CN111900143A - A manifold type high aspect ratio microchannel heat exchanger - Google Patents

Abstract

The invention discloses a manifold type high aspect ratio micro-channel heat exchanger, comprising an upper cover plate, a manifold device and a micro-channel heat sink, the upper cover plate is covered above the micro-channel heat sink, and the first There is an inner cavity on one surface, the manifold device is arranged on the top wall of the inner cavity, the first surface of the microchannel heat sink is provided with a micro-rib wall corresponding to the position of the manifold device, and the manifold device is connected with The micro-rib wall is attached up and down and accommodated in the inner cavity. The micro-rib wall forms several parallel channels with high aspect ratio along the flow direction of the cooling liquid. The manifold device and several channels form a manifold jet micro-channel cavity. The manifold The device can strengthen the disturbance of the flow in the microchannel, strengthen the heat exchange, realize the jet cooling method, and make the temperature distribution at the bottom of the heat sink more uniform. The high aspect ratio channel is closely connected with the manifold device, which can increase the heat exchange area and provide a large number of bubbles The nucleation point further improves the heat transfer effect and effectively reduces the pressure drop.

Description

A manifold type high aspect ratio microchannel heat exchanger

technical field

The invention belongs to the field of microchannel heat exchanger design, in particular to a manifold type high aspect ratio microchannel heat exchanger.

Background technique

The high-speed integration and miniaturization of electronic equipment make the heat dissipation problem particularly significant. As early as 1981, some scholars proposed to use microchannels for heat exchange, which not only can meet the needs of high heat flux density, but also effectively solve the problem that the size of conventional channels is not suitable for Problems with Microelectronics. With the deepening of research on microchannel heat exchangers, microchannels with different structures have different effects on the heat transfer effect. Compared with single-phase flow, the boiling flow heat transfer in the microchannel has a more efficient heat transfer capacity. It makes full use of the latent heat of the phase change of the coolant, and the growth, detachment, and fragmentation of bubbles during the boiling process greatly improves the heat transfer coefficient. Electronic equipment to meet higher heat transfer requirements.

At present, most microchannel heat exchangers use low aspect ratio microchannel heat exchangers. Although they can improve the heat exchange effect, the heat exchange area is small, and the space provided for bubble nucleation is insufficient, resulting in limited heat exchange capacity. The smaller cross section of the flow channel causes a larger pressure drop when the coolant flows through the microchannel, resulting in an increase in its power consumption. Patent CN201921304518.9 discloses a high aspect ratio foam metal microchannel phase change cooling device compounded with an aluminum substrate, which adopts high aspect ratio microchannels to increase the heat exchange area, increase the vaporization core density, and effectively improve the heat transfer coefficient, but only The aspect ratio is 5 to 10, and the improvement of heat transfer effect is limited.

A large number of studies have found that there are still some problems in microchannel heat exchangers, such as uneven flow distribution of parallel microchannels, which leads to uneven temperature distribution at the bottom of microchannels, which is easy to increase local temperature, which in turn has adverse effects on electronic equipment. Patent CN201811088661.9 discloses a liquid-cooled heat dissipation device for a multi-manifold jet microchannel chip. Through the action of jets, on the one hand, the disturbance is enhanced and the heat exchange capacity is improved; Temperature uniformity at the bottom of the sink. However, this microchannel heat exchanger requires five structural modules to be superimposed, which requires high machining accuracy, and is prone to deviation during the alignment and installation process, which hinders the flow.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a manifold type high aspect ratio microchannel heat exchanger, which can strengthen the flow disturbance in the microchannel, realize the jet cooling method to strengthen the heat exchange, and make the temperature distribution at the bottom of the heat sink more uniform; Compared with microchannels, the heat exchange area is increased, a large number of bubble nucleation points are provided, the heat exchange effect is further improved, and the pressure drop is effectively reduced.

For solving the above problems, the technical scheme of the present invention is:

A manifold type high aspect ratio microchannel heat exchanger, comprising an upper cover plate, a manifold device and a microchannel heat sink, the upper cover plate is covered above the microchannel heat sink, and the upper cover The surfaces on which the plate is attached to the microchannel heat sink are respectively defined as the first surface of the upper cover plate and the first surface of the microchannel heat sink;

The upper cover plate is provided with a coolant inlet and a coolant outlet, and an inner cavity is defined on the first surface of the upper cover plate;

The manifold device is arranged on the top wall of the inner cavity, and the manifold device includes at least one liquid inlet flow channel and at least one liquid outlet flow channel;

The first surface of the micro-channel heat sink is provided with a micro-rib wall corresponding to the position of the manifold device. When the upper cover plate and the micro-channel heat sink are in a covered state, the manifold The tube device and the micro-rib wall are attached up and down to be accommodated in the inner cavity, and the inner cavity is divided into independent inlet liquid storage chambers and outlet liquid storage chambers, and the micro-rib walls are along the flow direction of the cooling liquid A plurality of high aspect ratio channels arranged in parallel are formed, the manifold device and a plurality of the channels constitute a manifold jet micro-channel cavity, and the liquid inlet channel is connected to the plurality of the channels one by one, so the The said liquid flow channel is connected with a plurality of said channels one by one;

The coolant inlet is communicated with the liquid inlet of the inlet liquid storage cavity, the liquid outlet of the inlet liquid storage cavity is communicated with the liquid inlet channel, and the cooling liquid enters the In the channel, the liquid outlet channel is communicated with the liquid inlet of the outlet liquid storage cavity, the liquid outlet of the outlet liquid storage cavity is communicated with the coolant outlet, and the cooling liquid that absorbs heat flows from the channel It is led out from the coolant outlet through the liquid outlet channel and the outlet liquid storage chamber in sequence.

Preferably, the manifold device is a curved rib disposed on the top wall of the inner cavity, two ends of the curved rib extend to connect with the side wall of the inner cavity, the The curved rib opening toward the inlet liquid storage chamber is the liquid inlet channel, and the curved rib opening facing the outlet liquid storage chamber is the liquid outlet channel.

Preferably, the manifold device is a W-shaped curved rib, and the W-shaped curved rib and the side wall of the inner cavity form two liquid inlet flow channels and three liquid outlet flow channels arranged alternately. .

Preferably, the liquid inlet channel is in the shape of a trapezoid tapering along the flow direction of the cooling liquid, and the liquid outlet channel near the side wall of the inner cavity is in the shape of a right-angled triangle that gradually expands along the flow direction of the cooling liquid, The liquid outlet channel away from the side wall of the inner cavity is in the shape of a trapezoid that gradually expands along the cooling liquid flow direction.

Preferably, the manifold device is integrally formed with the upper cover plate by means of electric spark technology.

Preferably, the aspect ratio of the channel is 25.

Preferably, the cross section of the channel is rectangular.

Preferably, the materials of the upper cover plate, the manifold device and the microchannel heat sink are all copper.

Preferably, a sealing groove corresponding to the inner cavity is formed on the first surface of the microchannel heat sink.

Compared with the prior art, the present invention has the following advantages and positive effects due to the adoption of the above technical solutions:

1) The present invention provides a manifold type high aspect ratio microchannel heat exchanger, including an upper cover plate, a manifold device and a microchannel heat sink, the upper cover plate is covered above the microchannel heat sink, and the upper cover plate is A coolant inlet and a coolant outlet are opened on the top, an inner cavity is opened on the first surface of the upper cover plate, the manifold device is arranged on the top wall of the inner cavity, and the first surface of the microchannel heat sink is provided with The position of the manifold device corresponds to the micro-rib wall. The manifold device and the micro-rib wall are stacked up and down and accommodated in the inner cavity. The micro-rib wall forms several parallelly arranged high aspect ratio channels along the cooling liquid flow direction. The manifold device It forms a manifold jet microchannel cavity with several channels. The manifold device can strengthen the disturbance of the flow in the microchannel, strengthen the heat exchange, realize the jet cooling method, and make the temperature distribution at the bottom of the heat sink more uniform. The manifold devices are closely connected, which can increase the heat exchange area, provide a large number of bubble nucleation points, further improve the heat exchange effect, and effectively reduce the pressure drop.

Description of drawings

1 is a schematic structural diagram of a manifold type high aspect ratio microchannel heat exchanger according to an embodiment of the present invention;

FIG. 2 is a schematic view of the rear structure of the cover plate in FIG. 1;

Fig. 3 is the top view of the back of the cover plate in Fig. 1;

Fig. 4 is the structural schematic diagram of the high aspect ratio microchannel heat sink in Fig. 1;

5 is a schematic diagram of the coolant flow principle of a manifold type high aspect ratio microchannel heat exchanger according to an embodiment of the present invention;

Description of reference numbers:

1: upper cover plate; 11: coolant inlet; 12: coolant outlet; 13: inner cavity; 131: inlet liquid storage chamber; 132: outlet liquid storage chamber; 14: upper cover plate threaded hole; 2: manifold device; 21: liquid inlet channel; 22: outlet channel; 221: main outlet channel; 222: auxiliary outlet channel; 3: micro-channel heat sink; 31: micro-rib wall; 311: channel; 32: Micro-channel heat sink threaded hole; 33: Seal groove.

Detailed ways

A manifold type high aspect ratio microchannel heat exchanger proposed by the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become apparent from the following description and claims.

1 to 5, the present invention provides a manifold type high aspect ratio microchannel heat exchanger, including an upper cover plate 1, a manifold device 2 and a microchannel heat sink 3, and the upper cover plate 1 is covered with Above the microchannel heat sink 3, the surfaces where the upper cover plate 1 and the microchannel heat sink 3 are bonded are respectively defined as the first surface of the upper cover plate 1 and the first surface of the microchannel heat sink 3;

The overall size of the upper cover plate 1 is 30mm*25mm, and the material is metal copper. The left and right sides of the upper cover plate 1 are respectively provided with a coolant inlet 11 and a coolant outlet 12 that pass through the upper cover plate 1. The coolant inlet 11 is far from the left side. The edge is 6.5mm, the distance from the front and rear edges is 12.5mm, the coolant outlet 12 is 6.5mm from the right edge, and the distance from the front and rear edges is 12.5mm, the diameter of the coolant inlet 11 and the coolant outlet 12 are both 5mm, see Figure 2 As shown, an inner cavity 13 is provided on the first surface of the upper cover 1, the depth of the inner cavity 13 is 7 mm, and the inner cavity 13 includes an inlet liquid storage cavity 131 and an outlet liquid storage cavity 132 (Description: marked in FIG. 1 ) 131 and 132 refer to the bottom of the inlet liquid storage chamber 131 and the outlet liquid storage chamber 132), the coolant inlet 11 communicates with the inlet liquid storage chamber 131, and the coolant outlet 12 communicates with the outlet liquid storage chamber 132;

In this embodiment, the upper cover plate 1 is also provided with a number of upper cover plate threaded holes 14, the upper cover plate 1 and the microchannel heat sink 3 are fixedly connected by threaded bolts, and the front and rear sides of the upper cover plate 1 are respectively provided with threaded holes 14. There are four upper cover threaded holes 14, and a total of eight upper cover threaded holes 14. In this embodiment, the specification of the upper cover threaded holes 14 is M2 threaded holes. Referring to FIG. 2, the microchannel heat sink 3 Eight micro-channel heat sink threaded holes 32 are opened at the positions corresponding to the threaded holes 14 of the upper cover plate. The specifications of the micro-channel heat sink threaded holes 32 are M2 threaded holes, and the upper cover plate 1 and the micro-channel heat sink 3 pass through. The threaded hole 14 of the upper cover plate is fastened with the threaded hole 32 of the microchannel heat sink.

Referring to FIG. 2, the manifold device 2 is arranged on the top wall of the inner cavity 13. The manifold device 2 includes at least one liquid inlet flow channel and at least one liquid outlet flow channel. The manifold device 2 is arranged in the inner cavity body. The curved convex rib on the top wall of 13, the two ends of the curved convex rib extend to connect with the side wall of the inner cavity 13, and the curved channel of the curved convex rib opening toward the inlet liquid storage cavity 131 is the liquid inlet flow channel, The curved rib opening toward the outlet liquid storage chamber 132 is the liquid outlet flow channel. Referring to FIG. 3 , in this embodiment, the manifold device 2 is a W-shaped curved rib. The size is 10mm*10mm, and it is located in the middle of the top wall of the inner cavity 13. The width of the curved rib is 1mm and the height is 2mm. The W-shaped curved rib and the side wall of the inner cavity 13 form two alternately arranged The liquid inlet flow channel 21 and the three liquid outlet flow channels 22, wherein the liquid inlet flow channel 22 is a trapezoid shape tapered along the cooling liquid flow direction, and the bottom edge of the liquid inlet flow channel 22 close to the side of the inlet liquid storage cavity 131 is 3mm, the bottom plate on the other side is 0.3mm, and the height is 9mm; the outflow channel 22 includes two main outflow channels 221 and one auxiliary outflow channel 222, and the two main outflow channels 221 are located in the inner cavity On the side wall of the body 13, the main outlet flow channel 221 is a right-angled triangle shape that gradually expands along the flow direction of the cooling liquid, the base of the right-angled triangle is 1.5mm, and the height is 10mm. In the middle of the channel 221, the auxiliary liquid flow channel 222 is a trapezoid shape that gradually expands along the flow direction of the cooling liquid. The upper bottom edge of the trapezoid is 0.3mm, the lower bottom edge is 3mm, and the height is 9mm;

In the present embodiment, the manifold device 2 is processed on the top wall of the inner cavity 13 by using electric spark technology, and is integrally formed with the upper cover plate 1 .

The overall size of the micro-channel heat sink 3 is 30mm*25mm, and the material is metal copper. The first surface of the micro-channel heat sink 3 is provided with a micro-rib wall 31 corresponding to the position of the manifold device 2. The manifold device 2 and The length and width of the micro-rib wall 31 are the same, and the total size of the micro-rib wall 31 is 10mm*10mm*5mm. When the upper cover plate 1 and the micro-channel heat sink 3 are in a closed state, the manifold device 2 and the micro-rib wall 31 The upper and lower fittings are accommodated in the inner cavity 13 without a gap in the middle. The manifold device 2 and the micro-rib wall 31 are fitted up and down to separate the inner cavity 13 into independent inlet liquid storage chambers 131 and outlet liquid storage chambers 132. The micro-ribs The wall 31 forms a plurality of high aspect ratio channels 311 arranged in parallel along the cooling liquid flow direction. The side micro-rib wall is 5000 μm high, 1100 μm wide, and 1000 μm long. The cross-section of the channel 311 is rectangular, there are 20 in total, the height is 5000 μm, the width is 200 μm, and the length is 1000 μm. The hydraulic diameter of the channel 311 is 385 μm and the aspect ratio is 25; The pipe device 2 and a plurality of channels 311 form a manifold jet micro-channel cavity, the liquid inlet channel 21 is connected with a number of channels 311 one by one, and the liquid outlet channel 22 is connected with a number of channels 311 one by one. In the example, the inlet flow channel 21 adopts a tapered manifold that tapers along the flow direction of the cooling liquid, which helps the cooling liquid to reach the microchannel farthest from the inlet, and the outlet flow channel 22 adopts a tapered manifold that gradually expands along the flow direction of the cooling liquid. The gradually expanding manifold helps the fluid to be effectively collected in the outlet liquid storage chamber 132;

The coolant inlet 11 is communicated with the liquid inlet of the inlet liquid storage chamber 131, the liquid outlet of the inlet liquid storage chamber 131 is connected with the liquid inlet channel 21, and the coolant enters the channel 311 through the jet flow of the liquid inlet channel 21, and the liquid is discharged. The flow channel 22 is communicated with the liquid inlet of the outlet liquid storage cavity 132, and the liquid outlet of the outlet liquid storage cavity 132 is communicated with the coolant outlet 12. The cooling liquid that absorbs heat passes from the channel 311 through the liquid outlet flow channel 22 and the outlet storage cavity in sequence. The liquid chamber 132 leads from the coolant outlet 12 .

Preferably, a sealing groove 33 corresponding to the inner cavity 13 is formed on the first surface of the microchannel heat sink 3 .

Referring to FIG. 5 , the working principle of the heat exchanger provided by the present invention is that the flow direction of the coolant is shown by the arrow in the figure, the coolant flows from the coolant inlet 11 into the inlet liquid storage chamber 131, and the inlet liquid storage chamber 131 is filled with After the coolant, it flows into the liquid inlet channel 21 in the horizontal direction, and then flows into the channel 311 in the vertical direction. In the liquid flow channel 22 , the coolant flows in the liquid outlet flow channel 22 along the horizontal direction and collects into the outlet liquid storage cavity 132 , and flows out of the micro-channel heat exchanger through the coolant outlet 12 .

The present invention provides a manifold type high aspect ratio microchannel heat exchanger, comprising an upper cover plate 1, a manifold device 2 and a microchannel heat sink 3, and the upper cover plate 1 is covered above the microchannel heat sink 3 , the upper cover plate 1 is provided with a coolant inlet 11 and a coolant outlet 12, an inner cavity 13 is provided on the first surface of the upper cover plate 1, the manifold device 2 is arranged on the top wall of the inner cavity 13, and the micro The first surface of the channel heat sink 3 is provided with a micro-rib wall 31 corresponding to the position of the manifold device 2. The manifold device 2 and the micro-rib wall 31 are stacked and accommodated in the inner cavity 13 up and down. The flow direction of the cooling liquid forms a plurality of high aspect ratio channels 311 arranged in parallel. The manifold device 2 and the plurality of channels 311 form a manifold jet microchannel cavity. The high aspect ratio channel is closely connected with the manifold device, which can increase the heat exchange area, provide a large number of bubble nucleation points, further improve the heat exchange effect, and effectively Reduce pressure drop.

The embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above-mentioned embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and the technical equivalents thereof, they still fall within the protection scope of the present invention.

Claims (9)

1. A manifold type high aspect ratio microchannel heat exchanger is characterized by comprising an upper cover plate, a manifold device and a microchannel heat sink, wherein the upper cover plate covers the upper part of the microchannel heat sink, and the surfaces of the upper cover plate, which are attached to the microchannel heat sink, are respectively defined as a first surface of the upper cover plate and a first surface of the microchannel heat sink;

the upper cover plate is provided with a coolant inlet and a coolant outlet, and the first surface of the upper cover plate is provided with an inner cavity;

the manifold device is arranged on the top wall of the inner cavity and comprises at least one liquid inlet flow channel and at least one liquid outlet flow channel;

the first surface of the microchannel heat sink is provided with a micro-rib wall corresponding to the position of the manifold device, when the upper cover plate and the microchannel heat sink are in a covering state, the manifold device and the micro-rib wall are vertically attached and accommodated in the inner cavity and divide the inner cavity into an independent inlet liquid storage cavity and an independent outlet liquid storage cavity, the micro-rib wall forms a plurality of high depth-width ratio channels which are arranged in parallel along the flowing direction of cooling liquid, the manifold device and the plurality of channels form a manifold type jet flow microchannel cavity, the liquid inlet channels are communicated with the plurality of channels one by one, and the liquid outlet channels are communicated with the plurality of channels one by one;

the coolant entry with the inlet intercommunication in entry stock solution chamber, the liquid outlet in entry stock solution chamber with the feed liquor runner intercommunication, the coolant liquid warp the feed liquor runner efflux gets into in the channel, go out the liquid runner with the inlet intercommunication in export stock solution chamber, the liquid outlet in export stock solution chamber with coolant outlet intercommunication, the thermal coolant liquid of absorption is followed the channel passes through in proper order go out the liquid runner export stock solution chamber is followed the coolant outlet is derived.

2. The manifolded high aspect ratio microchannel heat exchanger according to claim 1, wherein the manifolding is a curved rib disposed on the top wall of the inner chamber, the curved rib extending from both ends to connect to the side wall of the inner chamber, the curve of the curved rib opening into the inlet reservoir being the inlet channel, and the curve of the curved rib opening into the outlet reservoir being the outlet channel.

3. The manifolded high aspect ratio microchannel heat exchanger of claim 2, wherein the manifolding is a W-shaped curved rib, the W-shaped curved rib and the sidewall of the internal cavity defining two inlet channels and three outlet channels in alternating alignment.

4. The manifolded high aspect ratio microchannel heat exchanger of claim 3, wherein the inlet channels are trapezoidal in shape that tapers in the direction of coolant flow, the outlet channels near the sidewall of the inner cavity are right triangular in shape that tapers in the direction of coolant flow, and the outlet channels away from the sidewall of the inner cavity are trapezoidal in shape that tapers in the direction of coolant flow.

5. The manifolded high aspect ratio microchannel heat exchanger of claim 2, 3, or 4, wherein the manifolding is integrally formed with the upper cover plate using an electrical discharge technique.

6. The manifolded high aspect ratio microchannel heat exchanger according to claim 1, wherein the channel has an aspect ratio of 25.

7. The manifolded high aspect ratio microchannel heat exchanger according to claim 1, wherein the channels are rectangular in cross-section.

8. The manifolded high aspect ratio microchannel heat exchanger according to claim 1, wherein the upper cover plate, the manifold device, and the microchannel heat sink are all copper.

9. The manifolded high aspect ratio microchannel heat exchanger of claim 1, wherein the first surface of the microchannel heat sink is provided with a sealing groove corresponding to the internal cavity.

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