, a y-direction or depth direction y oriented perpendicular to the width direction x, and a z-direction or thickness direction z oriented both perpendicular to the width direction x and perpendicular to the depth direction y. The directions x, y, z form a coordinate system of the separating plate 6. The thicknesses d6, d36, d37 and the depth t38 are measured in the thickness direction z. The thickness direction z can coincide with the second direction R2. The side edges 39, 41 run in the width direction x, and the side edges 40, 42 run in the depth direction y. The plane E is defined, in particular, by the width direction x and the depth direction y of the separating plate 6. The thickness direction z, like the directions R1, R2, is oriented perpendicular to the plane E.
[0070] The first separating plate portion 36 and the second separating plate portion 37 are bonded to each other by a solder 43. The solder 43 is provided areally between the first separating plate portion 36 and the second separating plate portion 37. The solder 43 may also fill a cavity formed by the groove 38 between the separating plate portions 36, 37. The optical waveguide 35 can also have a sleeve 44 in which the optical waveguide 35 is accommodated. The optical waveguide 35 is slidably received in the sleeve 44. The sleeve 44 may be made of a metal, for example.
[0071] The optical waveguide 35 is now embedded in the separating plate 6 in such a way that the optical waveguide 35, viewed in both directions R1, R2, is covered on two sides or on both sides by material of the separating plate 6.
[0072] That is, in the orientation of
[0073] The measuring device 34 is now suitable for detecting or measuring a temperature distribution and/or a strain distribution in the separating plate 6—in particular, in a spatially-resolved manner—with the aid of the embedded optical waveguide 35. For example, the temperature measurement can take place via the evaluation of optical signals such as are produced by Raman scattering. An optical waveguide 35 as explained above is generally made of doped quartz glass (amorphous solid-state structure of mainly silicon dioxide). In such amorphous solid-state structures, lattice vibrations are induced by thermal effects. Such lattice vibrations are temperature-dependent. Light incident on the molecules or particles in the optical waveguide 35 interacts with the electrons of the molecules. These interactions are called Raman scattering. The backscattered light can be divided into three spectral groups.
[0074] In addition to Rayleigh scattering, which has the same wavelength as the introduced light, what are known as Stokes and anti-Stokes components exist. In contrast to the Stokes components, which are shifted to higher wavelengths and are temperature-independent, the anti-Stokes components, which are shifted to smaller wavelengths, are temperature-dependent. An intensity ratio between Stokes and anti-Stokes components can thus be used for temperature measurement. The intensity of the two components is obtained over the length of the optical waveguide 35 via a Fourier transformation of these two, backscattered components, in comparison with a Fourier transformation of a reference signal. The temperature for each point of the optical waveguide 35 can thus be determined by comparing the two intensities.
[0075] Alternatively, the temperature measurement can take place via the evaluation of optical signals such as are produced by Brillouin scattering of the optical waveguide 35. In this case, the temperature measurement is based upon the spatially-resolved determination of a difference frequency between a primary light wave coupled into the optical waveguide 35 and the wave induced and backscattered in the optical waveguide 35 as a result of Brillouin scattering, the frequency of which wave is reduced relative to the primary wave as a function of the temperature. With a pulsed, irradiated, primary light wave, the frequency shift can, due to the temperature change, be determined in a spatially-resolved manner by time-resolved detection of the signal light for different frequency differences and knowledge of the pulse propagation time. In this case also, the temperature at any point of the optical waveguide 35 can thus also be determined by analyzing the optical signals.
[0076] Furthermore, the temperature measurement can take place via the evaluation of optical signals, such as are produced by scattering on a Bragg grating. Bragg gratings are optical band filters which are written into the optical waveguide 35 and can be placed in the optical waveguide 35 more or less as frequently as desired. A center wave number of the band stop results from the so-called Bragg condition. The spectral width of the band stop depends not only upon the grating length and the refractive index, but also upon the temperature. Thus, for a given grating length and refractive index that vary over the optical waveguide 35, one can determine the temperature at the respective location of the Bragg grating over the width of the band stop.
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[0078] A supporting structure or a spacer 45 can be provided between the first separating plate portion 36 and the second separating plate portion 37, which prevents damage to the optical waveguide 35 during the assembly of the separating plate 6. The spacer 45 has a thickness d45 which is larger than the diameter d35 (
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[0080] In this embodiment of the separating plate 6, the optical waveguide 35 is completely surrounded by material of the separating plate 6. The separating plate 6 is formed integrally—in particular, in one piece. For this purpose, the separating plate 6 is produced by means of an additive or generative production method. For example, a powder-based generative manufacturing method—in particular, a 3-D printing method—can be used. For this purpose, the separating plate 6 is constructed from a pulverulent material. This pulverulent material can, for example, be melted in layers with the aid of a laser beam in order to form the separating plate 6. For example, selective laser melting (SLM), selective laser sintering (SLS) or the like may be used as the generative manufacturing method. The fact that the separating plate 6 is produced by means of a generative manufacturing method can be demonstrated microscopically by a layered or layer-by-layer construction of the separating plate 6.
[0081] A channel 46 in which the optical waveguide 35 is received is formed in the separating plate 6. The optical waveguide 35 can in turn, as mentioned above, be accommodated in a sleeve 44. The separating plate 6 can be produced, for example, in such a way that the production method for producing the separating plate 6 is carried out in such a way that a lower—in the orientation of
[0082] With the aid of the aforementioned separating plate 6, a high-resolution and exact measurement of the temperature and/or the elongation on or in the separating plate 6 itself can take place. No additional, or only a little additional, installation space is required. There may be no undesirable influence on the measured temperature due to environmental influences, since the separating plate 6 is positioned inside the plate heat exchanger 1. Both expansion and temperature measurement are possible. Different fiber types for the optical waveguide 35 can be selected for this purpose. Several—in particular, different—optical waveguides 35 can also be provided in the separating plate 6. With the aid of the separating plate 6, an increase in the component reliability against failure or against leakages to the inside and to the outside can thus be achieved. The availability of the separating plate 6 is increased. Channels (not shown) provided in the separating plate 6 can also serve to remove material samples, provided that they are connected to the corresponding heat transfer passage.
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[0084] In a step S3, at least one optical waveguide 35 is provided. In a further step S4, the optical waveguide 35 is embedded in at least one of the separating plates 5 through 7 viz., for example, in the separating plate 6, such that the optical waveguide 35, as viewed in the first direction R1 and in the second direction R2, is covered on two sides or on both sides by material of the at least one separating plate 6. The lamellae 3, 4 and the separating plates 5 through 7 can then be arranged alternately in a step S5 in order to form the plate heat exchanger 1. In this case, the lamellae 3, 4 and the separating plates 5 through 7 can be soldered or welded together.
[0085] The embedding of the optical waveguide 35 can be effected by arranging the optical waveguide 35 between the first separating plate portion 36 and the second separating plate portion 37. The two separating plate portions 36, 37 can be connected to one another in a bonded manner by means of the solder 43. In the process, the optical waveguide 35 can either be embedded in the solder 43, or the optical waveguide is inserted into the groove 38 provided on at least one of the separating plate portions 36, 37 before soldering or welding the two separating plate portions 36, 37. Alternatively, the separating plate 6 can also be constructed around the optical waveguide 35 with the aid of a generative manufacturing method.
[0086] Although the present invention has been described with reference to exemplary embodiments, it can be modified in many ways.
REFERENCE SYMBOLS USED
[0087] 1 Plate heat exchanger [0088] 2 Process engineering system [0089] 3 Lamella [0090] 4 Lamella [0091] 5 Separating plate [0092] 6 Separating plate [0093] 7 Separating plate [0094] 8 Cover plate [0095] 9 Cover plate [0096] 10 Edge strip [0097] 11 Edge strip [0098] 12 Nozzle [0099] 13 Nozzle [0100] 14 Nozzle [0101] 15 Nozzle [0102] 16 Nozzle [0103] 17 Nozzle [0104] 18 Nozzle [0105] 19 Header [0106] 20 Header [0107] 21 Header [0108] 22 Header [0109] 23 Header [0110] 24 Header [0111] 25 Header [0112] 26 Header [0113] 27 Header [0114] 28 Header [0115] 29 Channel [0116] 30 Leg [0117] 31 Leg [0118] 32 Leg [0119] 33 Leg [0120] 34 Measuring device [0121] 35 Optical waveguide [0122] 36 Separating plate portion [0123] 37 Separating plate portion [0124] 38 Groove [0125] 39 Side edge [0126] 40 Side edge [0127] 41 Side edge [0128] 42 Side edge [0129] 43 Solder [0130] 44 Sleeve [0131] 45 Spacer [0132] 46 Channel [0133] 47 Separating line [0134] d6 Thickness [0135] d35 Diameter [0136] d36 Thickness [0137] d37 Thickness [0138] d43 Thickness [0139] d45 Thickness [0140] E Plane [0141] R1 Direction [0142] R2 Direction [0143] S1 Step [0144] S2 Step [0145] S3 Step [0146] S4 Step [0147] S5 Step [0148] t38 Depth [0149] x width direction [0150] y depth direction [0151] z thickness direction