Jet boiling pump-free cooling system combined with sintering pin-fin structure

Abstract

The invention discloses a jet flow boiling pump-free cooling system combined with a sintering pin-fin structure, which comprises a jet flow boiling heat exchange chamber, a steam pipeline, a liquid storage device, a condenser and a circulation loop formed by a condensation pipeline, the jet flow boiling heat exchange chamber is a closed cavity, the first side wall of the jet flow boiling heat exchange chamber is a heat source substrate, the second side wall of the jet flow boiling heat exchange chamber is a condensation pipe connecting wall, and the jet flow boiling heat exchange chamber and the condensation pipe connecting wall are opposite. A jet flow hole plate is arranged between the heat source substrate and the condenser pipe connecting wall, and sintering needle fins are arranged on the inner side of the heat source substrate. An exhaust hole is formed in the top of a cavity formed by the heat source substrate and the jet flow hole plate and connected with a steam pipeline. The condensation pipe connecting wall is provided with a through hole connected with a condensation pipeline. The liquid storage device is higher than the jet flow boiling heat exchange chamber, the steam pipeline and the condensation pipeline are both connected with the liquid storage device, the liquid storage device is connected with a condenser used for condensing heat dissipation working media, and the heat dissipation working media are arranged in the circulation loop. Pump-free circulation is adopted, energy is saved, and the heat dissipation capacity is high.

Description

Technical Field

[0001] The invention relates to a jet boiling cooling system, belonging to the technical field of heat exchange devices. Background Art

[0002] With the improvement of chip integration, when electronic devices exceed their rated operating temperature, the failure rate of electronic devices increases exponentially as the temperature increases. How to effectively dissipate heat for highly integrated power devices is a research difficulty in today's thermal design industry.

[0003] Flow boiling in traditional parallel microchannels can easily cause serious backflow problems due to steam blocking the channels at high heat flux, thus limiting its application and requiring the search for new structural forms. A Chinese patent with publication number CN102271485A discloses a method of coupled heat exchange of array jets and boiling cooling under high heat flux density conditions, in which the cooling fluid performs boiling heat exchange on the surface of a grooved reinforced structure through a dense array of jet holes to cool the target electronic components. Its circulation system needs to be driven by a liquid working fluid pump. Some pumpless circulation systems usually rely on the gravity difference between hot and cold fluids for circulation, but the circulation rate is low, so the heat dissipation capacity is limited. Summary of the invention

[0004] In view of the above-mentioned defects of the prior art, the task of the present invention is to provide a jet boiling pumpless cooling system combined with a sintered pin-fin structure, with the aim of increasing the circulation rate of the pumpless cooling system and enhancing the heat dissipation capacity.

[0005] The technical solution of the present invention is as follows: A jet boiling pumpless cooling system combined with a sintered pin-fin structure comprises a jet boiling heat exchange chamber, a steam pipeline, a liquid reservoir, a condenser and a circulation loop composed of a condensation pipeline, wherein the jet boiling heat exchange chamber is a closed cavity, the first side wall of the jet boiling heat exchange chamber is a heat source substrate, the second side wall of the jet boiling heat exchange chamber is a condensation tube connecting wall, the first side wall and the second side wall are a set of opposite wall surfaces, a jet orifice plate is arranged between the heat source substrate and the condensation tube connecting wall, sintered pin fins are arranged on the inner side of the heat source substrate, an exhaust hole is arranged on the top of the chamber formed between the heat source substrate and the jet orifice plate, the exhaust hole is connected to the steam pipeline, the condensation tube connecting wall is provided with a through hole for connecting to the condensation pipeline, the setting height of the liquid reservoir is higher than the jet boiling heat exchange chamber, the steam pipeline and the condensation pipeline are both connected to the liquid reservoir, the liquid reservoir is connected with a condenser for condensing a heat dissipation medium, and a heat dissipation medium is arranged in the circulation loop.

[0006] Furthermore, the sintered needle fin is a cylindrical structure with a diameter of 1.2 to 1.5 mm and a height of 1 to 1.3 mm.

[0007] Furthermore, the spacing between the sintered needle fins is 2 to 2.5 mm.

[0008] Furthermore, the axis of the sintered pin fin is arranged along the horizontal direction.

[0009] Furthermore, the distance between the head end of the sintered needle fin and the jet orifice plate is 0.5-1 mm. Too small a spacing is prone to produce large bubbles and cause blockage, affecting the discharge of vapor and liquid, resulting in premature occurrence of critical heat flux density CHF. Too large a spacing causes the jet velocity to be too low when it reaches the heat exchange surface, resulting in poor heat exchange effect.

[0010] Furthermore, a capillary core layer is provided on the inner side of the heat source substrate, the sintered needle fins are arranged on the surface of the capillary core layer, and the thickness of the capillary core layer is 0.15-0.3 mm.

[0011] Furthermore, the sintered needle fin is made by sintering copper powder.

[0012] Furthermore, the heat dissipation medium is Freon or deionized water.

[0013] Furthermore, the condenser is provided with a forced convection fan.

[0014] Furthermore, the condenser comprises an upper chamber and a lower chamber, the upper chamber and the lower chamber are connected via a plurality of condensing tubes, and the lower chamber is in communication with the liquid reservoir.

[0015] The advantages of the present invention compared with the prior art are: The impact jet boiling is combined with the sintered needle-fin structure, and a vertically arranged jet orifice plate is used for lateral jet so that the vapor phase working medium can be discharged smoothly after boiling. The addition of the sintered needle-fin structure can greatly increase the density of the vaporization core on the one hand, and on the other hand, through the action of capillary force, the liquid working medium can be replenished to the heating surface in time to avoid the premature occurrence of drying. Thereby greatly improving the critical heat flux density CHF limit. Each needle fin replenishes the liquid working medium under the action of its capillary force, and the liquid working medium will sink under the action of gravity, while the bubbles will be generated first at the top of the needle fin and discharged directly, that is, the vapor phase working medium will move upward into the steam pipeline under the action of buoyancy, and the effect of vapor-liquid separation will be better. The liquid working medium flows and circulates under the dual action of gravity and temperature difference to ensure the timely replenishment of the liquid. The setting of the needle fins ensures sufficient circulation power. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of a jet boiling pumpless cooling system combined with a sintered pin-fin structure according to an embodiment.

[0017] Figure 2 Schematic diagram of the internal structure of the jet boiling heat exchange chamber.

[0018] Figure 3 Schematic diagram of the jet orifice plate structure.

[0019] Figure 4 Schematic diagram of the condenser and liquid receiver structure. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the embodiments, but are not intended to limit the present invention.

[0021] Please combine Figures 1 to 4 As shown, the jet boiling pumpless cooling system combined with the sintered pin-fin structure of this embodiment includes a circulation loop composed of a jet boiling heat exchange chamber 1, a steam pipeline 2, a liquid storage tank 3, a condenser 4 and a condensation pipeline 5.

[0022] The jet boiling heat exchange chamber 1 is a closed cavity for installing a heat source and dissipating the heat source. In this embodiment, the jet boiling heat exchange chamber 1 is a rectangular chamber, and its left and right side walls serve as a set of opposite wall surfaces. The left side wall is called the first side wall, and the opposite right side wall is called the second side wall.

[0023] The first side wall is a heat source substrate 101, and the heat source 6 is attached to the outside of the heat source substrate 101. The heat of the heat source 6 is transferred to the jet boiling heat exchange chamber 1 through the heat source substrate 101. The second side wall 102 is a condenser pipe connecting wall, and a through hole is provided on the wall surface for connecting with the condenser pipe 5.

[0024] A vertical jet orifice plate 103 is provided in the jet boiling heat exchange chamber 1, and the jet orifice plate 103 divides the jet boiling heat exchange chamber 1 into two left and right chambers. The heat source substrate 101 is in the left chamber, and the condensation pipeline 5 is connected to the right chamber. The jet orifice plate 103 is provided with jet holes 103a distributed in a matrix. The jet orifice plate 103 is arranged closer to the heat source substrate 101.

[0025] A sintered capillary core layer 104 is provided on the inner side of the heat source substrate 101, and a sintered needle fin 105 is provided on the surface of the capillary core layer 104. In specific implementation, the capillary core layer 104 and the sintered needle fin 105 are made of copper powder by pressure sintering. After sintering, the copper powder needs to be strictly cleaned to remove the oxide layer. The thickness of the capillary core layer 104 can be 0.15-0.3 mm, and the sintered needle fin 105 is a cylindrical structure distributed in a matrix, and the axis of the cylinder is horizontal. The diameter of each sintered needle fin 105 is 1.2-1.5 mm, the height is 1-1.3 mm, and the spacing between the sintered needle fins 105 is 2-2.5 mm. In this embodiment, the thickness of the capillary core layer 104 is 0.2 mm, the diameter of the sintered needle fin 105 is 1.5 mm, the height is 1.3 mm, and the spacing between the sintered needle fins 105 is 2.5 mm. The distance between the jet orifice plate 103 and the top of the sintered pin fin 105 is controlled to be 0.5-1 mm. Too small a distance is prone to produce large bubbles and cause blockage, affecting the discharge of vapor and liquid, resulting in premature occurrence of critical heat flux density CHF. Too large a distance will cause the jet velocity to be too low when it reaches the heat exchange surface, resulting in poor heat exchange effect. In this embodiment, it is 0.5 mm.

[0026] The top of the chamber on the left side of the jet boiling heat exchange chamber 1 is a transition chamber 106. The bottom of the transition chamber 106 is connected to the left chamber of the jet boiling heat exchange chamber 1 through a rectangular notch 106b. An exhaust hole 106a is provided on the top of the transition chamber 106 for connecting with the steam pipeline 2. A layer of thermal insulation material 7 can also be provided outside the jet boiling heat exchange chamber 1.

[0027] The liquid reservoir 3 is arranged at a position higher than the jet boiling heat exchange chamber 1. The top end of the steam pipeline 2 is connected to the liquid reservoir 3 and extends from the left side of the bottom of the liquid reservoir 3, and the top end of the condensation pipeline 5 is connected to the right side of the bottom of the liquid reservoir 3. The top end of the steam pipeline 2 is higher than the top end of the condensation pipeline 5.

[0028] The condenser 4 is arranged above the liquid reservoir 3, and includes an upper chamber 401 and a lower chamber 402. The upper chamber 401 and the lower chamber 402 are connected by a plurality of condensing tubes 403, and the lower chamber 402 is relatively close to the liquid reservoir 3 and is connected by a pipeline. The condenser 4 of this embodiment is provided with a forced convection fan 404, and the forced convection fan 404 generates air flow to take away the heat of the condensing tubes 403 of the condenser 4.

[0029] The circulation loop composed of the above parts is filled with heat dissipation medium, which can be Freon or deionized water. In order to ensure normal operation, strict cleaning, leak detection, pressure maintenance, vacuuming and other processes must be carried out before injecting the medium.

[0030] The heat dissipation cycle process of the jet boiling pumpless cooling system combined with the sintered needle fin structure is as follows: the liquid working medium is vertically ejected toward the heat source substrate 101 with the heat source 6 through the jet hole 103a of the jet orifice plate 103 in the jet boiling heat exchange chamber 1 due to the density difference between the steam pipeline 2 and the condensation pipeline 5, and the pressure generated by the vaporized heat dissipation working medium. The liquid working medium is heated and boiled to be transformed into a vapor working medium. Under the action of buoyancy, it enters the steam pipeline 2 from the jet boiling heat exchange chamber 1 through the exhaust hole 106a. After passing through the liquid reservoir 3, the vapor working medium dissipates heat to the external environment through forced air cooling in the condenser 4. The vapor working medium is transformed into a liquid and refluxes to the liquid reservoir 3. Then, it enters the jet boiling heat exchange chamber 1 through the condensation pipeline 5 to form a cycle.

[0031] The present invention adopts gravity-driven circulation, which has better energy-saving effect. The sintered needle-fin structure can meet the capillary liquid supply demand of the dry zone when the heat flux is high, which can greatly improve the critical heat flux density and promote the circulation of the heat dissipation medium.

Claims

1. A jet boiling pumpless cooling system combined with a sintered pin-fin structure, characterized in that: The invention relates to a circulation loop consisting of a jet boiling heat exchange chamber, a steam pipeline, a liquid reservoir, a condenser and a condensation pipeline, wherein the jet boiling heat exchange chamber is a closed cavity, the first side wall of the jet boiling heat exchange chamber is a heat source substrate, the second side wall of the jet boiling heat exchange chamber is a condensation tube connecting wall, the first side wall and the second side wall are a set of opposite wall surfaces, a jet orifice plate is provided between the heat source substrate and the condensation tube connecting wall, sintered needle fins are provided on the inner side of the heat source substrate, an exhaust hole is provided on the top of the chamber formed between the heat source substrate and the jet orifice plate, the exhaust hole is connected to the steam pipeline, the condensation tube connecting wall is provided with a through hole for connecting with the condensation pipeline, the liquid reservoir is set at a height higher than the jet boiling heat exchange chamber, the steam pipeline and the condensation pipeline are both connected to the liquid reservoir, the liquid reservoir is connected to a condenser for condensing a heat dissipation medium, and a heat dissipation medium is provided in the circulation loop.

2. The jet boiling pumpless cooling system combined with the sintered pin-fin structure according to claim 1 is characterized in that: The sintered needle fin is a cylindrical structure with a diameter of 1.2 to 1.5 mm and a height of 1 to 1.3 mm.

3. The jet boiling pumpless cooling system combined with the sintered pin-fin structure according to claim 1 or 2, characterized in that: The spacing between the sintered needle fins is 2 to 2.5 mm.

4. The jet boiling pumpless cooling system combined with the sintered pin-fin structure according to claim 1, characterized in that: The axis of the sintered pin fin is arranged along the horizontal direction.

5. The jet boiling pumpless cooling system combined with the sintered pin-fin structure according to claim 4 is characterized in that: The distance between the head end of the sintered needle fin and the jet orifice plate is 0.5-1 mm.

6. The jet boiling pumpless cooling system combined with the sintered pin-fin structure according to claim 1, characterized in that: A capillary core layer is provided on the inner side of the heat source substrate, the sintered needle fins are arranged on the surface of the capillary core layer, and the thickness of the capillary core layer is 0.15-0.3 mm.

7. The jet boiling pumpless cooling system combined with the sintered pin-fin structure according to claim 1 is characterized in that: The sintered needle fin is made by sintering copper powder.

8. The jet boiling pumpless cooling system combined with the sintered pin-fin structure according to claim 1 is characterized in that: The heat dissipation medium is Freon or deionized water.

9. The jet boiling pumpless cooling system combined with the sintered pin-fin structure according to claim 1, characterized in that: The condenser is provided with a forced convection fan.

10. The jet boiling pumpless cooling system combined with the sintered pin-fin structure according to claim 1, characterized in that: The condenser comprises an upper chamber and a lower chamber, the upper chamber and the lower chamber are connected via a plurality of condensing tubes, and the lower chamber is communicated with the liquid storage device.

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