CN205808199U - The pump fluid circuit microchannel cold plates of compound conduit heat pipe structure - Google Patents

Abstract

The utility model discloses a micro-channel cold plate with a compound groove heat pipe structure for a pump fluid circuit. Pipelines, outlet lines, spoiler baffles. The cross-section of the microchannel is designed in an omega shape with reference to the high-performance channel heat pipe, which can provide a certain capillary driving force while providing high heat exchange capacity. When the heating heat flow of the heat source is small, the capillary force drives the working medium to flow in the system, and the liquid working medium undergoes a phase change and overflows when heated, and flows back under the action of capillary force after condensation. When the heat flow of the heating heat source is large, the flow rate of the working medium is increased by the drive of the mechanical pump, and more liquid working medium per unit time undergoes a phase change in the cold plate, increasing the cooling capacity of the cold plate. The cold plate can be used as the evaporator in the fluid circuit driven by capillary force and mechanical pump at the same time to meet different heat exchange requirements.

Description

Microchannel cold plate with composite channel heat pipe structure for pump fluid circuit

technical field

The utility model relates to the design technology of the cold plate of the pump fluid circuit, specifically refers to the use of a microchannel heat exchanger with a compound channel heat pipe structure as the cold plate in the pump fluid circuit. The pump fluid circuit can be used for long-distance cold and heat transmission, such as cooling and heat dissipation for large-scale integrated circuits, high-power electronic devices, high-power solid-state lasers, and on-board loads.

Background technique

Fluid circuits can be mainly divided into capillary drive and mechanical pump drive according to different driving methods. The driving force provided in the two circuits is different, resulting in a difference in the thermal load that can be accommodated. The fluid circuit driven by capillary force has slow flow rate and small flow rate, which is suitable for cooling and heat dissipation under small heat load. The mechanical pump can provide a large head and driving force for the fluid circuit, and can be used for cooling and heat dissipation under a large heat load.

Common capillary force-driven fluid circuits such as capillary suction two-phase fluid circuit (CPL) and loop heat pipe (LHP). CPL was first proposed by FJ Stenger in the United States in the 1960s. In 1971, the Soviet Union proposed a heat pipe similar to LHP. , officially named LHP was proposed by Yu.F.Maidanik of the former Soviet Academy of Sciences in 1989. The evaporator of CHL often uses multi-layer coarse wire mesh to fill the liquid flow channel, and the fine wire mesh wraps solid particles to form a capillary structure and form a meniscus to provide capillary force. Porous sintered materials with smaller particle size and pore size are used in LHP, such as nickel powder and Si ₃ N ₄ ceramic liquid absorbent core, which can provide higher capillary force, but the corresponding resistance loss in the evaporator also increases.

The fluid circuit driven by the mechanical pump mainly uses various vane type and positive displacement pumps to drive the circulation of the working medium. The fluid undergoes a phase change when heated in the evaporator. After absorbing heat and vaporizing, the working fluid flows to the heat sink and then condenses, and then flows back into the evaporator under the action of the pump, continuously bringing heat from the heat source to the heat sink. The cross-section of common microchannel heat exchangers is mostly a single geometric shape such as rectangle, triangle or circle, which can provide limited capillary capacity. At the same time, when the phase change of the working medium occurs, as the gas phase fraction in the channel increases, the bubbles formed will form air plugs to block the flow of liquid when the volume of the bubbles is too large, which will deteriorate the heat transfer and cause temperature unevenness along the flow direction.

Contents of the invention

The purpose of this utility model is to propose a micro-channel cold plate that can provide a certain capillary force and maintain a large heat exchange capacity, and can be used for both capillary force-driven and mechanical pump-driven fluid circuits.

In order to achieve the above object, the design idea of the present utility model is:

1. Refer to the channel heat pipe channel structure to design a microchannel structure with low flow resistance and a certain capillary force.

2. According to the structure of the existing micro-channel heat exchanger, combined with the design of the gas and liquid flow channels of the channel heat pipe, a micro-channel heat exchanger with a steam chamber is designed to separate the gas and liquid flow channels.

According to above thinking, the present invention adopts following technical steps.

A microchannel cold plate for a pump fluid circuit, comprising: a microchannel bottom plate 11, a structural support 12, a spoiler baffle 13, a steam chamber 14, a sealing gasket 15, a heat-resistant cover plate 16, fastening bolts 17, and an inlet pipeline 18. Outlet pipeline 19. When working, the bottom mounting surface of the cold plate absorbs the heat from the heat source and transfers it to the bottom of the microchannel evenly, and the liquid working medium in the channel is heated and undergoes phase transformation into a gaseous working medium. As the gaseous working medium continues to form and leave the channel to gather in the upper steam chamber, when the pressure increases to a certain level, the gaseous working medium flows out along the outlet pipeline, the amount of working medium in the cold plate decreases, and the new liquid working medium is driving Re-flow under the action of force.

When the heating heat flow of the heat source is small, the Ω-shaped channel of the microchannel itself produces capillary force on the working fluid, and the capillary force provides the driving force for the circulation of the working medium. At this time, the cold plate can be used as the evaporator in the loop heat pipe driven by the capillary pump. When the heating heat flow of the heat source is large, it is necessary to increase the flow rate of the working medium to increase the cooling capacity of the cold plate. The system uses a mechanical pump to drive the flow of the working medium. At this time, the cold plate can be used as an evaporator in the fluid circuit of the mechanical pump.

The specific structure design is as follows:

A microchannel cold plate with a compound channel heat pipe structure for a pump fluid circuit includes a microchannel bottom plate 11, a structural support 12, a spoiler baffle 13, a steam chamber 14, a sealing gasket 15, a heat-resistant cover plate 16, and fastening bolts 17. Inlet pipeline 18 and outlet pipeline 19, wherein:

The microchannel bottom plate 11 of the microchannel cold plate, the structural support 12 and the heat-resistant cover plate 16 are connected together using fastening bolts 17, between the microchannel bottom plate 11 and the structural support 12 and the structural support 12 and the heat-resistant cover plate 16 A sealing gasket 15 is provided, and an inlet pipeline 18 and an outlet pipeline 19 are respectively installed at both ends of the structural support 12 .

There are a plurality of Ω-shaped grooves arranged along the direction of the vertical inlet pipeline on the described microchannel bottom plate 11, the groove spacing is 1.6mm, and the number of grooves is determined by the width of the cold plate; the section of the Ω-shaped grooves includes rectangle and circle The diameter of the circular part is D=0.8-1.2mm, the width of the rectangular part is L=0.2mm, and the height H=0.5-2mm. The total depth of the Ω-shaped channel is not less than the outer diameter of the inlet pipeline 18.

The structural support 12 has round holes of different sizes on the sides of the vertical Ω-shaped channel, that is, the short side end faces, wherein the small holes are connected to the inlet pipeline 18, and the large holes are connected to the outlet pipeline 19.

The spoiler baffle 13 is a semicircular tube with a circular opening, the opening is left-right symmetrical about the center line of the baffle, the diameter of the hole gradually expands from the inside to the outside about the axis of symmetry, and the hole spacing increases sequentially in an arithmetic sequence; The flow baffle 13 is welded and fixed on the structural support 12 near the small hole side, parallel to its short side.

The lower surface of the heat-resistant cover plate 16 is a U-shaped boss, and the short side of the boss is close to the side of the inlet pipeline 18 .

The utility model has the advantages of:

The cross-section of the microchannel in the microchannel cold plate is designed to be Ω-shaped with reference to the high-performance channel heat pipe, which can provide a certain capillary driving force while providing high heat exchange capacity. When the heating heat flow of the heat source is small, the capillary force drives the working medium to flow in the system, and the liquid working medium undergoes a phase change and overflows when heated, and flows back under the action of capillary force after condensation. When the heat flow of the heating heat source is large, the flow rate of the working medium is increased by the drive of the mechanical pump, and more liquid working medium per unit time undergoes a phase change in the cold plate, increasing the cooling capacity of the cold plate. The cold plate can be used simultaneously as an evaporator in a fluid circuit driven by capillary force and a mechanical pump to meet different heat exchange requirements.

Description of drawings

Fig. 1 The pump fluid circuit system diagram under two working conditions.

Figure 2 Appearance of the microchannel cold plate.

Fig. 3 Front sectional view of the microchannel cold plate.

Fig. 4 Side sectional view of the microchannel cold plate.

Figure 5. Channel inlet shunt structure of microchannel cold plate.

detailed description

The pump fluid circuit mainly includes two operating conditions, as shown in Figure 1. When the cooling heat load is small, the working condition one opens the valve 3 and short-circuits the mechanical pump 5 . When the heat load of the system is relatively large, the valve 3 is closed and the liquid reservoir 4 and the pump 5 are connected.

The cold plate mainly includes a microchannel bottom plate 11, a structural support 12, a spoiler baffle 13, a steam chamber 14, a sealing gasket 15, a heat-resistant cover plate 16, fastening bolts 17, an inlet pipeline 18, and an outlet pipeline 19. When designed as a detachable structure, use fastening bolts 17 to connect according to the connection sequence of the microchannel bottom plate 11, structural support 12, and heat-resistant cover plate 16 from bottom to top. A sealing gasket 15 is used to seal between the heat-resistant cover plates 16 respectively. The openings on both sides of the structural support 12 and the inlet pipeline 18 and outlet pipeline 19 are connected by socket welding. The micro-channel bottom plate 11 is made of metal materials with high thermal conductivity, such as copper and aluminum, and processed by slow wire cutting. The structural support 12, the inlet pipeline 18, and the outlet pipeline 19 are made of low thermal conductivity metal, such as stainless steel; the structural support 12 can be cast or turned, and the roughness of the sealing surface must be ensured. The heat-resistant cover plate 16 is made of heat-resistant tempered and quartz glass suitable for high temperature. Both ends of the spoiler baffle 13 are welded and fixed on the structural support 12 .

When working, the bottom mounting surface absorbs the heat from the heat source and transfers it evenly to the surface of the microchannel, and the liquid working fluid in the channel undergoes phase transformation into a gaseous working medium when heated. As the gaseous working medium continues to form and leave the channel to gather in the upper steam chamber, when the pressure increases to a certain level, the gaseous working medium flows out along the outlet pipeline, the amount of working medium in the cold plate decreases, and the new liquid working medium is driving Re-flow under the action of force.

The above structure ensures that after the fluid flows into the cold plate from the inlet pipeline, it first flows through the microchannel, is heated and vaporized, then enters the upper steam chamber, and finally flows out through the outlet pipeline. The volume of the steam chamber can be adjusted according to different working fluids. When there is no need to adopt a visual and detachable design, the cover plate 16 and the structural support 12 are integrated, and are connected with the microchannel bottom plate 11 by vacuum brazing. At the same time, the sealing gasket 15 and the fastening bolt 17 can be omitted, and the cooling effect can be reduced. board thickness.

Claims (5)

1. A microchannel cold plate with composite channel heat pipe structure for pump fluid circuit, comprising microchannel bottom plate (11), structural support (12), spoiler baffle (13), steam chamber (14), sealing gasket (15), heat-resistant cover plate (16), fastening bolt (17), inlet pipeline (18), outlet pipeline (19), it is characterized in that: The microchannel bottom plate (11), structural support (12) and heat-resistant cover plate (16) of described microchannel cold plate use fastening bolt (17) to link together, and microchannel bottom plate (11) and structural support (12 ) and the structural support (12) and the heat-resistant cover plate (16) have a sealing gasket (15), and the inlet pipeline (18) and the outlet pipeline (19) are respectively installed at the two ends of the structural support (12). 2. the microchannel cold plate of a kind of pump fluid circuit according to claim 1 composite channel heat pipe structure, it is characterized in that: on the described microchannel bottom plate (11) there are a plurality of along vertical inlet pipeline direction arranged The Ω-shaped channel, the groove spacing is 1.6mm, and the number of channels is determined by the width of the cold plate; the section of the Ω-shaped channel includes two parts: rectangular and circular, wherein the diameter of the circular part is D=0.8-1.2mm, and the rectangular The partial width L=0.2mm, the height H=0.5-2mm, and the total depth of the Ω-shaped groove is not less than the outer diameter of the inlet pipeline (18). 3. the microchannel cold plate of a kind of pump fluid circuit according to claim 1 composite channel heat pipe structure, it is characterized in that: described structural support (12) is on the side of vertical Ω-shaped channel, i.e. the short side end face Open a circular hole of different sizes on each, wherein the small hole links to each other with the inlet pipeline (18), and the large hole links to each other with the outlet pipeline (19). 4. the microchannel cold plate of a kind of pump fluid circuit according to claim 1 composite channel heat pipe structure, it is characterized in that: described spoiler baffle (13) is the semicircular pipe with circular opening, The opening is left-right symmetrical about the center line of the baffle, and the diameter of the hole gradually expands about the axis of symmetry from the inside to the outside, and the hole spacing increases sequentially in an arithmetic sequence; the spoiler baffle (13) is fixed on the structural support (12) on the side close to the small hole ) parallel to its short side. 5. A kind of microchannel cold plate with compound channel heat pipe structure for pump fluid circuit according to claim 1, characterized in that: the lower surface of the heat-resistant cover plate (16) is a U-shaped boss, the convex The short side of the platform is close to the inlet pipeline (18) side.