KR20060061472A - Plate having 3-dimensional microchannel and heat exchanger using it - Google Patents

Abstract

According to the present invention, a fluid inlet and a fluid outlet part are formed in a heat exchanger and partially communicated with inlets and outlets formed at diagonal corners, and are formed between the fluid inlet part and the fluid outlet part to draw fluid introduced from the inlet part. A plate having microchannels for flowing from a fluid inlet to a outlet through a fluid outlet, the microchannel comprising: a plurality of front concave grooves arranged at predetermined intervals on the front face of the plate; A plurality of rear surface concave grooves arranged on the rear surface of the plate at predetermined intervals, the rear surface concave grooves being formed in a direction that is displaced from a direction in which the front concave grooves are formed; The plate is formed through the bottom portion of the front concave grooves and the bottom of the rear concave grooves formed in a direction that is displaced from the front concave grooves so that the fluid flowing through the front concave groove and the rear concave groove. It characterized in that it comprises a plurality of mixing spaces for allowing the fluid flowing through the mixing, and provides a plate for generating a vortex which is a secondary flow different from the main flow direction in the mixing space, the plate adjacent by the secondary flow It provides a heat exchanger that can increase the heat exchange efficiency in between.

Heat exchanger, plate, three-dimensional microchannels, MEMS

Description

Plate having 3-dimensional microchannel and heat exchanger using it

1 shows a plate with conventional microchannels;

2 is a view showing a heat exchange state of a conventional heat exchanger using the plate of FIG.

3 shows an embodiment of a plate on which a three-dimensional microchannel is formed in accordance with the present invention;

4 is an enlarged perspective view showing one of the microchannels of FIG. 3 in an enlarged manner;

5 shows yet another embodiment of a plate on which a three-dimensional microchannel is formed according to the invention;

6 is an enlarged perspective view illustrating an enlarged portion of the microchannel of FIG. 5;

7 (a), 7 (b) and 7 (c) show another embodiment of a pattern of microchannels according to the present invention; And

8 is a view showing the structure of a heat exchanger using a plate on which three-dimensional microchannels are formed according to the present invention.

<Explanation of symbols for the main parts of the drawings>

20 plate 21 through hole

22: fluid inlet 23: fluid outlet

30: three-dimensional microchannel 31: front concave groove

32: rear concave groove 33: mixing space

40: diaphragm

The present invention relates to a plate having a microchannel and constituting a heat exchanger, and a heat exchanger using the same. More specifically, a plate having a three-dimensional microchannel which forms a three-dimensional microchannel capable of more actively mixing flow, and has improved heat exchange performance by a secondary flow such as a vortex generated by the flow mixing, and the same. It relates to a heat exchanger used.

Microchannels used in heat exchangers are channels whose characteristic length is less than 1 mm and larger than 1 μm. Heat exchangers with microchannels, one of the MEMS (Micro Elector-Mechanical System) technologies, make narrow microchannels by making the heat transfer coefficients inversely proportional to the diameter of the tubes in steady-state tube flow, It is used for the cooling of small devices by flowing heat exchanged fluid with high temperature and low temperature.

The recent miniaturization of mechanical and electronic equipment has resulted in a significant increase in the amount of heat generated per unit area, which has led to the problem of system instability and shutdown due to exceeding the limit of the cooling system that cools the system for stable operation. have.

In order to solve this problem, studies on a small heat exchanger having a micro channel have been actively conducted. At present, a plate having a micro channel as shown in FIGS. 1 and 2 and a small device using the same are cooled. Heat exchanger is used. Such heat exchangers are used not only for electronic equipment, but also for chemical processes that require reaching a target temperature in a short time, and are particularly actively used in reformers of fuel cells, which are devices that separate hydrogen from fuel.

As shown in FIG. 2, the heat exchanger has a plate 10: 10a and 10b having the microchannels 11: 11a and 11b stacked therein, and is placed in front of or behind the plate 10a through which a high temperature fluid flows. It has a structure which arrange | positions the plate 10b through which the low temperature fluid flows, or the plate through which the high temperature fluid flows in front of or behind the plate through which the low temperature fluid flows. Specifically, as shown in FIG. 1, each plate 10 has a quadrangular shape as a whole, and has a fluid receiving part 12 which is concave to allow fluid to flow in a diagonal direction on one side thereof. . In the central portion of the fluid receiving portion 12, a plurality of microchannels 11 having a linear form are arranged.

In addition, the inlet 13 and the outlet 14 are formed in the diagonal direction of the plate 10 and the fluid receiving portion 12 is formed up to the position of the inlet 13 and the outlet 14. The fluid flows through the inlet 13 and the outlet 14 as shown in FIG. 1 and flows through the inlet 13 into the left space of the fluid receiving portion 12 and is formed at the center of the fluid receiving portion 12. It flows through the micro channel 11 to the right side of the fluid receiving portion 12 and flows out through the outlet 14. Since the hole 15 formed at a position symmetrical with the inlet 13 and the outlet 14 formed in the plate 10 in FIG. 1 is not connected to the fluid receiving portion 12, the neighboring region as shown in FIG. 2 is shown. It only serves to pass the fluid through the plate, the fluid does not flow to the fluid receiving portion (12). In addition, the microchannel 11 has a structure in which a plurality of concave grooves 110 are arranged at predetermined intervals as described in the enlarged view of FIG. 1, and fluid passes through the concave grooves 110. .

Several plates 10 are stacked to form a heat exchanger, and as shown in FIG. 2, the plate 10a includes a fluid receiving portion 12a and a micro channel 11a formed so that fluid flows from left to right. The plate 10b is provided with the fluid accommodating part 12b formed so that fluid may flow from right to left. In the plate 10a, the hot fluid flowing through the inlet 12a flows through the microchannel 11a to the outlet 13a. Likewise, in the plate 10b, the low temperature fluid entering the inlet 13b flows into the microspheres. It flows through the channel 11b to the outlet 14b. Since the plates 10a and 10b are stacked, the high-temperature fluids and the low-temperature fluids exchange heat with each other while moving the microchannels 11a and 11b.

Since the microchannel 11 formed in the plate 10 of the micro heat exchanger described above has a straight pipe shape, the distance between the high temperature fluid and the low temperature fluid is also in micro units, so the conduction thermal resistance is low, indicating high heat transfer performance. . However, the flow through the micro-channel 11 also has a characteristic length in micro units, so even when the velocity of the fluid passing through the micro-channel 11 is large, the form of the flow becomes a laminar flow and a fluid having a direction perpendicular to the flow direction. Since there is no secondary flow, there is a problem that the effect of heat transfer due to convection cannot be achieved.

The present invention is to solve the problems occurring in the plate of the conventional micro heat exchanger, having a mixing space that can be mixed with the flow and the three-dimensional micro-channel for generating a secondary flow vortex when the fluid flows along the channel An object of the present invention is to provide a plate having a higher heat transfer performance by flow mixing in a channel and a heat exchanger using the same.

In order to achieve the above object, the present invention is formed laminated on the heat exchanger, having a fluid inlet and a fluid outlet part in communication with the inlet and the outlet formed in the diagonal corner formed between the fluid inlet and the fluid outlet A plate having microchannels for flowing fluid flowing from the inlet to the outlet through the fluid outlet, the microchannel comprising: a plurality of fronts arranged at predetermined intervals on the front face of the plate; Concave grooves; A plurality of rear surface concave grooves arranged on the rear surface of the plate at predetermined intervals, the rear surface concave grooves being formed in a direction that is displaced from a direction in which the front concave grooves are formed; The plate penetrates at a portion where the bottoms of the front concave grooves and the bottoms of the rear concave grooves are formed so as to deviate from the front concave grooves, so that the fluid flowing through the front concave groove and the rear concave groove are formed. By having a plurality of mixing spaces to mix the fluid flowing through the flow, the fluid flowing along the front concave groove and the rear concave groove is combined in the mixing space to generate a secondary flow different from the main flow direction.

In addition, in the present invention, the concave grooves formed on at least one of the front and rear concave grooves formed on the front and rear surfaces of the plate to form the micro channel are arranged at regular intervals It is easy to manufacture by having a regular pattern formed.

Further, in the present invention, the front concave grooves and the rear concave grooves are formed to have the same pattern, and when viewed from the front, the front concave grooves and the rear concave grooves are mirror-symmetrical with each other and the front concave. The use of the same pattern in the fabrication of the grooves and the back concave grooves facilitates the fabrication.

In addition, in the present invention, the pattern may be a straight line inclined so that the recessed grooves have a predetermined slope.

Further, in the present invention, the pattern may have a shape in which the concave grooves are linearly inclined and the inclined portion having the inclined repeatedly.

In addition, in the present invention, the pattern may be a shape in which the concave grooves entirely form a V-shape.

In addition, in the present invention, the front concave grooves and the rear concave grooves of the micro channel may be formed using an etching method to realize a more accurate and regular shape of the concave groove.

In another aspect, the present invention is laminated to a plurality of plates formed with the three-dimensional micro-channel, such that the inlet and outlet are located in opposite directions to each other; A diaphragm between the plates to prevent fluid from flowing between the plate and the plate; The diaphragm may be applied to a heat exchanger having through holes formed at four corners, thereby increasing heat exchange efficiency between the plate and the plate due to the secondary flow generated in the mixing space of the three-dimensional microchannel.

DETAILED DESCRIPTION Hereinafter, embodiments according to the present invention will be described with reference to the accompanying drawings. 3 is a view showing an embodiment of a plate on which a three-dimensional microchannel according to the present invention is formed, FIG. 4 is an enlarged perspective view showing one of the microchannels of FIG. 3 in an enlarged view, and FIG. FIG. 6 is a view illustrating another example of a plate on which a dimensional microchannel is formed, and FIG. 6 is an enlarged perspective view showing a part of the microchannel of FIG. 5 in an enlarged manner, and FIGS. 8 is a view showing another embodiment of the pattern of the microchannel according to the present invention, Figure 8 is a view showing the structure of a heat exchanger using a plate with a three-dimensional microchannel according to the present invention.

According to FIG. 3, the plate 20 on which the three-dimensional microchannel 30 is formed according to the present invention has a quadrangular shape as in the related art, and through holes 21 are formed at four corners, and are arranged diagonally. The pair becomes the inlet 210 and the outlet 211 through which the fluid flows into the plate 20, and the other pair of through holes 212 serves as a passage through which the fluid flows to the neighboring plate.

The fluid inlet part 22 and the fluid outlet part 23 which communicate with a part of the inlet 210 and the outlet 211 are formed in the plate 20, and the fluid inlet part 22 and The three-dimensional microchannel 30 is formed at the center of the plate 20 between the fluid outlets 23. Fluid flows through the inlet 210, passes through the fluid inlet 22, between the microchannels 30, and exits through the fluid outlet 23 to the outlet 211.

Microchannel 30 according to the present invention is different from the conventional plate that forms concave grooves on only one side of the plate 20, as shown in enlarged in Figure 3 front surface 201 and both sides of the plate 20 and The concave grooves 31 and 32 are formed in both the rear surfaces 202. Specifically, as shown in FIG. 3, the front surface concave grooves 31 are formed in the plate front surface 201 at a predetermined interval, and the rear surface 202 also has the rear surface concave groove at a predetermined interval. The field 32 is formed. In the concave grooves 31 and 32, the spacing between the concave grooves does not need to be constant and may have various spacings depending on the design.

In addition, the front concave grooves 31 have a predetermined inclination with respect to the straight line of the edge of the plate 20, the rear concave grooves 32 and the forming direction of the front concave grooves 31 Is formed in a shifting direction. The front concave grooves 31 and the rear concave grooves 32 are formed to have a predetermined depth, and the bottom of the front concave grooves 31 and the bottom of the rear concave grooves 32 are formed. In the portion where the space is formed, a plurality of spaces 33 passing through the front and rear are formed, and the space 33 is a mixture where the fluid passing through the front concave grooves 31 and the fluid passing through the rear surface concave grooves 32 meet. It becomes the space 33. The concave grooves 31 and 32 may have an irregular pattern according to a regular pattern or a design, and preferably have a pattern in which the mixing space 33 penetrating the plate 20 is formed.

As shown in FIG. 4, since the fluid reaching the mixing space 33 through the front concave grooves 31 moves to the expanded space in a narrow space, vortices having a direction different from the main flow direction 2 may have a different direction from the main flow direction, such as a change in the direction of the streamline because it is mixed with the fluid passing through the rear concave grooves 32 introduced into the mixing space 33. Vortex, the secondary flow, is generated. Since the secondary flow, which is the secondary flow, causes heat transfer more actively than laminar flow, the three-dimensional microchannel according to the present invention has a higher heat transfer efficiency than the conventional vortex.

3 to 6, the pattern of the micro channel may have a regular pattern to easily form the front concave grooves 31 and the rear concave grooves 32 in large quantities. The regular pattern may be formed on both surfaces or both surfaces of at least one of the front concave grooves 31 and the rear concave grooves 32. In addition, the patterns of the concave grooves 31 and 32 formed on both surfaces may have different pattern shapes, and may have the same pattern. 3 to 6 illustrate a case in which the concave grooves 31 and 32 formed on both surfaces have the same pattern. At this time, after processing the pattern of the front concave grooves 31 on the front surface 201 regularly, the rear surface concave grooves 32 are formed by inverting the plate 20 and processing the same pattern on the rear surface 202. It is formed to facilitate the processing. Even in this case, the rear concave grooves 32 processed on the rear surface 202 have a shape that is shifted from the front concave grooves 31 when viewed from the front, and the front concave grooves 31 and the rear surface. The mixing space 33 penetrating the plate 20 is formed at a portion where the bottoms of the concave grooves 32 meet.

When the front concave grooves 31, the rear concave grooves 32, and the mixing space 33 are processed, the fluid inlet portion 21 and the fluid outlet portion 22 may be processed together. Since the fluid inlet part 21 and the fluid outlet part 22 have a perforated shape unlike the conventional art, the fluid inlet part 21 and the fluid outlet part 22 may flow fluid into the front concave grooves 31 and the rear concave grooves 32. .

For example, as shown in FIG. 3, the micro channel 30 has the front concave grooves 31 formed in an inclined pattern with a predetermined inclination. The micro channel 30 is inverted to form the rear concave grooves 32 in the same pattern. I can process it. In addition, as illustrated in FIG. 5, the front concave grooves 31 formed on the front surface 201 are repeated with the straight portion 311 and the inclined portion 312 inclined at a predetermined inclination along the concave groove. It is possible to process the shape to be, and to process the rear concave grooves 32 of the rear surface 202 in the same pattern. The mixing space 33, which is a portion where the front concave grooves 31 and the rear concave grooves 32 meet, is made in the shape of a hexagon. As shown in FIG. 6, the hexagonal mixing space 33 has the front concave grooves 31 and the rear concave grooves 32 in which fluids having an inclination with each other recombine, flow in a straight direction, and then neighbor again. Since the flow is divided into the front concave grooves 31 and the rear concave grooves 32, a change in the streamline direction of the fluid may occur rapidly, thereby generating more vortices that are secondary flows.

In addition, as shown in (a) to (c) of FIG. 7, the pattern formed by the front concave grooves 31 and the rear concave grooves 32 has a structure that forms a plurality of V-shaped or V-shaped as a whole. Branches can have a regular array. As described above, the front concave grooves 31 and the rear concave grooves 32 may have different patterns. For example, when the front concave grooves 31 are the inclined pattern of FIG. 3, the rear concave grooves 32 may have the pattern of FIG. 5 or the pattern of FIG. 7.

The front concave grooves 31 and the rear concave grooves 32 forming the three-dimensional micro channel 30 may be manufactured by a chemical etching method. That is, the pattern of the microchannel 30 to be formed on the front surface 201 and the rear surface 202 of the plate 20 is etched by using a corrosion solution with respect to the pattern so that only the portion where the pattern is etched is etched. In this case, the front concave grooves 31 and the rear concave grooves 32, and the perforated mixing space 33, the fluid inlet 22 and the outlet 23 can be formed.

Referring to FIG. 8, it can be seen that the heat exchanger is constructed by stacking several plates 20 having three-dimensional microchannels 30 according to the present invention. In the plate 20 according to the present invention, since the mixing space 33, the fluid inlet part 22, and the outlet part 23 in the microchannel 30 are perforated as described above, the plate 20 has a large number of the plates 20. The diaphragm 40 is provided between one plate 20a and the adjacent plate 20b in order to stack them and prevent the fluid flowing through the microchannel 30 from flowing into the neighboring plate 20. The diaphragms 40 have through holes 41 formed at four corners, and the through holes 41 function as a passage through which fluid flows.

The heat exchanger according to the present invention is arranged such that the plates 20a with the three-dimensional microchannels are in opposite directions with the neighboring plates 20b and the fluids. Specifically, in FIG. 8, the odd-numbered plates 20a and 20c are arranged to move the fluid from the upper right to the lower left, and the even-numbered plates 20b and 20d are arranged to move the fluid from the upper left to the lower right. do.

In addition, the high temperature fluid flows through the odd-numbered plates 20a and 20c, and the low temperature fluid flows through the even-numbered plates 20b and 20b so that the high-temperature fluid and the low-temperature fluid flow into the three-dimensional microplates of the plates. Allows heat exchange with neighboring plates while passing through channel 30.

In this case, since the plate according to the present invention forms a three-dimensional microchannel, the fluid generates secondary flow such as vortex to smoothly mix the fluid in the channel, thereby improving heat transfer efficiency.

As described above, the present invention includes a three-dimensional microchannel in which fluid moves in a plate, and fluids having different flow directions are mixed in a mixing space to generate vortices that are secondary flows different from the main flow direction. Allows the heat exchange with the fluid flowing in the plate to proceed actively.

In addition, the present invention has the advantage of easy processing by being able to form a mirror-symmetrical concave groove with the same pattern on the front and rear surfaces of the plate.

The above-described embodiment is merely one example of a technical idea according to the present invention, the technical idea of the present invention is defined by the contents described in the claims to be described later, and those skilled in the art can easily design changes through the embodiments It includes the range that it is.

Claims (11)

It is laminated to the heat exchanger, and has a fluid inlet and a fluid outlet in partial communication with the inlet and the outlet formed in the diagonal corner, the fluid inlet formed between the fluid inlet and the fluid outlet inlet fluid inlet A plate having microchannels for flowing from the fluid outlet to the outlet, The micro channel is: A plurality of front concave grooves arranged on the front surface of the plate at predetermined intervals; A plurality of rear surface concave grooves arranged on the rear surface of the plate at predetermined intervals, the rear surface concave grooves being formed in a direction that is displaced from a direction in which the front concave grooves are formed; And The plate penetrates through a portion where the bottom of the front concave grooves and the bottom of the rear concave grooves are formed so as to deviate from the front concave grooves, thereby forming a fluid flowing through the front concave groove and the rear concave groove. A plate having a three-dimensional microchannel, characterized in that it has a plurality of mixing spaces to allow the flowing fluid to be mixed. The method of claim 1, Concave grooves formed in at least one of the front and rear concave grooves formed on the front and rear surfaces of the plate to form the micro channel has a regular pattern arranged at regular intervals 3D microchannel formed plate. The method of claim 2, The front concave grooves and the rear concave grooves are formed to have the same pattern, and when viewed from the front, the front concave grooves and the rear concave grooves are mirror symmetric with each other. plate. The method of claim 2, The pattern is a plate with a three-dimensional micro-channel, characterized in that the concave grooves are inclined straight to have a predetermined slope. The method of claim 2, The pattern is a plate formed with a three-dimensional micro-channel, characterized in that the concave grooves have a shape in which the straight portion and the inclined portion having an inclination is repeated continuously. The method of claim 2, The pattern is a plate formed with a three-dimensional micro-channel, characterized in that the concave grooves form a V-shape as a whole. The method of claim 3, The pattern is a plate with a three-dimensional micro-channel, characterized in that the concave grooves are inclined straight to have a predetermined slope. The method of claim 3, The pattern is a plate formed with a three-dimensional micro-channel, characterized in that the concave grooves have a shape in which the straight portion and the inclined portion having an inclination is repeated continuously. The method of claim 3, The pattern is a plate formed with a three-dimensional micro-channel, characterized in that the concave grooves form a V-shape as a whole. The method according to any one of claims 1 to 9, The front concave grooves and the rear concave grooves of the micro channel are formed by etching method. A plurality of plates having three-dimensional microchannels according to any one of claims 1 to 9 are stacked, and stacked so as to be located in opposite directions of the inlet and the outlet. A plate between the plates to prevent fluid from flowing between the plates, The diaphragm is a heat exchanger using a plate formed with a three-dimensional micro-channel, characterized in that the through-hole is formed in four corners.

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