A microchannel heat exchange panel and heat exchanger suitable for phase change heat transfer

Abstract

The present invention provides a microchannel heat exchange panel and a heat exchanger suitable for phase change heat exchange, the microchannel heat exchange panel suitable for phase change heat exchange comprises: a plate body and a heat exchange channel arranged on the plate body, the heat exchange channel is provided with a plurality of channels, the heat exchange channel comprises an inlet section, a preheating section, an evaporation section, a superheating section and an outlet section, the inlet section, the preheating section, the evaporation section, the superheating section and the outlet section are connected in sequence, the evaporation section comprises a first separation section and a second evaporation section, the first separation section is connected with the second evaporation section in sequence, the first separation section is used to separate the gas and liquid of the fluid flowing through, and the second evaporation section is used to evaporate all the liquid phase fluid after the gas-liquid separation. The present invention can ensure the advantages of large heat exchange specific surface area and high heat exchange efficiency of the original microchannel heat exchange panel, and at the same time make the microchannel heat exchange panel applicable to the heat exchange of fluid with phase change process, and realize the automatic separation of gas and liquid phases in the evaporation process.

Description

Technical field:

[0001] The present invention relates to the technical field of heat exchange, and in particular to a microchannel heat exchange panel and a heat exchanger suitable for phase change heat exchange. Background technology:

[0002] In the field of heat exchange technology, the current microchannel heat exchanger is a new type of high-efficiency heat exchanger composed of a heat exchange core, a head, a pipe, and a flange. It features high compactness, small size, high structural strength, high heat exchange efficiency, high temperature and pressure resistance, and designable heat exchange channels. Microchannel heat exchangers were first used in the aerospace and aviation fields for cooling aircraft or engine surfaces. However, with the maturity of processing technology, microchannel heat exchangers also have great potential for use in the field of civilian energy conservation. Therefore, microchannel heat exchangers are not only highly regarded in the field of heat exchange technology, but also a hot research and development topic in the energy and power industry.

[0003] The heat exchange core of the existing microchannel heat exchanger is a packaged whole composed of hot and cold plates with flow channels placed alternately and fixed together by diffusion welding. Among them, the hot and cold plates with flow channels are of uniform configuration, and the form of their channels can be semicircular or rectangular grooves, using herringbone corrugations or sinusoidal corrugations as the waveform. The above-mentioned classic design of the hot and cold plate flow channels can achieve fluid heat exchange enhancement and a higher specific heat exchange surface. However, in the heat exchange process with phase change, especially when the liquid is converted to gas, the uniform configuration of the flow channel will generate high pressure, thereby inhibiting and delaying the occurrence of the phase change process, resulting in the microchannel being unable to be effectively utilized in the phase change heat exchange, resulting in a low heat transfer area density and a lack of microchannel heat exchangers that can meet the phase change heat exchange requirements.

[0004] Therefore, there is an urgent need in the art for a microchannel heat exchange panel and a heat exchanger suitable for phase change heat transfer.

[0005] In view of this, the present invention is proposed. Summary of the invention:

[0006] The object of the present invention is to provide a microchannel heat exchange panel and a heat exchanger suitable for phase change heat exchange with better use effect, so as to solve at least one technical problem in the prior art.

[0007] Specifically, a first aspect of the present invention provides a microchannel heat exchange panel suitable for phase change heat exchange, the microchannel heat exchange panel suitable for phase change heat exchange comprises: a plate body and a heat exchange channel arranged on the plate body, the heat exchange channel is provided with multiple, the heat exchange channel comprises an inlet section, a preheating section, an evaporation section, a superheating section and an outlet section, the inlet section, preheating section, evaporation section, superheating section and outlet section are connected in sequence, the inlet section is used for the heat exchange liquid to enter the heat exchange channel, the preheating section is used to preheat the fluid flowing through this section so that it absorbs heat and is converted into a gas-liquid two-phase fluid, the evaporation section is used to completely evaporate the fluid flowing through this section, the superheating section is used to allow the completely evaporated fluid to continue to absorb heat, and the outlet section is used for the fluid to flow out of the heat exchange channel after the heat exchange is completed, the evaporation section comprises a first separation section and a second evaporation section, the first separation section is connected to the second evaporation section in sequence, the first separation section is used to separate the fluid flowing through from gas and liquid, and the second evaporation section is used to completely evaporate the liquid phase fluid after the gas-liquid separation.

[0008] The above structure ensures the advantages of the original microchannel heat exchange panel, such as large heat exchange specific surface area and high heat exchange efficiency. At the same time, the microchannel heat exchange panel can be applied to the heat exchange of fluids with phase change process, realizes automatic separation of gas and liquid phases during evaporation, maintains the heat transfer area density at a high level, and ensures that the phase change heat exchange process proceeds in an orderly manner, so that the microchannel heat exchange panel can be effectively utilized in phase change heat exchange.

[0009] Preferably, an overflow weir and sieve holes are provided in the first separation section. In the first separation section, the sieve holes are provided after the overflow weir. There are multiple sieve holes. The overflow weir is connected to the inner wall of the heat exchange channel and protrudes from the inner wall of the heat exchange channel. The overflow weir is used to intercept and store unevaporated liquid phase fluid. The sieve holes are provided on the side wall of the heat exchange channel and can connect two adjacent heat exchange channels. The sieve holes are used for the evaporated gas phase fluid to pass through by relying on buoyancy and concentrate in the upper channel at the first separation section to achieve gas-liquid phase separation.

[0010] Furthermore, the overflow weir extends in the opposite direction to the direction of gravity exerted on the first separation section.

[0011] Furthermore, the overflow weir can reduce the cross-sectional area of ​​the location where the overflow weir is provided by 1 / 3-2 / 3.

[0012] Furthermore, the axis of the sieve hole coincides with the direction of gravity at the first separation section.

[0013] With the above structure, in actual use, when the gas-liquid mixed fluid flows through the first separation section, first, due to the action of gravity, the liquid phase fluid is concentrated at the bottom of the channel and is intercepted and stored by the overflow weir. The liquid phase fluid to be intercepted and stored by the overflow weir evaporates into gas and floats up from the overflow weir, or the liquid phase fluid to be intercepted and stored is exhausted and overflows from the overflow weir. The overflowed liquid phase fluid continues to flow in the channel. When passing through the sieve holes, it is concentrated by gravity through the sieve holes to the lower channel, thereby realizing the collection of the liquid phase fluid. Secondly, due to the action of gravity, the gas phase fluid is concentrated at the top of the channel and will not be intercepted by the overflow weir. It flows forward through the space at the top of the overflow weir. When the gas phase fluid in the lower channel passes through the sieve holes, it is concentrated by gravity through the sieve holes to the upper channel, thereby realizing the collection of the gas phase fluid, thereby completing the gas-liquid phase separation.

[0014] Preferably, the second evaporation section includes a gas phase channel and a liquid phase channel, and the gas phase channel and the liquid phase channel are arranged in parallel. The gas phase channel is connected to the upper channel of the first separation section, and the liquid phase channel is connected to the lower channel of the first separation section. The cross-sectional area of ​​the gas phase channel is larger than the cross-sectional area of ​​the liquid phase channel. There are multiple liquid phase channels arranged in parallel, and they are connected to the lower channel of the same first separation section.

[0015] Furthermore, two liquid phase channels are arranged in parallel.

[0016] By adopting the above structure, in actual use, automatic separation of gas and liquid phases can be achieved in the first separation section. The heat exchange channel of this section is divided into two layers, the upper layer's heat exchange channel for gas phase fluid circulates, and the lower layer's heat exchange channel for liquid phase fluid circulates. In the second evaporation section, the lower layer's heat exchange channel is connected to multiple liquid phase channels, which increases the local heat transfer coefficient and facilitates the complete evaporation of the liquid phase fluid.

[0017] Preferably, the cross-sectional area of ​​the superheating channel provided at the superheating section is smaller than the cross-sectional area of ​​the channel at the preheating section, and the number of superheating channels at the superheating section is greater than the number of channels at the preheating section.

[0018] Furthermore, one of the gas phase channels is connected to a plurality of superheat channels.

[0019] Furthermore, one of the gas phase channels is connected to two superheating channels.

[0020] Furthermore, the number of superheating channels in the superheating section is 2-3 times the number of heat exchange channels in the preheating section.

[0021] The above structure can increase the local heat transfer coefficient in the superheating section, ensure superheating at the lowest pressure drop of the gas, and enable the heat in the superheating section to be fully absorbed, thereby ensuring that all evaporated gas phase fluid continues to absorb heat after entering the superheating section. In addition, by changing the channel sizes of the preheating section, evaporation section, and superheating section in the same microchannel heat exchange panel, efficient heat exchange of fluids in different phases can be achieved in the same channel plate.

[0022] Specifically, a second aspect of the present invention provides a heat exchanger, which includes the above-mentioned microchannel heat exchange panel suitable for phase change heat transfer.

[0023] In summary, the present invention has the following beneficial effects:

[0024] 1. This invention maintains the advantages of the existing microchannel heat exchange panel, namely, large heat exchange specific surface area and high heat exchange efficiency. At the same time, it makes the microchannel heat exchange panel suitable for heat exchange of fluids with phase change processes. It achieves automatic separation of gas and liquid phases during evaporation, maintains a high heat transfer area density, and ensures that the phase change heat exchange process proceeds in an orderly manner, effectively utilizing the microchannel heat exchange panel in phase change heat exchange.

[0025] 2. The present invention can increase the local heat transfer coefficient in the superheating section, ensuring superheating at the lowest gas pressure drop, allowing the heat in the superheating section to be fully absorbed, thereby ensuring that all evaporated gas phase fluid continues to absorb heat after entering the superheating section. Moreover, by changing the channel sizes of the preheating section, evaporation section, and superheating section in the same microchannel heat exchange panel, efficient heat exchange of fluids in different phases can be achieved in the same channel plate. Description of the drawings:

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 A schematic diagram of an embodiment of a microchannel heat exchange panel suitable for phase change heat exchange according to the present invention;

[0028] Figure 2 Schematic diagram of another embodiment of a microchannel heat exchange panel suitable for phase change heat exchange according to the present invention;

[0029] Figure 3 for Figure 2 A partial enlarged view of .

[0030] Description of reference numerals:

[0031] Through the above description of the accompanying drawings, combined with the embodiments of the present invention, the technical solutions of the present invention can be more clearly understood and explained.

[0032] 1. Plate body; 2. Heat exchange channel; 21. Inlet section; 22. Preheating section; 23. Evaporation section; 231. First separation section; 2311. Overflow weir; 2312. Sieve hole; 232. Second evaporation section; 2321. Gas phase channel; 2322. Liquid phase channel; 24. Superheating section; 241. Superheating channel; 25. Outlet section. Specific implementation method:

[0033] Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. In the following description, when referring to the drawings, like numbers in different figures represent like or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible embodiments consistent with the present invention. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present invention, as detailed in the appended claims.

[0034] The terms used in this invention are for the purpose of describing specific embodiments only and are not intended to limit the invention. The singular forms "a," "the," and "the" used in this invention and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0035] The present invention will be described in detail below through examples.

[0036] like Figure 1 and Figure 2As shown, the present invention provides a microchannel heat exchange panel suitable for phase change heat exchange, the microchannel heat exchange panel suitable for phase change heat exchange comprises: a plate body 1 and a heat exchange channel 2 provided on the plate body 1, the heat exchange channel 2 is provided with a plurality of, the heat exchange channel 2 comprises an inlet section 21, a preheating section 22, an evaporation section 23, a superheating section 24 and an outlet section 25, the inlet section 21, the preheating section 22, the evaporation section 23, the superheating section 24 and the outlet section 25 are connected in sequence, the inlet section 21 is used for the heat exchange fluid to enter the heat exchange channel 2, the preheating section 22 is used to preheat the fluid flowing through this section , so that it absorbs heat and is converted into a gas-liquid two-phase fluid. The evaporation section 23 is used to evaporate all the fluid flowing through this section. The superheating section 24 is used to allow the completely evaporated fluid to continue to absorb heat. The outlet section 25 is used for the fluid to flow out of the heat exchange channel 2 after the heat exchange is completed. The evaporation section 23 includes a first separation section 231 and a second evaporation section 232. The first separation section 231 is connected to the second evaporation section 232 in sequence. The first separation section 231 is used to separate the flowing fluid into gas and liquid, and the second evaporation section 232 is used to evaporate all the liquid phase fluid after the gas-liquid separation.

[0037] The above structure ensures the advantages of the original microchannel heat exchange panel, such as large heat exchange specific surface area and high heat exchange efficiency. At the same time, the microchannel heat exchange panel can be applied to the heat exchange of fluids with phase change process, realizes automatic separation of gas and liquid phases during evaporation, maintains the heat transfer area density at a high level, and ensures that the phase change heat exchange process proceeds in an orderly manner, so that the microchannel heat exchange panel can be effectively utilized in phase change heat exchange.

[0038] like Figure 2 and Figure 3 As shown, the first separation section 231 is provided with an overflow weir 2311 and a sieve hole 2312. In the first separation section 231, the sieve hole 2312 is provided after the overflow weir 2311. There are multiple sieve holes 2312. The overflow weir 2311 is connected to the inner wall of the heat exchange channel 2 and protrudes from the inner wall of the heat exchange channel 2. The overflow weir 2311 is used to intercept and store the unevaporated liquid phase fluid. The sieve hole 2312 is provided on the side wall of the heat exchange channel 2. , which can connect two adjacent heat exchange channels 2. The sieve holes 2312 are used for the evaporated gas phase fluid to pass through by relying on buoyancy and concentrate in the upper channel at the first separation section 231 to achieve gas-liquid phase separation. The overflow weir 2311 extends in the opposite direction of the gravity direction at the first separation section 231. The overflow weir 2311 can reduce the cross-sectional area of ​​the location where it is set by 1 / 2. The axis of the sieve hole 2312 coincides with the gravity direction at the first separation section 231.

[0039] With the above structure, in actual use, when the gas-liquid mixed fluid flows through the first separation section 231, first, due to the action of gravity, the liquid phase fluid is concentrated at the bottom of the channel and is intercepted and stored by the overflow weir 2311. The liquid phase fluid intercepted and stored by the overflow weir 2311 evaporates into gas and floats up from the overflow weir 2311, or the liquid phase fluid overflows from the overflow weir 2311 when the intercepted storage space is exhausted. The overflowed liquid phase fluid continues to flow in the channel. When passing through the sieve hole 2312, it is concentrated by gravity through the sieve hole 2312 to the lower channel, thereby realizing the collection of the liquid phase fluid. Secondly, due to the action of gravity, the gas phase fluid is concentrated at the top of the channel and will not be intercepted by the overflow weir 2311. It flows forward through the space at the top of the overflow weir 2311. When the gas phase fluid in the lower channel passes through the sieve hole 2312, it is concentrated by gravity through the sieve hole 2312 to the upper channel, thereby realizing the collection of the gas phase fluid, thereby completing the gas-liquid phase separation.

[0040] In some preferred embodiments of the present invention, the overflow weir 2311 can reduce the cross-sectional area of ​​the location where it is set by 1 / 3.

[0041] In some preferred embodiments of the present invention, the overflow weir 2311 can reduce the cross-sectional area of ​​the location where it is set by 2 / 3.

[0042] like Figure 2 and Figure 3 As shown, the second evaporation section 232 includes a gas phase channel 2321 and a liquid phase channel 2322, and the gas phase channel 2321 and the liquid phase channel 2322 are arranged in parallel. The gas phase channel 2321 is connected to the upper channel of the first separation section 231, and the liquid phase channel 2322 is connected to the lower channel of the first separation section 231. The cross-sectional area of ​​the gas phase channel 2321 is larger than the cross-sectional area of ​​the liquid phase channel 2322. Two liquid phase channels 2322 are arranged in parallel and are connected to the lower channel of the same first separation section 231.

[0043] By adopting the above structure, in actual use, automatic separation of gas and liquid phases can be achieved at the first separation section 231. The heat exchange channel 2 of this section is divided into two layers, the upper layer's heat exchange channel 2 is used for gas phase fluid, and the lower layer's heat exchange channel 2 is used for liquid phase fluid. In the second evaporation section 232, the lower layer's heat exchange channel 2 is connected to multiple liquid phase channels 2322, which increases the local heat transfer coefficient and facilitates the complete evaporation of the liquid phase fluid.

[0044] like Figure 2 and Figure 3As shown, the cross-sectional area of ​​the superheating channel 241 provided at the superheating section 24 is smaller than the cross-sectional area of ​​the channel at the preheating section 22, and the number of the superheating channels 241 at the superheating section 24 is greater than the number of the channels at the preheating section 22, one gas phase channel 2321 is connected to two superheating channels 241, and the number of the superheating channels 241 at the superheating section 24 is twice the number of the heat exchange channels 2 at the preheating section 22.

[0045] The above structure can increase the local heat transfer coefficient at the superheating section 24, ensure superheating at the lowest pressure drop of the gas, and enable the heat at the superheating section 24 to be fully absorbed, thereby ensuring that all evaporated gas phase fluids continue to absorb heat after entering the superheating section 24. In addition, by changing the channel sizes of the preheating section 22, the evaporation section 23, and the superheating section 24 in the same microchannel heat exchange panel, efficient heat exchange of fluids in different phases can be achieved in the same channel plate.

[0046] In some preferred embodiments of the present invention, the number of the superheating channels 241 in the superheating section 24 is three times the number of the heat exchange channels 2 in the preheating section 22 .

[0047] In some preferred embodiments of the present invention, the number of channels at the outlet section 25 is greater than the number of channels at the inlet section 21 .

[0048] In some preferred embodiments of the present invention, the number of channels at the outlet section 25 is equal to the number of heat exchange channels 2 at the preheating section 22 .

[0049] In some preferred embodiments of the present invention, the cross section of the heat exchange channel 2 can be one of a semicircular, rectangular, trapezoidal, inverted trapezoidal, triangular, and elliptical shape.

[0050] In some preferred embodiments of the present invention, the channels in the preheating section 22, the second evaporation section 232 and the superheating section 24 adopt one or both of herringbone corrugations and sinusoidal corrugations.

[0051] Specifically, a second aspect of the present invention provides a heat exchanger, which includes the above-mentioned microchannel heat exchange panel suitable for phase change heat transfer.

[0052] In summary, the present invention can ensure the advantages of the original microchannel heat exchange panel, such as large heat exchange specific surface area and high heat exchange efficiency, while making the microchannel heat exchange panel suitable for fluid heat exchange with phase change process, realizing automatic separation of gas and liquid phases during the evaporation process, maintaining the heat transfer area density at a high level, and ensuring that the phase change heat exchange process proceeds in an orderly manner, so that the microchannel heat exchange panel is effectively utilized in the phase change heat exchange; the present invention can increase the local heat transfer coefficient at the superheating section 24, ensure superheating under the minimum pressure drop of the gas, so that the heat at the superheating section 24 can be fully absorbed, thereby ensuring that all evaporated gas phase fluids continue to absorb heat after entering the superheating section 24, and by changing the channel sizes of the preheating section 22, the evaporation section 23, and the superheating section 24 in the same microchannel heat exchange panel, efficient heat exchange of fluids of different phases in the same channel plate can be achieved.

[0053] It should be pointed out that for ordinary technicians in this field, several improvements and modifications can be made to the present invention without departing from the principles of the present invention. These improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A microchannel heat exchange panel suitable for phase change heat exchange, characterized in that: The microchannel heat exchange panel suitable for phase change heat exchange comprises: a plate body and a heat exchange channel (2) arranged on the plate body (1), wherein a plurality of heat exchange channels (2) are arranged, wherein the heat exchange channel (2) comprises an inlet section (21), a preheating section (22), an evaporation section (23), a superheating section (24) and an outlet section (25), wherein the inlet section (21), the preheating section (22), the evaporation section (23), the superheating section (24) and the outlet section (25) are connected in sequence, wherein the inlet section (21) is used for the heat exchange fluid to be exchanged to enter the heat exchange channel (2), and the preheating section (22) is used for preheating the fluid flowing through the section so that the fluid absorbs heat. and converting it into a gas-liquid two-phase fluid, the evaporation section (23) being used to completely evaporate the fluid flowing through this section, the superheating section (24) being used to allow the completely evaporated fluid to continue to absorb heat, the outlet section (25) being used to allow the fluid to flow out of the heat exchange channel (2) after the heat exchange is completed, the evaporation section (23) comprising a first separation section (231) and a second evaporation section (232), the first separation section (231) and the second evaporation section (232) being connected in sequence, the first separation section (231) being used to separate the gas-liquid of the fluid flowing through, and the second evaporation section (232) being used to completely evaporate the liquid phase fluid after the gas-liquid separation; An overflow weir (2311) and a sieve hole (2312) are provided in the first separation section (231); the sieve hole (2312) is provided after the overflow weir (2311) in the first separation section (231); a plurality of the sieve holes (2312) are provided; the overflow weir (2311) is connected to the inner wall of the heat exchange channel (2) and protrudes from the inner wall of the heat exchange channel (2); the overflow weir (2311) is used to intercept and store unevaporated liquid phase fluid; the sieve hole (2312) is provided on the side wall of the heat exchange channel (2) and can connect two adjacent heat exchange channels (2); the sieve hole (2312) is used for the evaporated gas phase fluid to pass through by relying on buoyancy and to be concentrated in the upper channel at the first separation section (231), thereby achieving gas-liquid phase separation; The overflow weir (2311) extends in the opposite direction of the gravity direction at the first separation section (231); The overflow weir (2311) can reduce the cross-sectional area of ​​the location where it is set by 1 / 3-2 / 3; The axis of the sieve hole (2312) coincides with the direction of gravity applied to the first separation section (231); The second evaporation section (232) comprises a gas phase channel (2321) and a liquid phase channel (2322), the gas phase channel (2321) and the liquid phase channel (2322) being arranged in parallel, the gas phase channel (2321) being connected to the upper channel of the first separation section (231), the liquid phase channel (2322) being connected to the lower channel of the first separation section (231), the cross-sectional area of ​​the gas phase channel (2321) being greater than the cross-sectional area of ​​the liquid phase channel (2322), a plurality of liquid phase channels (2322) being arranged in parallel, and being connected to the lower channel of the same first separation section (231); The number of superheating channels (241) provided at the superheating section (24) is three times the number of heat exchange channels (2) at the preheating section (23).

2. The microchannel heat exchange panel suitable for phase change heat exchange according to claim 1, characterized in that: There are two liquid phase channels (2322) arranged in parallel.

3. The microchannel heat exchange panel suitable for phase change heat exchange according to claim 2, characterized in that: The cross-sectional area of ​​the overheating channel (241) provided at the overheating section (24) is smaller than the cross-sectional area of ​​the channel at the preheating section (22).

4. The microchannel heat exchange panel suitable for phase change heat exchange according to claim 3, characterized in that: The gas phase channel (2321) is in communication with a plurality of superheating channels (241).

5. A heat exchanger, characterized in that: The heat exchanger comprises a microchannel heat exchange panel suitable for phase change heat exchange as described in any one of claims 1 to 4.

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