TWI881815B - Condensing units and two-phase immersion cooling systems - Google Patents

Abstract

A condensing device and a two-phase immersion cooling system including the condensing device, the condensing device includes two base units and a condensing unit. Each base unit includes a stand and a plurality of limit rods arranged on the stand, each limit rod has a plurality of openings and at least one inner hole connected to the openings, and two of the limit rods arranged opposite to each other are defined as a limit rod group. The condensing unit includes a plurality of condensing tube groups respectively connected to the limit rod groups, and a plurality of connecting tubes connected to the condensing tube groups. The diameter of the outer condensing tubes of each condensing tube group is substantially the same as the diameter of the inner condensing tube, and the center distance between each outer condensing tube and the inner condensing tube is less than twice the diameter of the inner condensing tube, so as to improve the compactness of each condensing tube group, thereby improving the condensing effect of each condensing tube group.

Description

Condensing units and two-phase immersion cooling systems

The present invention relates to a condensing device, and more particularly to a condensing device and a two-phase immersion cooling system used in a two-phase immersion cooling system.

Referring to FIG. 1 and FIG. 2 , a conventional condensing device 1 includes nine condensing tubes 11 spaced apart from each other, and eight connecting elbows 12. Each condensing tube 11 has a front end 111 and a rear end 112 disposed opposite to each other. Four of the connecting elbows 12 are respectively fixed to two of the front ends 111, and the other four of the connecting elbows 12 are respectively fixed to two of the rear ends 112, so as to define a cooling pipeline for refrigerant to flow through the condensing tubes 11 and the connecting elbows 12, thereby generating a condensation effect.

However, the connecting bends 12 are mostly made of copper tubes by bending according to the existing process, and the center distance between the two sides is related to the tube diameter of the connecting bends 12. In order to reduce the risk of bending and cracking, the center distance of each connecting bend 12 must be greater than 2.2 times the tube diameter of each connecting bend 12 (t1＜2.2×t2), that is, the center distance of the two adjacent condensing tubes 11 must be greater than 2.2 times the tube diameter of the two condensing tubes 11 (t1＜2.2×t2).

In other words, if the center distance between the condensing tubes 11 can be shortened, the compactness of the condensing tubes 11 per unit volume can be increased, thereby improving the condensation effect.

Therefore, an object of the present invention is to provide a condensing device capable of improving cooling efficiency and a two-phase immersion cooling system comprising the condensing device.

Therefore, the condensing device of the present invention comprises two base units and a condensing unit. Each base unit comprises a stand and a plurality of limit rods arranged on the stand at intervals along a vertical direction. Each limit rod extends along a front-back direction and has a plurality of openings and at least one inner hole connecting the openings. Two of the limit rods arranged opposite to each other along a left-right direction are defined as a limit rod set. The condensation unit includes a plurality of condensation tube groups respectively connected to the limit rod groups and arranged at intervals along the up-down direction, and a plurality of connecting tubes connected to the condensation tube groups. Each condensation tube group extends along the left-right direction and is connected to the openings of the respective limit rod groups. Each condensation tube group has two outer condensation tubes and at least one inner condensation tube located between the outer condensation tubes along the front-back direction. Each outer condensation tube is connected to the inner hole of one of the limit rods, and each inner condensation tube is connected to the respective limit rods. The inner holes of the limit rods of the position rod group, each connecting tube is arranged between two of the condenser tube groups, and is fixedly connected between two adjacent ones of the outer condenser tubes of the two condenser tube groups, so that the condenser tube groups and the connecting tubes together constitute a cooling pipeline, the tube diameter of the outer condenser tubes of each condenser tube group is substantially the same as the tube diameter of the inner condenser tube, and the center distance between one of the outer condenser tubes and the inner condenser tube of each condenser tube group is less than twice the tube diameter of the inner condenser tube.

Therefore, the two-phase immersion cooling system of the present invention comprises an outer shell, an electronic device and the condensing device. The outer shell defines a lower space for containing a non-conductive cooling liquid, and an upper space connected to the lower space and located above the lower space in a vertical direction. The electronic device is located in the lower space and is used to be immersed in the non-conductive cooling liquid. The condensing device is fixed to the outer shell and located in the upper space.

The effect of the present invention is that by setting the limit rod groups of the base units and connecting each condenser tube group to the openings of the respective limit rod groups, the center distance between one of the outer condenser tubes and the inner condenser tube of each condenser tube group can be less than twice the diameter of the inner condenser tube, thereby improving the compactness of each condenser tube group.

Before the present invention is described in detail, it should be noted that similar components are represented by the same reference numerals in the following description.

Referring to FIG. 3 , an embodiment of the two-phase immersion cooling system of the present invention includes a housing 2 , an electronic device 3 and a condensing device 4 .

The housing 2 defines a lower space 21 for containing a non-conductive cooling liquid (not shown), and an upper space 22 connected to the lower space 21 and located above the lower space 21 along a vertical direction D1. In this embodiment, the non-conductive cooling liquid is a fluorinated liquid.

The electronic device 3 is located in the lower space 21 and is used to be immersed in the non-conductive cooling liquid. In this embodiment, the electronic device 3 is a circuit board with a high-performance computing chip.

4 and 5 , the condensing device 4 includes two base units 5 and a condensing unit 6 .

Each base unit 5 includes a stand 51, five limit rods 52 spaced apart on the stand 51 along the up-down direction D1, and a reinforcement frame 53 connected to the stand 51 and used to be installed on the inner side of the housing 2. The stand 51 and the reinforcement frames 53 are made of stainless steel to enhance the locking force and support force of the condensing unit 6 when installed and applied to the housing 2.

Each stand 51 defines a hollow area 511 and has an inner annular surface 512 surrounding the hollow area 511. The inner annular surface 512 has a first inner side surface 513 with a sawtooth shape, a second inner side surface 514 extending along the up-down direction D1, and two connecting inner side surfaces 515 connected between the first inner side surface 513 and the second inner side surface 514 and extending along a front-to-back direction D2.

Two of the limit rods 52 that are disposed opposite to each other along a left-right direction D3 are defined as a limit rod set 520. In other words, the base units 5 together define five limit rod sets 520. However, in other variations, the number of the limit rod sets 520 can be adjusted accordingly as required.

Referring to FIG. 6 and FIG. 7 , each limit rod 52 extends along the front-rear direction D2. In the present embodiment, each limit rod 52 has four openings 521 and two inner holes 522. Each inner hole 522 is connected to two of the openings 521, and the number of the inner holes 522 is twice the number of the openings 521. In the present embodiment, the limit rods 52 are rectangular long rods processed with the openings 521 and the inner holes 522, and the material used for the limit rods 52 is red copper, oxygen-free copper, or other copper-based metals with similar thermal conductivity.

Referring to FIGS. 6 to 8 , the condensing unit 6 includes five condensing tube groups 61 respectively connected to the limit rod groups 520 and arranged at intervals along the up-down direction D1, four connecting tubes 62 connected to the condensing tube groups 61, and a medium inlet 63 and a medium outlet 64 connected to the condensing tube groups 61. The materials used for the condensing tube groups 61 and the connecting tubes 62 are red copper, oxygen-free copper, or other copper-based metals with similar thermal conductivity. The medium inlet 63 is used for the refrigerant (not shown) to enter the condensing tube groups 61, and the medium outlet 64 is used for the refrigerant to be discharged from the outer shell 2 after absorbing heat. In other variations, the number of the condensing tube groups 61 can be adjusted accordingly according to demand.

Each condenser tube set 61 extends along the left-right direction D3 and is connected to the openings 521 of the respective limit rod set 520. Each condenser tube set 61 has two outer condensers 611 and three inner condensers 612 located between the outer condensers 611 along the front-back direction D2. Each outer condenser tube 611 is connected to one inner hole 522 of one limit rod 52 of the respective limit rod set 520, and each inner condenser tube 612 is connected to two inner holes 522 of the limit rods 52 of the respective limit rod set 520. Two adjacent ones of the condenser tube sets 61 are arranged to be staggered in their projections along the up-down direction D1.

Referring to FIG. 8 , the diameter of the outer condenser tubes 611 of each condenser tube group 61 is substantially the same as the diameter of the inner condenser tubes 612. The center distance between one of the outer condenser tubes 611 of each condenser tube group 61 and the adjacent inner condenser tube 612 is less than twice the diameter of the inner condenser tube 612 (t3＜2×t4), thereby improving the compactness of each condenser tube group 61.

In addition, the center distance between one of the outer condenser tubes 611 of each condenser tube group 61 and the adjacent inner condenser tube 612 is greater than a distance threshold, and the distance threshold is the sum of the tube diameter of the inner condenser tube 612 and a buffer distance (t3＞t4+buffer distance), and the buffer distance is between 7 mm and 9 mm, so that the condenser tube groups 61 can be fixed to the limit rods 52 by copper-silver gas welding.

For example, if a condenser tube with a diameter of 1/2 inch (12.7 mm) is used, the center distance between the two adjacent condensers 11 in the existing condenser device 1 is greater than 27.9 mm. In this embodiment, the center distance between one of the outer condensers 611 and the adjacent inner condenser tube 612 of each condenser tube assembly 61 is between 19.7 mm and 25.4 mm, that is, the center distance of this embodiment can be shortened to 70% of the center distance of the existing condenser device 1 (19.7/27.9≈70%), thereby improving the compactness of each condenser tube assembly 61 per unit volume.

In each condenser tube set 61, each inner condenser tube 612 is connected to one inner hole 522 of one base unit 5 and one inner hole 522 of the other base unit 5, so that each condenser tube set 61 and the corresponding four of the inner holes 522 form an S-shaped curved pipeline, and the number of the curved pipelines is the same as the number of the limit rods 52 of each base unit 5. Each connecting tube 62 is arranged between two condenser tube sets 61, and is fixedly connected to two of the outer condenser tubes 611 of the two condenser tube sets 61 that are adjacent along the up-down direction D1, and is adjacent to one of the frames 51 along the left-right direction D3, so that the condenser tube sets 61 and the connecting tubes 62 (the curved pipelines) together form a cooling pipeline. The outer condenser tube 611 at the front of the bottom condenser tube group 61 along the front-to-rear direction D2 defines the medium inlet 63 connected to the cooling pipeline, and the outer condenser tube 611 at the back of the top condenser tube group 61 along the front-to-rear direction D2 defines the medium outlet 64 connected to the cooling pipeline.

For example, the outer condenser tube 611 at the front of the top condenser tube set 61 in FIG8 along the front-rear direction D2 is connected to the second condenser tube set 61 from the top through the corresponding connecting tube 62 (which does not exist when viewed from the direction indicated by the section line in FIG6 , so it is drawn with an imaginary line). Then, the outer condenser tube 611 at the rear of the second condenser tube set 61 from the top along the front-rear direction D2 is connected to the third condenser tube set 61 from the top through the corresponding connecting tube 62, and so on.

It is worth mentioning that the number of the inner condenser tubes 612 of each condenser tube group 61 can be adjusted according to the length limit of the upper space 22 along the front-to-back direction D2, and the number of the openings 521 and the inner holes 522 of each limit rod 52 also need to be adjusted accordingly. For example, the number of the inner condenser tubes 612 of each condenser tube group 61 can be but not limited to 1, 5, 7, or 9. The number of the openings 521 of each limit rod 52 is the number of the inner condenser tubes 612 of each condenser tube group 61 plus one, that is, it can be but not limited to 2, 6, 8, or 10. The number of the inner holes 522 of each limit rod 52 is the number of the openings 521 of each limit rod 52 divided by two, that is, it can be but not limited to 1, 3, 4, or 5.

Two of the connecting tubes 62 define a first extension direction D4, and the other two of the connecting tubes 62 define a second extension direction D5. The first extension direction D4 and the front-rear direction D2 together define an acute angle θ1, and the acute angle θ1 is between 50 degrees and 70 degrees. Since the first extension direction D4 and the second extension direction D5 are mirror images relative to the up-down direction D1, the second extension direction D5 and the front-rear direction D2 also define the acute angle θ1 together.

In actual use, referring to FIG. 3 , since the non-conductive coolant has a low boiling point, it is easy for the non-conductive coolant to evaporate into a gaseous state after absorbing the heat of the electronic device 3 and condense and fall after contacting the condensation tube assembly 61 , transferring the heat of the electronic device 3 to the refrigerant and discharging it out of the housing 2 , thereby cooling and lowering the temperature of the electronic device 3 .

Referring to FIG. 9 , FIG. 9 is a variation of the two-phase immersion cooling system of the present invention, in which the housing 2 and the electronic device 3 are omitted to present the features of the variation in a concise manner. The difference between the variation and the embodiment is that the variation includes two condensing devices 4, the medium inlets 63 of the condensing devices 4 are used together to allow the refrigerant (not shown) to enter the condensing tube assemblies 61, and the medium outlets 64 are used together to allow the refrigerant after absorbing heat to be discharged from the housing 2, so as to cool and reduce the temperature of the electronic device 3 (as shown in FIG. 3 ). The number of the condensing devices 4 can also be adjusted accordingly according to demand, and is not limited to the variation.

Therefore, the embodiment and the variation of the two-phase immersion cooling system of the present invention have the following effects:

(i) By providing the limiting rod assemblies 520 of the base units 5 and connecting each condensing tube assembly 61 to the openings 521 of the limiting rod assemblies 520, the center distance between one of the outer condensing tubes 611 and the inner condensing tube 612 of each condensing tube assembly 61 can be less than twice the diameter of the inner condensing tube 612, thereby improving the compactness of each condensing tube assembly 61 under the unit volume. In this way, the condensing effect can be further improved.

(ii) By making the center distance between one of the outer condenser tubes 611 of each condenser tube assembly 61 and the adjacent inner condenser tube 612 greater than the distance threshold, the evaporated non-conductive cooling liquid can flow between each outer condenser tube 611 and the adjacent inner condenser tube 612, so that the condenser tube assemblies 61 can be fixedly connected to the limit rods 52 by copper-silver gas welding.

(iii) By arranging two adjacent ones of the condenser tube groups 61 in a staggered manner along the projections of the up-down direction D1, the contact area between the outer condenser tubes 611 and the inner condenser tubes 612 is increased, and the non-conductive cooling liquid after evaporation is prevented from being blocked when it condenses into liquid and drips in the outer condenser tubes 611 and the inner condenser tubes 612, thereby jointly improving the cooling efficiency.

(iv) By making the first inner side surfaces 513 of the stands 51 shrink in a sawtooth shape, the proportion of the hollow areas 511 is increased, so that the evaporated non-conductive cooling liquid can pass through the stands 51 along the left-right direction D3, thereby increasing the probability of contacting the condensation tube assemblies 61.

In summary, the structures of the condensing device and the two-phase immersion cooling system of the present invention can improve the overall compactness and can indeed achieve the purpose of the present invention.

However, the above is only an embodiment of the present invention and should not be used to limit the scope of implementation of the present invention. All simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the content of the patent specification are still within the scope of the present patent.

2: Outer shell 21: Lower space 22: Upper space 3: Electronic device 4: Condenser 5: Base unit 51: Stand 511: Hollow area 512: Inner ring surface 513: First inner surface 514: Second inner surface 515: Connecting inner surface 52: Limit rod 520: Limit rod assembly 521: Opening 522: Inner hole 53: Reinforcement frame 6: Condenser unit 61: Condenser tube assembly 611: Outer condenser tube 612: Inner condenser tube 62: Connecting tube 63: Medium inlet 64: Medium outlet D1: Up and down direction D2: Front and back direction D3: Left and right direction D4: First extension direction D5: Second extension direction

Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, in which: Figure 1 is a three-dimensional diagram of a conventional condensing device; Figure 2 is a side view of the conventional condensing device; Figure 3 is a three-dimensional diagram of an embodiment of the two-phase immersion cooling system of the present invention; Figure 4 is a three-dimensional diagram of a condensing device of the embodiment; Figure 5 is a side view of the condensing device of the embodiment; Figure 6 is a top view of the condensing device of the embodiment; Figure 7 is an incomplete top view schematic diagram illustrating two base units and one condensing tube set of a condensing unit of the embodiment; Figure 8 is a cross-sectional view taken along line VIII-VIII of Figure 6; and FIG9 is an incomplete schematic diagram illustrating a state where a housing and an electronic device are removed from a variation of the two-phase immersion cooling system of the present invention.

4: Condensation device

5: Base unit

51: Stand

52: Limit rod

520: Limit rod assembly

53: Reinforcement frame

6: Condensation unit

61: Condenser tube assembly

611: External condenser tube

612: Internal condenser tube

62: Connecting pipe

63: Medium entrance

64: Medium outlet

D1: Up and down direction

D2: front and back direction

D3: Left and right direction

Claims (9)

A condensing device, comprising: Two base units, each base unit including a stand, and a plurality of limit rods arranged on the stand at intervals along a vertical direction, each limit rod extending along a front-rear direction, and having a plurality of openings, and at least one inner hole connecting the openings, and defining two of the limit rods arranged opposite to each other along a left-right direction as a limit rod set; and A condensation unit includes a plurality of condensation tube groups respectively connected to the limit rod groups and arranged at intervals along the up-down direction, and a plurality of connecting tubes connected to the condensation tube groups, each condensation tube group extends along the left-right direction and is connected to the openings of the respective limit rod groups, each condensation tube group has two outer condensation tubes, and at least one inner condensation tube located between the outer condensation tubes along the front-back direction, each outer condensation tube is connected to the inner hole of one of the limit rods, and each inner condensation tube is connected to the respective limit rods. The inner holes of the limit rods of the position rod group, each connecting tube is arranged between two of the condenser tube groups, and is fixedly connected between two of the adjacent outer condenser tubes of the two condenser tube groups, so that the condenser tube groups and the connecting tubes together constitute a cooling pipeline, the diameter of the outer condenser tubes of each condenser tube group is substantially the same as the diameter of the inner condenser tube, and the center distance between one of the outer condenser tubes and the inner condenser tube of each condenser tube group is less than 2 times the diameter of the inner condenser tube. A condensing device as described in claim 1, wherein the center distance between an outer condensing tube and the inner condensing tube of each condensing tube group is greater than a distance threshold, the distance threshold is the sum of the tube diameter of the inner condensing tube and a buffer distance, and the buffer distance is between 7 mm and 9 mm. A condensing device as described in claim 1, wherein each limiting rod has four openings and two inner holes, each inner hole is connected to two of the openings, and each condensing tube group has three inner condensing tubes located between the outer condensing tubes along the front-to-back direction. A condensing device as described in claim 1, wherein projections of two adjacent ones of the condensing tube groups along the up-down direction are arranged staggered with each other. A condensing device as described in claim 4, wherein each stand defines a hollow area and has an inner annular surface surrounding the hollow area, the inner annular surface having a first saw-shaped inner surface portion, a second inner surface portion extending along the up-down direction, and two connecting inner surface portions connected between the first inner surface portion and the second inner surface portion and extending along the front-to-back direction. A condensing device as described in claim 5, wherein the condensing unit includes four connecting tubes, two of the connecting tubes define a first extension direction, and the other two of the connecting tubes define a second extension direction, the first extension direction and the front-rear direction together define a sharp angle, and the second extension direction and the front-rear direction also together define the sharp angle, and the sharp angle is between 50 degrees and 70 degrees. A condensing device as described in claim 1, wherein each base unit also includes a reinforcement frame connected to the stand. A two-phase immersion cooling system, suitable for a non-conductive cooling liquid, comprises: a housing, defining a lower space for containing a non-conductive cooling liquid, and an upper space connected to the lower space and located above the lower space in a vertical direction; an electronic device, located in the lower space and used to be immersed in the non-conductive cooling liquid; and at least one condensing device as described in claim 1, fixed to the housing and located in the upper space. The two-phase immersion cooling system as described in claim 8 comprises a plurality of condensing devices as described in claim 1.