TWI580921B - Pulsating multi-pipe heat pipe - Google Patents

Description

Pulse type multi-tube heat pipe

The disclosure relates to a heat pipe for heat dissipation, in particular to a plurality of separate chambers at a plurality of serpentine metal tubes, respectively, and respectively connecting the two ends of the plurality of serpentine metal tubes to the independent ones. In the chamber, a pulse type multi-tube heat pipe that surrounds an open circuit.

Heat pipes have good heat transfer properties, so they are widely used in the heat dissipation of electronic components, especially in personal computers and notebook computers. Generally, when faced with the heat dissipation requirement in the form of planar heating, multiple heat pipes must be used in the design to meet the heat dissipation requirements. However, the use of multiple heat pipes can cause difficulties in heat dissipation design, assembly and fabrication of the heat dissipation module. Therefore, the Vapor Chamber is a suitable heat transfer element for conventional heat pipes in the face of heat dissipation requirements in the form of heat in the plane.

The difficulty of using a flat-plate heat pipe with capillary action is that the structure of the capillary action is sintered. The main reasons are as follows: 1. The larger the flat-type heat pipe is, the more difficult it is to control the uniformity of the capillary action structure, and thus it is easy to cause unstable performance; The larger the flat-plate heat pipe, the larger the sintering furnace for sintering the capillary action structure, which leads to an increase in cost and a decrease in mass production speed. 3. The flat-plate heat pipe after annealing has a greatly reduced wall strength, which may result in The wall of the pipe does not have the strength required to respond to changes in internal and external pressures. Since there is a lot of production due to the sintering of the capillary action structure The problem is that heat pipes with pulsating heat pipe or oscillating heat pipe are another option for planar heat transfer.

The overall structure of the existing pulse-type heat pipe is quite simple, and it is formed by connecting single-tube thin tubes. The driving force of the pulse type heat pipe is to cause the heat pipe to act by the capillary force generated by the smaller pipe diameter, the gravity of the working liquid, and the bubble pressure generated by the heat. However, the traditional single-tube pulse type heat pipe has a relatively limited capillary force, so the operation of the conventional pulse type heat pipe mainly uses gravity. Since the operation of the conventional pulse type heat pipe mainly relies on gravity, the heat pipe will not operate when the heat pipe is in a horizontal state or the heat receiving end is higher than the heat radiating end. The Republic of China I387718 patent, and other documents document the use of check valves, can improve the horizontal start, but can not solve the problem of negative angle start, but due to gravity, the working fluid is not easy to flow back to the evaporation section, so the pulse type The heat pipe fails, so the problem of negative angle starting cannot be solved, and the thermal resistance cannot be improved. Although the applicant's application number 102131568 has overcome the problem that the horizontal or negative angle cannot be started, it still cannot solve the problem that the low temperature cannot be started.

In order to solve the problem that the single-tube pulse type heat pipe is horizontal or the heat receiving end is higher than the heat radiating end (negative angle), or the heat pipe will not operate at a low temperature, a pulse type multi-tube heat pipe is developed to have The pulse-type heat pipe comprises: using a metal tube which is parallel to each other and bent into a plurality of serpentine tubes, and respectively disposed at two ends of the plurality of serpentine metal tubes, each of which is provided with a separate chamber, respectively, and a plurality of serpentines respectively The two ends of the metal tube are connected to the independent chamber to surround the open circuit, so that the working fluids cross each other to increase the pressure difference among the plurality of tubes, thereby improving the heat dissipation effect and successfully overcoming the traditional pulse type heat pipe. The level, negative angle and low temperature cannot be activated.

Through the connection of a plurality of metal pipes, an unbalanced volume filling amount is generated, and when the operation is performed, the filling amount will dynamically change and alternate the cross-flow action. Under the negative 90 degree operation, that is, the evaporation end is on, the condensing end can be operated in the lower operating state, and the heat transfer effect can be completed in the low temperature state. The embodiment of the invention includes a plurality of serpentine metal tubes of the same diameter, and a plurality of serpentine metal tubes of different diameters may be used, and a plurality of chambers are respectively disposed at two ends of the plurality of metal tubes, respectively The plurality of serpentine metal tubes are connected.

It is also to be understood by those of ordinary skill in the art that this invention is not limited to the spirit and scope of the disclosure disclosed in the appended claims.

1, 2, 3, 4, 5, 6, 7, 8‧‧‧ pulse type multi-tube heat pipe

11, 12, 21, 22, 31, 32, 41, 42, 43, 51, 52, 53, 61, 62, 63, 71, 72, 81, 82‧‧‧ metal pipes

13, 73, 74‧‧‧ snake-shaped circuit

14,18,24,28‧‧‧ chamber

15, 75‧‧‧heated area

16, 76, 77‧‧ ‧ Condensation zone

17‧‧‧Baffle

1 is a schematic view of a pulse type heat pipe according to a first embodiment of the present invention; FIG. 2 is a schematic view of a pulse type heat pipe according to a second embodiment of the present invention; 4 is a schematic view of a pulse type heat pipe according to a fourth embodiment of the present invention; FIG. 5 is a schematic view of a pulse type heat pipe according to a fifth embodiment of the present invention; and FIGS. 6A and 6B are schematic views of a pulse type heat pipe according to a sixth embodiment of the present disclosure; 7 is a schematic view of a pulse type heat pipe according to a seventh embodiment of the present invention; FIG. 8 is a schematic view of a pulse type heat pipe according to an eighth embodiment of the present invention; FIG. 9 is a comparison table of horizontal operation characteristics of the present disclosure; Negative 90 degree operating characteristic comparison table.

FIG. 1 discloses a first embodiment of the present invention, and discloses a pulse type multi-tube heat pipe 1 which is a heat pipe having a pulse type, comprising: two metal pipes 11 and 12 of the same pipe diameter, each metal pipe 11, One end of 12 includes a plurality of serpentine loops 13 and each surrounds an open system, and two metal tubes 11, 12 of the same diameter are parallel to each other. And using two independent chambers 14, 18 to connect the two metal tubes 11, 12 to form a pulse type heat pipe 1, wherein the two independent chambers 14, 18 are connected to a chamber using a partition 17, which will The chambers are spaced apart to form two separate chambers 14, 18 which are not in the same chamber and which can be formed into two separate chambers 14, 18 using two separate chambers. One end 15 of the pulse type heat pipe 1 is a heat receiving zone (may also be a condensation zone), and the other end 16 is a condensation zone (which may also be a heated zone), and the positions of the chambers 14, 18 are not limited to the condensation zone, and are pulse type. Other locations of the heat pipe 1, or the two metal tubes 11, 12 are coupled to different sides of the two separate chambers 14, 18, are also within the scope of this patent.

2A, 2B disclose a second embodiment of the present invention, and discloses a second pulse type multi-tube heat pipe 2. Referring to Figure 1, a first embodiment of the present invention is disclosed, except that the two independent chambers 24, 28 are respectively disposed. The two ends of the metal pipes 21, 22 are connected to the pulse type heat pipe 2, and the two independent chambers 24, 28 are not in the same chamber, and are respectively disposed at the upper ends of the metal pipes 21, 22, and the rest are the same, so Again.

FIG. 3 discloses a third embodiment of the present invention, and discloses a third pulse type multi-tube heat pipe 3. Referring to FIG. 1 , a first embodiment of the present invention is disclosed, except that two metal pipes 31 and 32 having different pipe diameters are used. The two metal tubes 31, 32 pulse type heat pipes are connected to the pulse type heat pipes 3 by using two independent chambers 14, 18, and the rest are the same, and therefore will not be described.

4 discloses a fourth embodiment of the present invention, and discloses a fourth pulse type multi-tube heat pipe 4. Referring to FIG. 2A, FIG. 2B, a second embodiment of the present invention is disclosed, except that two metal pipes 41 and 42 having different pipe diameters are used. The two separate tubes 24, 28 are respectively used to connect the two metal tubes 41, 42 pulse type heat pipes into the pulse type heat pipes 4, and the rest are the same, and therefore will not be described.

Figure 5 discloses a fifth embodiment of the present invention, revealing a fifth pulse type multi-tube heat pipe 4, please refer to FIG. 1 to disclose the first embodiment of the present invention. Except that the three types of metal tubes 51, 52, and 53 of the same diameter are used to form the pulse type heat pipe 5, the rest are the same, and therefore will not be described, but the embodiment uses It is also within the scope of this patent to have different tube diameters or to connect the three pulse-type heat pipes using two separate chambers.

6 discloses a sixth embodiment of the present invention, and discloses a sixth pulse type multi-tube heat pipe 6. Referring to FIG. 2A, FIG. 2B, a second embodiment of the present invention is disclosed, except that three metal pipes 61, 62 of the same diameter are used. 63, the pulse-type heat pipe 6 is formed, and the rest are the same, so it will not be described, but the pipe diameter is different in this embodiment, and it is also within the scope of this patent.

Figure 7 discloses a seventh embodiment of the present invention, and discloses a seventh pulse type multi-tube heat pipe 7, which is formed by two metal pipes 71, 72 of different pipe diameters, each of which has a plurality of serpentine ends The circuits 73, 74 are each surrounded by an open system, and the plurality of serpentine circuits 73, 74 are respectively at one end of the pulse type heat pipe 7, and two independent chambers 14 are respectively used at the other ends of the metal pipes 71, 72. 18, the two pulse-type heat pipes are connected to form a pulse type multi-tube heat pipe 7, wherein the metal pipes 71, 72 are respectively located at two ends of the two independent chambers 14, 18, and are not parallel to each other, and The two separate chambers 14, 18 are not in the same chamber. The middle portion 75 of the pulse type heat pipe 7 is a heat receiving zone (also a condensation zone), and the plurality of serpentine circuits 73, 74 are respectively condensed in one of the ends 76, 77 of the pulse type heat pipe 7 (may also be heated) Zone), except that the same pipe diameter is used in this embodiment, and is also within the scope of this patent.

8 discloses an eighth embodiment of the present invention, and discloses an eighth pulse type multi-tube heat pipe 8. Referring to FIG. 7, a seventh embodiment of the present invention is disclosed, except that the two independent chambers 14, 18 are respectively disposed on the metal pipe 81. The two ends of the 82 are connected into a pulse type heat pipe 8, and the two independent chambers 14, 18 are not in the same chamber, and are respectively disposed at the two ends of the metal pipes 81, 82, and are disposed at a distance, and the rest are the same. Therefore, no longer explain, but this implementation The use of the same pipe diameter is also within the scope of this patent. The working fluid in the pulse type heat pipe 1 is injected into the chambers 14 and 18, and after the working fluid is injected, the injection is sealed, and the working fluid filling rate in the pulse type heat pipe disclosed in the present disclosure is 30~ 80% by volume, the volume ratio is the percentage of the volume of the working fluid filled in the tube and the volume of the tube when the working fluid is not filled in the tube. Before the working fluid is injected, the flow channel system needs to be evacuated from the injection port, and the working fluid filling methods of the other seven embodiments are also the same.

It should be noted that the metal pipes 11 and 12 shown in FIG. 1 have double oblique lines in different directions, respectively, in order to clearly distinguish the metal pipes 11 and 12, and do not indicate that they are cross-sectional structures. Similarly, the metal of FIG. 2A to FIG. The double slashes are also used to clearly distinguish the different metal tubes.

The two independent chambers 14, 18 are connected to the metal tube, and the two pulse type heat pipes are connected to form a pulse type heat pipe, and a circular hole is formed at both ends of the two independent chambers 14, 18, The two ends of the metal tube are respectively placed into the chambers 14, 18 through the circular holes and then welded. In addition, for example, when the diameter of the metal tubes 11, 12 is D, the widths (not shown) and the heights H of the chambers 14, 18 are 2D to 10D, respectively, because there are at least two metal tubes, so the chamber 14, the width and height of at least 2D, can also use a plurality of metal tubes, but the larger the volume of the chambers 14, 18, the more difficult to control the uniformity of the capillary structure, thus easily lead to performance instability, so the chamber The width and height of 14,18 should preferably not exceed 10D, and the length L1 is 2D to 20D. Since the length of the chambers 14, 18 does not affect the configuration of the heat dissipation module, the length can be larger than the width and height. D can be 0.1 to 8.0 mm. Since the pipe diameter D is too small to be produced, it is at least 0.1 mm. If the pipe diameter D is too large, the capillary action is poor, so the pipe diameter D is preferably not more than 8.0 mm. Pulse type When the heated zone 15 of the heat pipe 1 (see Figure 1) is heated, the working fluid evaporates to increase the vapor pressure, thereby promoting the flow of the working fluid. The high temperature and high pressure working fluid will flow to the condensing zone 16 (see Figure 1), that is, the heat is sent from the hot zone 15 to the low temperature condensing zone 16 to achieve heat transfer. In this way, the pressure difference generated by the working fluid of the metal tubes 11 and 12 is greater than the pressure difference of the single tube. Please refer to the metal tube 21 communicating with the independent chamber 24 in FIG. 2A. The working fluid generates a pressure greater than that of the working fluid of the metal tube 22. The pressure causes the working fluid in the leftmost metal pipe 21 to flow upward, and the working fluid in the leftmost metal pipe 22 flows downward, and the working fluid flow direction in the plurality of serpentine metal pipes 22 is indicated by the direction of the arrow. Referring to FIG. 2B, the working pressure of the working fluid of the metal pipe 21 communicating with the independent chamber 24 is less than the pressure generated by the working fluid of the metal pipe 22, so that the working fluid located in the leftmost metal pipe 21 flows downward, and is located at the leftmost metal. The working fluid in the tube 22 flows upward, and the working fluid flow direction in the plurality of serpentine metal tubes 22 is as indicated by the direction of the arrow, and the working fluid flow direction is opposite to that of FIG. 2A; reference is again made to the independent chamber 24 in FIG. 6A. The working pressure generated by the working fluid of the metal pipe 61 is greater than the pressure generated by the working fluid of the metal pipe 62, 63, so that the working fluid located in the leftmost metal pipe 61 flows upward. The working fluid in the leftmost metal tube 21 flows downward, and the flow direction of the working fluid in the plurality of serpentine metal tubes 62, 63 is indicated by the direction of the arrow. Referring again to the metal tube communicating with the independent chamber 24 in FIG. 6B. The pressure generated by the working fluid is less than the pressure generated by the working fluid of the metal pipe 62, 63, so that the working fluid located in the leftmost metal pipe 61 flows downward, and the working fluid located in the leftmost metal pipe 62, 63 flows upward, plural The flow direction of the working fluid in the serpentine metal tubes 62, 63 is indicated by the direction of the arrow, and the working fluid flow direction is opposite to that of FIG. 6A, so that the working fluids in the pulse type multi-tubular heat pipes 1 to 8 cross flow, so that the fluid Random distribution, forming a non-uniform filling amount, resulting in unevenness The force of the balance successfully overcomes the problem of horizontal start of the pulse type heat pipe. And it can operate in the negative 90 degree state (the evaporation end is on the upper side and the condensation end is on the bottom), so that it lacks gravity to assist the working fluid to return to the evaporation end, and can also be actuated. The communication modes of the remaining seven embodiments and the principle of cross flow of the working fluid are also the same.

[Experimental example]

In the experimental example, a closed pulse type multi-tube heat pipe and a disclosed open pulse type multi-tube heat pipe are respectively fabricated by the structure of the embodiment of FIG. 1. The pulse type multi-tube heat pipe is first evacuated, and then filled with a working fluid of about 60% of the total flow channel system volume. Then, the pulse type multi-tube heat pipe is respectively applied with different heat (Qin), and the angle of the pulse type multi-tube heat pipe is adjusted to measure the temperature of the heat receiving end (TH) and the heat radiating end (TL), and finally borrow Calculated by the thermal resistance (Rth): R _th = ( T _H - T _L ) / Q _in , from which the formula shows that the smaller the temperature difference between the heated end (TH) and the heat dissipating end (TL), the thermal resistance (Rth) The smaller the heat Qout is taken by the condensed fluid: Qout = (m / t) x (Cp) x (Tin-Tout), where Qout is the heat taken away by the condensed fluid, (m / t) Mass flow rate (Kg/S), (Cp) is the condensed fluid specific heat (J/Kg - °C ), and (Tin-Tout) is the condensed fluid inlet and outlet temperature difference ( °C ), from which the formula shows that the larger the Qout, the pulse The efficiency of the multi-tube heat pipe is better. At each operating angle, the heat Qout taken by the condensed fluid and the temperature of the heat receiving end (TH) and the heat radiating end (TL) are measured, so that the performance of the pulse type multi-tube heat pipe can be compared. In the left and right diagrams of FIG. 9, the comparison of the horizontal operating characteristics of the applicant's application No. 102131568 and the present disclosure, wherein Qout is the heat taken away by the condensing fluid, and ΔT is the heated end (TH) and the heat radiating end (TL). The temperature difference, Tavg, h is the average temperature of the heated zone. It can be seen that the closed pulse type multi-tube heat pipe cannot be started at low temperature ( 45 °C) when the average temperature of the heated zone is Tavg, h=45 °C , but the disclosure The open-pulse multi-tube heat pipe can be started at low temperature ( 45 °C) , wherein Qout ≒ 35W, ΔT ≒ 7 ° C; in the left and right diagram of Figure 10, respectively, the applicant's application number 102131568 and the negative 90 of the disclosure According to the comparison of the operating characteristics, it can be seen that the closed pulse type multi-tube heat pipe cannot be started at low temperature ( 45 °C) , but the open pulse type multi-tube heat pipe disclosed in the present invention can be started at a low temperature ( 45 ° C) , wherein Qout ≒ 28 W, △ T ≒ 4 ° C.

In summary, the pulsed heat pipe disclosed in the present invention generates an unbalanced volume filling amount by means of multi-tube communication, and when it is actuated, the filling working fluid will dynamically change and alternate in the metal pipe body. The unbalanced state of the force for a long time makes the pulsed heat pipe of the present invention can be activated at a horizontal and negative angle of 90 degrees (the evaporation end is on the upper side and the condensation end is on the lower side) and the low temperature can be activated to complete the heat transfer effect.

The technical content and technical features of the present disclosure have been disclosed as above, and those skilled in the art can still make various substitutions and modifications without departing from the spirit and scope of the disclosure. Therefore, the scope of the present disclosure is not to be construed as being limited by the scope of

1‧‧‧Pulse type multi-tube heat pipe

11, 12 ‧ ‧ metal tube

13‧‧‧Snake loop

14, 18‧‧ ‧ chamber

15‧‧‧heated area

16‧‧‧Condensation zone

17‧‧‧Baffle

Claims (20)

A pulse type multi-tube heat pipe comprising: at least two independent metal tubes each having a plurality of serpentine loops and parallel to each other; and at least two independent chambers communicating with two ends of at least two metal tubes to form a kind Pulse type multi-tube heat pipe. The pulse type multi-tube heat pipe according to claim 1, wherein the at least two metal pipes have the same pipe diameter. The pulse type multi-tube heat pipe according to claim 1, wherein the at least two metal pipes have different pipe diameters. The pulse type multi-tube heat pipe according to claim 1, wherein the at least two metal pipes have a diameter of 0.1 to 8.0 mm. The pulse type multi-tube heat pipe according to claim 1, wherein the two independent chambers are not in the same chamber, and the width and height are 2D to 10D, and the length is 2D to 20D, and D is the metal. Pipe diameter. The pulse type multi-tube heat pipe according to claim 1, wherein the two independent chambers are formed in a chamber using a partition to form two independent chambers. The pulse type multi-tube heat pipe according to claim 1, wherein the two independent chambers are not in the same chamber, and are respectively disposed at upper ends of the two independent metal tubes. The pulse type multi-tube heat pipe according to claim 1, wherein the at least two metal pipes are filled with a working fluid, and when the working fluid is heated, it can be operated at a horizontal, negative 90 degree or low temperature state. The pulse type multi-tube heat pipe according to claim 1, wherein the at least The working fluid filling rate in the two metal tubes is 30 to 80% (volume ratio). The pulse type multi-tube heat pipe according to claim 1, wherein one of the at least two metal pipes is a heated zone and the other end is a condensation zone. A pulse type multi-tube heat pipe comprises: at least two metal pipes each having a plurality of serpentine loops; at least two independent chambers communicating with two ends of at least two metal tubes to form a pulse type multi-tube heat pipe Where the metal tubes are respectively located at the ends of the chamber, not parallel to each other. The pulse type multi-tube heat pipe according to claim 11, wherein the at least two metal pipes have the same pipe diameter. The pulse type multi-tube heat pipe according to claim 11, wherein the at least two metal pipes have different pipe diameters. The pulse type multi-tube heat pipe according to claim 11, wherein the at least two metal pipes have a diameter of 0.1 to 8.0 mm. The pulse type multi-tube heat pipe according to claim 11, wherein the independent chamber is not in the same chamber, and the width and height of the chamber are 2D to 10D, and the length is 2D to 20D, and D is the The diameter of the metal pipe. The pulse type multi-tube heat pipe according to claim 11, wherein the two independent chambers are formed in a chamber using a partition to form two independent chambers. The pulse type multi-tube heat pipe according to claim 11, wherein the two independent chambers are not in the same chamber, and are respectively disposed at upper ends of the two independent metal tubes. The pulse type multi-tube heat pipe according to claim 11, wherein the at least two metal pipes are filled with a working fluid, and when the working fluid is heated, it is horizontal. Operate at minus 90 degrees or at low temperatures. The pulse type multi-tubular heat pipe according to claim 11, wherein the working fluid filling rate in the at least two metal pipes is 30 to 80% by volume. The pulse type multi-tube heat pipe according to claim 11, wherein the middle of the at least two metal pipes is a heated zone, and the other ends are respectively a condensation zone.