A data center cooling apparatus

Abstract

The application discloses a data center cooling device, which comprises a two-phase heat exchanger, a two-phase pipeline, a condenser, a single-phase pipeline, a liquid supplement tank and a cooling working medium. The two-phase heat exchanger and the condenser are communicated through the two-phase pipeline and the single-phase pipeline and form a circulation loop, the circulation loop is filled with the cooling working medium, the two-phase pipeline is located above the single-phase pipeline, and the liquid supplement tank is communicated with the single-phase pipeline at an inlet end of the two-phase heat exchanger. The two-phase heat exchanger and the liquid supplement tank are located in the data center, and the condenser is arranged in a water storage pool of a waterworks above the data center. The cooling working medium is spontaneously circulated and heat transported by means of the coupling effect of the thermosyphon and gravity driving, and the data center is radiated by using the huge natural cold source of the water storage pool of the waterworks above, so that a green and zero-carbon cooling method is provided for the data center, and good social and economic benefits are achieved.

Description

Technical Field

[0001] This invention relates to the field of data center thermal management, and more particularly to a data center cooling device that uses gravity / thermal siphon coupling to drive the spontaneous circulation and heat transport of the cooling medium and utilizes the massive natural cold source of a nearby waterworks for heat dissipation. Background Technology

[0002] The massive data throughput and computation have led to a trend towards high density, integration, and high energy consumption in data centers, which serve as the "brains" of emerging technologies such as artificial intelligence and big data. Therefore, there is an urgent need to develop green, low-consumption, and efficient cooling methods to promote the realization of a "dual-carbon" strategy for data centers.

[0003] It's important to note that traditional data centers primarily rely on air cooling, using air as the refrigerant to remove heat. This necessitates a large number of air conditioners and fans, resulting in high energy consumption and significant noise pollution. Furthermore, the Power Usage Effectiveness (PUE) of traditional air-cooled data centers is only 1.5-1.8, significantly falling short of national standards. To improve data center PUE, liquid cooling technology has become the most promising development direction for green, low-power, and high-efficiency data center transformation. Indirect liquid cooling with cold plate technology has already been implemented in some data centers. Its simple structure and ability to reduce PUE to around 1.3 significantly improve the energy efficiency of data centers. Besides indirect cooling solutions, direct cooling solutions where the cooling medium directly contacts the heat source have also been developed. Typical examples include immersion liquid cooling and spray liquid cooling. Existing research shows that immersion and spray liquid cooling technologies can further reduce the data center PUE to around 1.1, thereby further reducing the power consumption for data center cooling. However, these direct liquid cooling methods are complex, difficult to maintain, and the coolant is very expensive, making large-scale application difficult. It should be noted that existing cold plate, immersion, and spray liquid cooling solutions cannot self-circulate their coolant; they still require additional power input to maintain the cooling system's operation, thus limiting the data center's power usage effect (PUE).

[0004] To address this challenge, data center cooling solutions with self-driven cooling media circulation, such as split-type heat pipe cooling, have been developed. However, current data center heat source evaporation sections suffer from limited heat transfer efficiency due to two-phase instability and insufficient heat transfer distance, hindering the further widespread application of this technology. More importantly, even if existing cooling solutions achieve self-driven cooling media circulation, heat dissipation in the condensation section still requires additional power input, failing to fundamentally achieve green, zero-carbon cooling for data centers. Therefore, the energy consumption level of data centers can be further reduced. Summary of the Invention

[0005] To address the shortcomings of existing research, this invention proposes a data center cooling device that reduces flow resistance losses to extend transport distance, significantly improves heat transfer efficiency by suppressing two-phase instability, and directly utilizes natural cooling capacity for heat dissipation without requiring additional power input.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] A data center cooling device is characterized by comprising a two-phase heat exchanger, two-phase pipes, a condenser, a single-phase pipe, a replenishment tank, and a cooling medium. The two-phase heat exchanger and the condenser are connected via the two-phase pipes and the single-phase pipe to form a sealed circulation loop. The circulation loop is filled with the cooling medium. The two-phase pipe is located above the single-phase pipe, and the replenishment tank is connected to the single-phase pipe at the inlet end of the two-phase heat exchanger. The two-phase heat exchanger and the replenishment tank are located within the data center, while the condenser is arranged in a waterworks reservoir above the data center. The two-phase heat exchanger removes the heat load of the data center through the evaporation phase change of the cooling medium. The high-temperature two-phase cooling medium is transported to the condenser in the two-phase pipe by thermosiphon and condenses and dissipates heat using the natural cooling capacity of the waterworks reservoir. The cooled single-phase cooling medium is driven by gravity to spontaneously flow back to the two-phase heat exchanger in the data center, thereby achieving passive circulation of the cooling medium.

[0008] The two-phase heat exchanger includes a base and a cover plate. A microchannel array is formed on the base. The microchannel array, along the flow direction, consists of an inlet section, a gradually expanding microchannel array, interconnected microchannels, and an outlet section. The gradually expanding microchannels are used to reduce flow resistance while suppressing steam backflow caused by explosive boiling due to excessively high local hot spots. The interconnected microchannels between the microchannel arrays are used to eliminate the pressure and flow imbalance and oscillation between channels caused by the incomplete uniformity of boiling processes and flow pattern evolution in each sub-channel by means of pressure balance effect, thereby improving the heat transfer efficiency of the two-phase heat exchanger.

[0009] The tilt angle of the gradually expanding microchannel does not exceed 10°, the hydraulic diameter does not exceed 1mm, and the cross-section of the microchannel includes, but is not limited to, rectangular, circular, and trapezoidal structures; the interconnected microchannel is located between adjacent gradually expanding microchannels, and the hydraulic diameter of the interconnected microchannel is not less than twice the hydraulic diameter of the gradually expanding microchannel.

[0010] The inner wall surface of the single-phase pipe has a gradient porosity structure, where the pore size gradually decreases along the flow direction of the cooling medium. This increases the capillary driving force of the cooling medium, achieving long-distance transport. Furthermore, the gradient porosity structure includes, but is not limited to, metal sintering pores, electrochemical deposition pores, and chemically etched pore structures.

[0011] The inner wall of the two-phase pipe is a smooth surface, and the hydraulic diameter of the two-phase pipe is larger than that of the single-phase pipe. This design helps to reduce the flow resistance loss of the two-phase cooling medium along the flow path and effectively improves the transport distance of the cooling medium.

[0012] The condensers include, but are not limited to, plate-fin, plate-strip, plate-strip, serpentine, spiral plate, and finned tube types. These condensers utilize the massive natural cooling capacity of waterworks for condensation and heat exchange, significantly improving heat exchange efficiency without requiring additional power input. Furthermore, by applying the currently underutilized massive natural cooling capacity of waterworks to address the high energy consumption problem of data center cooling, a complementary value proposition is achieved, resulting in significant social and economic benefits.

[0013] The cooling medium includes, but is not limited to, refrigerants such as methanol, ethanol, acetone, and R134a.

[0014] The materials of the two-phase heat exchanger, two-phase pipeline, condenser, single-phase pipeline and replenishment tank include, but are not limited to, aluminum, copper, steel and their alloys.

[0015] The data center cooling device based on tap water proposed in this invention has significant advantages over existing liquid cooling solutions. First, this invention utilizes the coupling effect of thermosiphon and gravity drive to achieve self-driven circulation of the cooling medium within the system. Compared to immersion, spray, and cold plate liquid cooling solutions, this invention further reduces system energy consumption, and the cooling system is simpler and more compact, facilitating later operation and maintenance, with lower overall investment costs. Moreover, this invention utilizes a single-phase pipe with a stepped pore structure to increase capillary driving force, enabling long-distance transport of the cooling medium. Furthermore, this invention employs a gradually expanding, interconnected microchannel structure in the two-phase heat exchanger at the data center heat source end, reducing flow resistance losses along the system and significantly improving heat transfer capacity by suppressing two-phase instability. More importantly, this invention utilizes the massive natural cooling capacity of the tap water plant's storage tanks for heat dissipation in the data center, greatly improving heat exchange efficiency without requiring additional power input. This provides a green, zero-carbon cooling method for data centers, further promoting the "dual-carbon" strategy for data centers. Beneficial effects

[0016] The data center cooling device proposed in this invention achieves spontaneous circulation and heat transport of the cooling medium through the coupling effect of thermosiphon and gravity drive. Simultaneously, it employs a single-phase pipe with a stepped pore structure to increase capillary driving force, thereby enabling self-driven, long-distance transport of the cooling medium within the device without additional power input. Furthermore, the use of a gradually expanding, interconnected microchannel two-phase heat exchanger suppresses the two-phase instability of boiling heat transfer, significantly improving the heat transfer efficiency at the data center's heat source. More importantly, this invention utilizes the massive, currently underutilized natural cooling capacity of waterworks to address the high energy consumption problem of data center cooling, providing a green, zero-carbon cooling method for data centers and achieving complementary value, resulting in significant social and economic benefits. Attached Figure Description

[0017] Figure 1 Schematic diagram of a water-source-based data center cooling system;

[0018] Figure 2 Schematic diagram of a two-phase heat exchanger;

[0019] Figure 3 Schematic diagram of the microchannel substrate of a two-phase heat exchanger

[0020] Figure 4 Schematic diagram of a single-phase pipeline;

[0021] Figure 5 Working principle diagram of the cooling device;

[0022] In the diagram, 1 is a two-phase heat exchanger, 2 is a heat source, 3 is a two-phase pipe, 4 is a plate-fin condenser, 5 is a single-phase pipe, 6 is a makeup tank, 7 is a data center, 8 is a waterworks reservoir, 9 is a microchannel substrate, 10 is a cover plate, 11 is an inlet section, 12 is a gradually expanding microchannel, 13 is an interconnected microchannel, 14 is an outlet section, 15 is a gradient pore structure, 16 is a two-phase cooling medium, 17 is a single-phase cooling medium, and 18 is a heat load. Implementation

[0023] The device will now be described in further detail with reference to the accompanying drawings.

[0024] Figure 1This is a schematic diagram of a water-source-based data center cooling system, including an array of two-phase heat exchangers 1, two-phase pipes 3, an array of plate-fin condensers 4, a single-phase pipe 5, and a makeup tank 6. The two-phase heat exchangers 1 and the plate-fin condensers 4 are connected by the two-phase pipes 3 and the single-phase pipes 5, forming a sealed circulation loop filled with cooling fluid. The two-phase pipes 3 are located above the single-phase pipes 5. The makeup tank 6 is connected to the single-phase pipe 5 at the inlet end of the two-phase heat exchangers 1. The two-phase heat exchangers 1 are in close contact with the heat source 2. The array of two-phase heat exchangers 1 and the makeup tank are located inside the data center 7, while the array of plate-fin condensers 4 is arranged in the water storage tank 8 of the waterworks above the data center 7.

[0025] Figure 2 and Figure 3 This is a schematic diagram of a two-phase heat exchanger and its microchannel substrate. The two-phase heat exchanger 1 mainly consists of a microchannel substrate 9 and a cover plate 10, which are welded together using techniques such as friction stir welding. A microchannel array is fabricated on the microchannel substrate 9, including an inlet section 11, a gradually expanding microchannel 12, interconnected microchannels 13, and an outlet section 14. The inclination angle of the gradually expanding microchannel 12 does not exceed 10°, and its hydraulic diameter does not exceed 1 mm. The channel cross-section includes, but is not limited to, rectangular, circular, and trapezoidal structures. This design can reduce flow resistance while suppressing steam backflow caused by explosive boiling due to excessively high local hot spots. Furthermore, interconnected microchannels 13 are formed between the microchannel arrays, and the hydraulic diameter of the interconnected microchannels 13 is not less than twice the hydraulic diameter of the gradually expanding microchannels 12. This utilizes the pressure balance effect to eliminate the pressure and flow imbalance and oscillation between channels caused by incomplete uniformity in the boiling process and flow pattern evolution of each sub-channel, thereby improving the heat transfer efficiency of the two-phase heat exchanger 1 by 10% to 20%.

[0026] Figure 4 This is a schematic diagram of a single-phase pipeline. The inner wall of the single-phase pipeline 5 is a multi-gradient pore structure 15. The pore size of the gradient pore structure 15 gradually decreases along the flow direction of the cooling medium, which can increase the capillary driving force of the cooling medium and thus realize the long-distance transport of the cooling medium.

[0027] Figure 5 The diagram illustrates the working principle of the cooling device. The two-phase heat exchanger 1 removes the heat load 18 from the heat source 2 in the data center 7 through the evaporation phase change of the cooling medium. The high-temperature two-phase cooling medium 16 is transported to the plate-fin condenser 4 in the two-phase pipe 3 by thermosiphon. The massive natural cooling capacity in the waterworks reservoir 8 cools the two-phase cooling medium 16 and removes the heat load 18. The cooled single-phase cooling medium 17 is driven by gravity in the single-phase pipe 5 to spontaneously flow back to the two-phase heat exchanger 1 in the data center 7, thereby realizing the passive circulation operation of the cooling medium.

Claims

1. A data center cooling device, characterized in that: The system includes a two-phase heat exchanger, two-phase pipes, a condenser, a single-phase pipe, a makeup liquid tank, and a cooling medium. The two-phase heat exchanger and the condenser are connected through the two-phase pipes and the single-phase pipes to form a sealed circulation loop. The circulation loop is filled with the cooling medium. The two-phase pipes are located above the single-phase pipes. The makeup liquid tank is connected to the single-phase pipe at the inlet section of the two-phase heat exchanger. The two-phase heat exchanger and the makeup liquid tank are located inside the data center. The two-phase heat exchanger removes the heat load of the data center through the evaporation phase change of the cooling medium. The high-temperature two-phase cooling medium is transported to the condenser through the two-phase pipes by thermosiphon for condensation and heat dissipation. The cooled single-phase cooling medium is driven by gravity to spontaneously flow back to the two-phase heat exchanger in the data center, thereby realizing the passive circulation operation of the cooling medium. The two-phase heat exchanger includes a microchannel array, which comprises an inlet section, a gradually expanding microchannel, interconnected microchannels, and an outlet section. The gradually expanding microchannels are used to reduce flow resistance while suppressing steam backflow caused by explosive boiling due to excessively high local hot spots. The interconnected microchannels between the microchannel arrays are used to eliminate pressure and flow imbalances and oscillations between channels caused by incomplete uniformity in the boiling process and flow pattern evolution of each sub-channel, thereby improving the heat transfer efficiency of the two-phase heat exchanger. The interconnected microchannels are interconnected channels, which are formed by arrayed protrusions. The protrusions arranged in columns form column channels on both sides of the outlet of each gradually expanding microchannel, and the protrusions arranged in rows form row channels. The column channels are connected to the row channels. The condenser is located in the water storage tank of the waterworks above the data center.

2. The data center cooling device according to claim 1, characterized in that: The two-phase heat exchanger includes a substrate and a cover plate; the microchannel array is formed on the substrate.

3. The data center cooling device according to claim 1, characterized in that: The inner wall surface of the single-phase pipe has a sintered porous structure, and the pore size of the sintered porous structure gradually decreases along the flow direction of the cooling working fluid.

4. The data center cooling device according to claim 3, characterized in that: The inner wall of the two-phase pipe has a smooth surface.

5. The data center cooling device according to claim 1, characterized in that: The cross-section of the microchannels in the microchannel array includes, but is not limited to, rectangular, circular, and trapezoidal shapes.

6. The data center cooling device according to claim 1, characterized in that: The cooling medium includes, but is not limited to, methanol, ethanol, acetone, and R134a.

7. The data center cooling device according to claim 1, characterized in that: The condenser is a plate-fin condenser.

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