TW202429036A - A heat exchanger plate, and a plate heat exchanger - Google Patents

Abstract

A heat exchanger plate (1) for a plate heat exchanger for heat exchange between at least a first fluid and a second fluid, the heat exchanger plate (1) having a quadrilateral shape with two opposite parallel primary sides (5) and two opposite parallel secondary sides (6), and a longitudinal central axis (x) being parallel with the primary sides (5). The heat exchanger plate (1) comprising a heat exchanging area having a corrugation of ridges and valleys having a longitudinal extension defining an inclination in relation to the longitudinal central axis (x), four portholes (11, 12, 13, 14), of which at least two are located at a respective corner of the heat exchanger plate (1) extending through the heat exchanger plate (1), a first set of ridges (8a) and valleys (9a) and a second set of ridges (8b) and valleys (9b), wherein the longitudinal extension of the first set of ridges and valleys (8a, 9a) define a first angle ([alpha]) in relation to a first primary side (5a) and the longitudinal extension of the second set of ridges and valleys (8b, 9b) define a second angle ([beta]) in relation to a second primary side (5b), wherein an intersection between the first set of ridges and valleys (8a, 9a) and the second set of ridges and valleys (8b, 9b) being defined as a transition area (10) comprising a curvature of ridges and valleys being concentric with a porthole.

Description

Heat exchanger plates and plate heat exchangers

The present invention relates to a heat exchanger plate as claimed in claim 1. The present invention also relates to a plate heat exchanger as claimed in claim 10.

A plate heat exchanger (PHE) typically consists of two end plates between which a number of heat transfer plates are arranged in a stack or package. The heat transfer plates of a PHE may be of the same or different types and they may be stacked in different ways. In some PHEs, the heat transfer plates are stacked with the front and rear sides of one heat transfer plate facing the front and rear sides of another heat transfer plate, respectively, and every other heat transfer plate is inverted relative to the remaining heat transfer plates. This is typically referred to as the heat transfer plates being "flipped" relative to each other. In other PHEs, the heat transfer plates are stacked with the front and rear sides of one heat transfer plate facing the rear and front sides, respectively. This is typically referred to as "rotating" the heat transfer plates relative to each other.

In certain types of plate heat exchangers, the heat carrier medium flowing around the closed channel area can be made to encounter high flow resistance when entering the heat exchanger area. This can be attributed to a relatively high theta pattern in the heat exchanger area, i.e. a corrugation pattern that can have a large inclination (herringbone angle) relative to the longitudinal center axis of the heat exchanger plate. A relatively high theta pattern generates more turbulence and therefore more heat transfer, higher pressure drop and higher flow resistance.

In other plate heat exchanger applications such as cooling electrical components, cooling needs to be done efficiently. Electrical components may be mounted in racks of data center servers where the components are arranged close to each other. When cooling electrical components, the fluid that comes into contact with the component must be carefully selected so as not to impair the efficiency of the component.

The object of the present invention is to overcome the problems discussed above. More precisely, the object of the present invention is to provide a heat exchanger plate and a plate heat exchanger that achieves low flow disturbances. A further object is to have a low pressure drop across the heat exchanger.

These objects are achieved by providing a heat exchanger plate having seamless integration of heat transfer areas and distribution areas and without abrupt changes in corrugation direction.

According to one aspect of the present invention, a heat exchanger plate for a plate heat exchanger is provided. The plate heat exchanger is used for heat exchange between at least a first fluid and a second fluid. The heat exchanger plate has a quadrilateral shape, the quadrilateral shape has two relatively parallel main sides and two relatively parallel secondary sides, and the longitudinal center axis is parallel to the main sides, wherein the heat exchanger plate includes: a heat exchange region having ridges and valleys, the ridges and valleys having a defined inclination relative to the longitudinal center axis a longitudinal extension of the heat exchanger plate; four channels, at least two of which are located at respective corners of the heat exchanger plate extending through the heat exchanger plate; a first set of ridges and valleys and a second set of ridges and valleys, wherein the longitudinal extension of the first set of ridges and valleys defines a first angle relative to the first main side, and the longitudinal extension of the second set of ridges and valleys defines a second angle relative to the second main side, wherein the intersection between the first set of ridges and valleys and the second set of ridges and valleys is defined as a transition region including the curvature of the ridges and valleys concentric with the channel.

Therefore, the concentric transition region between the corrugations having the first angle and the corrugations having the second angle achieves low flow disturbance.

Preferably, the ridges and valleys extend continuously from the first main side to the second main side. Thus, there is a smooth transition of the ripples from the first main side to the second main side, and vice versa.

Preferably, the first angle is greater than the second angle.

Preferably, the first angle is in the range of 50° to 70°. More specifically, the first angle may be 55°, 60° or 65°.

Preferably, the second angle is in the range of 30° to 60°. More specifically, the second angle can be 35°, 40°, 45°, 50° or 55°.

Preferably, the channel comprises a first channel, a second channel, a third channel and a fourth channel, and wherein the transition region is concentric with the first channel. This results in a radius with no abrupt changes in the direction of the corrugations over the entire plate, which results in good distribution of the fluid and low flow disturbances.

Preferably, the first and third holes have the same diameter, and wherein the second and fourth holes have the same diameter, and wherein the first and third holes have a larger diameter than the second and fourth holes.

Preferably, the distance between the two main sides is a maximum of 90 mm.

Preferably, the distance between the two main sides is a maximum of 45 mm.

According to a second aspect of the present invention, a plate heat exchanger is provided, comprising: a first heat exchanger plate and a second heat exchanger plate arranged side by side, a first plate gap for a first fluid, each first plate gap being formed by one of the first heat exchanger plates and an adjacent one of the second heat exchanger plates, and a second plate gap for a second fluid, each second plate gap being formed by one of the second heat exchanger plates and an adjacent one of the first heat exchanger plates, at least one of the first heat exchanger plates being a heat exchanger plate as in the first aspect.

Preferably, the first heat exchanger plate and the second heat exchanger plate are permanently joined to each other.

Preferably, the second heat exchanger plate is a mirrored version of the first heat exchanger plate.

Preferably, the first channel and the third channel are connected to the gap between the first plate, and the second channel and the fourth channel are connected to the gap between the second plate.

The plate heat exchanger can be constructed to operate as an evaporator or a condenser. However, the plate heat exchanger can also be used for other heat exchange applications. FIG. 3 discloses an embodiment of a plate heat exchanger, wherein a first heat exchanger plate A and a second heat exchanger plate B are arranged side by side in such a way that a first plate gap 3 for a first fluid and a second plate gap 4 for a second fluid are formed. At least one of the first heat exchanger plates A can be a heat exchanger plate 1 as described with respect to FIG. 1 .

In applications of the disclosed embodiments, the first fluid may be a heat carrier fluid, such as a dielectric fluid, and the second fluid may be water.

FIG1 discloses a heat exchanger plate 1 having a corrugation of ridges and valleys and having a quadrilateral shape with two opposite parallel main sides 5 and two opposite parallel secondary sides 6. In the disclosed embodiment, the quadrilateral shape is a rectangle with rounded corners, wherein the main sides 5 form the long sides and the secondary sides 6 form the short sides. The plate comprises a first main side 5a and a second main side 5b. The heat exchanger plate comprises a heat exchanger area extending parallel to the extension plane.

The longitudinal center axis x extends through the secondary side 6 and is parallel to the primary side 5. The longitudinal center axis x is parallel to the extension plane of each of the first heat exchanger plate A and the second heat exchanger plate B ( FIG. 3 ).

The heat exchanger plate 1 has a first channel 11, a second channel 12, a third channel 13 and a fourth channel 14. Two of the four channels are located close to the secondary side, and the other two channels are located close to the opposite secondary side. The second channel 12 is located closer to the corner of the plate than the first channel 11. The fourth channel 14 is located closer to the corner of the plate than the third channel 13.

In the packaging of the heat exchanger plate, the channels can be grouped into 11 and 12, which are used as inlet channels for the first fluid and the second fluid, respectively. Channels 13 and 14 are then used as outlet channels for the first fluid and the second fluid, respectively. The first channel 11 is the inlet of the first fluid and the third channel 13 is the outlet of the first fluid, wherein these two channels have the same diameter. The second channel 12 is the inlet of the second fluid and the fourth channel 14 is the outlet of the second fluid, wherein these two channels have the same diameter and their diameter is smaller than the channel for the first fluid. The first channel 11 and the third channel 13 are arranged in the recessed hot plate area. The first and second fluids may also be directed through the heat exchanger plate package in opposite directions such that the first channel 11 is the outlet of the first fluid and the third channel 13 is the inlet of the first fluid, and the second channel 12 is the outlet of the second fluid and the fourth channel 14 is the inlet of the second fluid.

The heat exchanger plate 1 has a rather elongated configuration, wherein the length of the primary side 5 is more than four times the length of the secondary side 6.

FIG. 2A discloses a heat exchanger plate 1 having a corrugation of ridges 8a, 8b and valleys 9a, 9b near the first inlet channel 11 and the second inlet channel 12. The ridges and valleys have a constant width along their extension from a first main side 5a to the second main side 5b. The first set of ridges 8a and the first set of valleys 9a are located close to the first main side 5a, and the second set of ridges 8b and the second set of valleys 9b are located close to the second main side 5b. The first inlet channel 11 is closer to the first main side 5a, and the second inlet channel 12 is closer to the second main side 5b.

The ridges 8a, 8b and the valleys 9a, 9b have an inclination relative to the main sides 5a, 5b, respectively (the main sides are parallel to the longitudinal center axis x). The first group of ridges 8a and valleys 9a are inclined at a first angle α relative to the first main side 5a. The second group of ridges 8b and valleys 9b are inclined at a second angle β relative to the second main side 5b. The first angle α is greater than the second angle β. The first angle α is in the range of 50° to 70°, or a value in between the range, such as 55°, 60° or 65°. The second angle β is in the range of 30° to 60°, or a value in between the range, such as 35°, 40°, 45°, 50° or 55°.

The transition region 10 is defined where the first set of ridges 8a and valleys 9a intersects with the second set of ridges 8b and valleys 9b. The curvature of the ridges and valleys in the transition region 10 is concentric with the first channel 11.

The corrugations of ridges 8a, 8b and valleys 9a, 9b extend between a top plane and a bottom plane. The top plane and the bottom plane are parallel to each other and to the extension plane. The ridges extend along the top plane, and the valleys extend along the bottom plane.

Fig. 2B discloses a cross-section taken along line AA' in Fig. 2A and depicts the top plane of the first set of ridges 8a and the bottom plane of the first set of valleys 9a. The second set of ridges 8b and valleys 9b have corresponding cross-sectional profiles.

FIG. 2C illustrates a cross-section taken along line BB′ in FIG. 2A , wherein the first channel 11 and the second channel 12 are disclosed as being located in different planes.

3 discloses a plate heat exchanger comprising a plurality of first heat exchanger plates A and a plurality of second heat exchanger plates B arranged in alternating order in parallel with each other in the plate heat exchanger. The side view is taken as a cross section through the center of the second channel 12 and the fourth channel 14, wherein the cut is parallel to the longitudinal center axis x.

3 , each of the first plate interspaces 3 is formed by one of the first heat exchanger plates A and an adjacent one of the second heat exchanger plates B. Each of the second plate interspaces 4 is formed by one of the second heat exchanger plates B and an adjacent one of the first heat exchanger plates A.

The first plate gap 3 and the second plate gap 4 are arranged in parallel with each other in an alternating order. The first inlet channel connected to the first inlet channel and the first outlet channel connected to the first outlet channel are communicated with the first plate gap 3 so as to supply the first fluid to the first plate gap 3 and discharge the first fluid from the first plate gap 3. The second inlet channel connected to the first inlet channel and the second outlet channel connected to the second outlet channel are communicated with the second plate gap 4 so as to supply the second fluid to the second plate gap 4 and discharge the second fluid from the second plate gap 4.

In the disclosed embodiment, the first heat exchanger plate A and the second heat exchanger plate B are permanently joined to each other, preferably brazed to each other. However, the first heat exchanger plate A and the second heat exchanger plate B can be mounted together in other ways, such as by means of tension bolts.

A flange of an edge region of one of the first heat exchanger plates A may be joined to a corresponding flange of an edge region of a neighboring one of the second heat exchanger plates B.

As mentioned above, the disclosed embodiment refers to an evaporator. According to another embodiment, the heat exchanger plates and plate heat exchangers can be used as condensers.

The embodiments disclosed and discussed above are configured for countercurrent flow of a first fluid and a second fluid. However, embodiments may alternatively be configured for cocurrent flow of a first fluid and a second fluid, wherein, for example, the first outlet channel forms an inlet for the first fluid, and the first inlet channel forms an outlet for the first fluid.

The present invention is not limited to the disclosed embodiments but may be modified and varied within the scope of the following claims.

without

The present invention is now explained in more detail by describing various embodiments and with reference to the drawings attached hereto. [FIG. 1] schematically discloses a top view of a heat exchanger plate according to an embodiment of the present invention. [FIG. 2A] schematically discloses an enlarged view of FIG. 1. [FIG. 2B] discloses a cross section along line AA' in FIG. 2A. [FIG. 2C] discloses a cross section along line BB' in FIG. 2A. [FIG. 3] schematically discloses a side view of a plate heat exchanger having at least one plate of the embodiment of FIG. 1.

Claims (13)

A heat exchanger plate (1) for a plate heat exchanger, the plate heat exchanger being used for heat exchange between at least a first fluid and a second fluid, the heat exchanger plate (1) having a quadrilateral shape, the quadrilateral shape having two oppositely parallel main sides (5) and two oppositely parallel secondary sides (6), and a longitudinal center axis (x) parallel to the main sides (5), the heat exchanger plate (1) comprising a heat exchange region having a corrugation of ridges and valleys, the ridges and valleys having a longitudinal extension defining an inclination relative to the longitudinal center axis (x), Four channels (11, 12, 13, 14), at least two of which are located at a respective corner of the heat exchanger plate (1) extending through the heat exchanger plate (1), characterized by a first set of ridges (8a) and valleys (9a) and a second set of ridges (8b) and valleys (9b), wherein the longitudinal extension of the first set of ridges and valleys (8a, 9a) defines a first angle (α) relative to a first main side (5a), and the longitudinal extension of the second set of ridges and valleys (8b, 9b) defines a second angle (β) relative to a second main side (5b), wherein an intersection between the first set of ridges and valleys (8a, 9a) and the second set of ridges and valleys (8b, 9b) is defined as a transition region (10) of curvature comprising ridges and valleys concentric with a channel. A heat exchanger plate as claimed in claim 1, wherein the ridges (8a, 8b) and valleys (9a, 9b) extend continuously from the first main side (5a) to the second main side (5b). A heat exchanger plate as in any one of claims 1 or 2, wherein the first angle (α) is greater than the second angle (β). A heat exchanger plate as claimed in any one of claims 1 to 3, wherein the first angle (α) is in the range of 50° to 70°. A heat exchanger plate as claimed in any one of claims 1 to 4, wherein the second angle (β) is in the range of 30° to 60°. A heat exchanger plate as claimed in any one of claims 1 to 5, wherein the channels include a first channel (11), a second channel (12), a third channel (13) and a fourth channel (14), and wherein the transition region (10) is concentric with the first channel (11). A heat exchanger plate as claimed in claim 6, wherein the first channel (11) and the third channel (13) have the same diameter, and wherein the second channel (12) and the fourth channel (14) have the same diameter, and wherein the first channel and the third channel (11, 13) have a larger diameter than the second channel and the fourth channel (12, 14). A heat exchanger plate as claimed in any one of claims 1 to 7, wherein the distance between the two main sides (6) is at most 90 mm. A heat exchanger plate as claimed in any one of claims 1 to 8, wherein the distance between the two main sides (6) is at most 45 mm. A plate heat exchanger comprising a first heat exchanger plate (A) and a second heat exchanger plate (B) arranged side by side, a first plate gap (3) for a first fluid, each first plate gap (3) being formed by one of the first heat exchanger plates (A) and an adjacent one of the second heat exchanger plates (B), and a second plate gap (4) for a second fluid, each second plate gap (4) being formed by one of the second heat exchanger plates (B) and an adjacent one of the first heat exchanger plates (A), wherein at least one of the first heat exchanger plates (A) is a heat exchanger plate (1) as claimed in any one of claims 1 to 9. A plate heat exchanger as claimed in claim 10, wherein the first heat exchanger plate and the second heat exchanger plate (A, B) are permanently joined to each other. A plate heat exchanger as in any one of claims 10 or 11, wherein the second heat exchanger plates (B) are mirrored versions of the first heat exchanger plates (A). A plate heat exchanger as claimed in claim 11, wherein the first channel (11) and the third channel (13) are connected to the first plate gaps (3), and wherein the second channel (12) and the fourth channel (14) are connected to the second plate gaps (4).