Diamond micro-channel radiator

Abstract

According to the diamond micro-channel radiator, a micro-channel radiating structure is designed in a diamond, a plurality of fluid inlets are formed in the upper surface of the diamond, each fluid inlet corresponds to a fluid channel, the bottom of the diamond is closed, and the lower portions of the fluid channels are communicated. The fluid channels are evenly distributed on the diamond in the transverse direction and the longitudinal direction, the lower portions of the fluid channels are transversely arranged and communicated, and a plurality of mixing channels are formed in the lower portion of the interior of the diamond. According to the diamond micro-channel radiator, the micro-channel technology and the jet flow impact technology are combined, the problems of uneven heat dissipation in the flowing direction, large channel pressure drop, unstable two-phase flowing and the like can be solved, the jet flow technology is introduced into the diamond micro-channel radiator, the void fraction in the micro-channel can be reduced, the axial temperature gradient can be reduced, and the heat dissipation efficiency is improved. And the wall surface temperature distribution is more uniform, so that the critical heat flux density is improved.

Description

Technical Field

[0001] The invention relates to the field of micro heat exchangers, and in particular to a diamond microchannel radiator. Background Art

[0002] With the development of science and technology, electronic products are developing towards miniaturization, intelligence and high integration, resulting in a sharp increase in heat flux density. In order to ensure the constant surface temperature of microelectronic devices and remove excess heat in time, there is an urgent need for micro heat exchange devices with small size, light weight, compact structure and high heat transfer efficiency to effectively solve the heat dissipation problem. Microchannel radiators have been proven to be one of the most promising cooling methods. At present, the use of nanofluids, optimization of the interior of microchannels, secondary channels, or adding rough surfaces, increasing concentration or Reynolds number, reducing temperature, and enhancing temperature uniformity can significantly improve the heat dissipation performance of microchannels. However, with the further increase in heat dissipation, traditional microchannel materials gradually show their limitations.

[0003] Diamond has unique physical and chemical properties, especially its extremely high thermal conductivity (up to 2000W / (m·K)), which is 5 times that of copper at room temperature, and has excellent stability in harsh environments, making it an ideal material for various heat dissipation applications. At present, research on diamond heat dissipation mainly focuses on preparing diamond / metal (Cu, Al, etc.) composite materials by hot pressing diamond particles and metals, welding / depositing flaky diamond films on substrates with high thermal conductivity. However, due to the existence of thermal resistance, the high thermal conductivity of diamond cannot be fully utilized. Summary of the invention

[0004] The purpose of the present invention is to overcome the above technical deficiencies and provide a diamond microchannel heat sink, which combines the technology of microchannel and jet impact to solve the problems of uneven heat dissipation in the flow direction, large channel pressure drop and unstable two-phase flow in microchannel heat dissipation.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is a diamond microchannel heat sink, which has a microchannel heat dissipation structure designed inside the diamond, and a plurality of fluid inlets are provided on the upper surface of the diamond, each fluid inlet corresponds to a fluid channel, the bottom of the diamond is closed, and the plurality of fluid channels are interconnected at the bottom.

[0006] Preferably, the fluid inlet is a circular hole.

[0007] Preferably, the fluid channel is a tapered channel that is wider at the top and narrower at the bottom.

[0008] Furthermore, the fluid channels are evenly arranged in the horizontal and vertical directions on the diamond, and the fluid channels are arranged horizontally and penetrated at the bottom to form multiple mixing channels at the bottom of the diamond.

[0009] Furthermore, a plurality of transverse channels are formed between the fluid channels along the longitudinal direction, and the transverse channels are vertically distributed with the mixing channels below the diamond interior and are connected below the transverse channels.

[0010] Preferably, the fluid used for heat dissipation is one or more of nano-Al2O3, CuO, CNT, TiO2 fluid, liquid metal Ga, In or its alloy, water, ammonia, carbon dioxide, Freon, methane, ethane, propane, ethylene, propylene.

[0011] Preferably, the diamond size range for the heat sink is 5mm×5mm×1mm~25mm×25mm×5mm, the fluid inlet distribution is 5×5~20×20, and the hole spacing range is 50μm<diamond length / number of fluid inlets+1<1mm.

[0012] Preferably, the upper diameter of the fluid inlet is 0.25 mm to 1.25 mm, the lower diameter of the fluid channel is 0.1 mm to 0.5 mm, the height of the fluid channel is 1 mm to 5 mm, and the taper range is 0° to 20°.

[0013] Preferably, the length ratio of the fluid channel to the diamond is 1:50 to 2:5, the width ratio is 1:10 to 1:250, and the height is 1:10 to 1:2.

[0014] Preferably, the ratio of the fluid outflow transverse channel to the diamond length is 7:10-9:10, the width ratio is 1:50-2:5, the height ratio is 1:10-1:2, and the wall thickness is 0.1mm-1.0mm.

[0015] The beneficial effects of the present invention are:

[0016] (1) Diamond microchannel heat sink combines the technologies of microchannel and jet impact to solve problems such as uneven heat dissipation in the flow direction, large channel pressure drop, and unstable two-phase flow.

[0017] (2) The introduction of jet technology into the diamond microchannel heat sink can reduce the cavitation fraction in the microchannel, reduce the axial temperature gradient, make the wall temperature distribution more uniform, and thus increase the critical heat flux density.

[0018] (3) Diamond microchannel heat sink uses diamond as the device material. The high thermal conductivity of diamond can improve the heat dissipation performance of local hot spots in compact high-temperature electronic components.

[0019] (4) The diamond microchannel heat sink can select the appropriate compound cooling fluid and fluid inlet arrangement according to the heat dissipation requirements, and is highly practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the internal structure of the radiator of the present invention.

[0021] Figure 2 It is a cross-sectional view of the internal structure of the radiator of the present invention.

[0022] Figure 3 It is a simulated temperature distribution diagram of the radiator of the present invention.

[0023] Figure 4 It is a simulated pressure distribution diagram of the radiator of the present invention. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0025] like Figure 1 , Figure 2 As shown, a diamond microchannel heat sink is designed with a microchannel heat dissipation structure inside the diamond. A plurality of fluid inlets 1 are provided on the upper surface of the diamond, each fluid inlet 1 corresponds to a fluid channel 2, the bottom of the diamond is closed, and a plurality of fluid channels 2 are interconnected at the bottom. The fluid inlet 1 is a circular hole. The fluid channel 2 is a conical channel that is wide at the top and narrow at the bottom. The fluid channels 2 are evenly arranged in the horizontal and vertical directions on the diamond, and the fluid channels 2 are arranged and connected in the horizontal direction at the bottom, forming a plurality of mixing channels 3 at the bottom of the diamond. A plurality of transverse channels 4 are formed between the fluid channels 2 in the longitudinal direction, and the transverse channels 4 are vertically distributed with the mixing channels 3 at the bottom of the diamond, and are connected at the bottom of the transverse channels 4. The fluid outflow transverse channel 4 is located above the mixing channel 3, and the fluids flowing out of each mixing channel 3 converge in the fluid outflow transverse channel 4, and after convergence, flow out of the diamond microchannel heat sink for cooling and circulation.

[0026] like Figure 3 , Figure 4 The figure shows the temperature and pressure simulation diagram after the radiator is working. It can be seen that the thermal conductivity of the modified radiator is better than that of the existing radiator.

[0027] Example 1

[0028] Taking fluid water as an example, Comsol software is used to simulate the fluid in a tiny unit of the diamond microchannel heat sink. The size of the tiny unit is 10mm×0.8mm×2mm, the inlet aperture is 0.25mm, the inlet hole distance is 2mm, the number of inlet holes is 14, the length of the fluid outflow transverse channel is 9.6mm, the height is 1.5, the width is 0.45mm, and the length of the bottom U-shaped fluid channel is 0.8mm, the width is 0.3mm, and the height is 1.5mm. The fluid inlet pressure is 5kPa, the fluid inlet velocity is 0.5m / s, and the simulated chip heat flux at the bottom is 2500W / cm2 The simulated chip was cooled using a tiny unit. After 90 minutes of simulation, the chip temperature dropped to 493.35K and the pressure drop was 7.75KPa.

[0029] Example 2

[0030] Taking fluid water as an example, Comsol software is used to simulate the fluid in a tiny unit of the diamond microchannel heat sink. The size of the tiny unit is 10mm×0.8mm×2mm, the inlet aperture is 0.25mm, the inlet hole distance is 2mm, the number of inlet holes is 14, the length of the fluid outflow transverse channel is 9.5mm, the height is 1.67, the width is 0.45mm, and the length of the bottom U-shaped fluid channel is 0.8mm, the width is 0.3mm, and the height is 1.5mm. The fluid inlet pressure is 5kPa, the fluid inlet velocity is 2.5m / s, and the simulated chip heat flux at the bottom is 2500W / cm 2 The simulated chip was cooled using a tiny unit. After 90 minutes of simulation, the chip temperature dropped to 382.49K and the voltage drop was 2.37×10 2 KPa.

Claims

1. A diamond microchannel heat sink, characterized in that: It designs a microchannel heat dissipation structure inside the diamond, and provides multiple fluid inlets on the upper surface of the diamond. Each fluid inlet corresponds to a fluid channel. The bottom of the diamond is closed, and multiple fluid channels are interconnected at the bottom.

2. The diamond microchannel heat sink according to claim 1, characterized in that: The fluid inlet is a circular hole.

3. The diamond microchannel heat sink according to claim 1, characterized in that: The fluid channel is a tapered channel which is wide at the top and narrow at the bottom.

4. The diamond microchannel heat sink according to claim 1, characterized in that: The fluid channels are evenly arranged in the horizontal and vertical directions on the diamond, and the fluid channels are arranged horizontally and penetrated at the bottom to form a plurality of mixing channels at the bottom of the diamond.

5. The diamond microchannel heat sink according to claim 4, characterized in that: A plurality of transverse channels are formed between the fluid channels along the longitudinal direction. The transverse channels are vertically distributed with the mixing channels below the diamond interior and are connected below the transverse channels.

6. The diamond microchannel heat sink according to claim 1, characterized in that: The fluid used for heat dissipation is one or more of nano-Al2O3, CuO, CNT, TiO2 fluid, liquid metal Ga, In or its alloy, water, ammonia, carbon dioxide, Freon, methane, ethane, propane, ethylene, and propylene.

7. The diamond microchannel heat sink according to claim 1, characterized in that: The diamond size range of the radiator is 5mm×5mm×1mm~25mm×25mm×5mm, the fluid inlet distribution is 5×5~20×20, and the hole spacing range is 50μm<diamond length / fluid inlet number+1<1mm.

8. The diamond microchannel heat sink according to claim 1, characterized in that: The upper diameter of the fluid inlet is 0.25 mm to 1.25 mm, the lower diameter of the fluid channel is 0.1 mm to 0.5 mm, the height of the fluid channel is 1 mm to 5 mm, and the taper range is 0° to 20°.

9. The diamond microchannel heat sink according to claim 1, characterized in that: The length ratio of the fluid channel to the diamond is 1:50 to 2:5, the width ratio is 1:10 to 1:250, and the height ratio is 1:10 to 1:

2.

10. The diamond microchannel heat sink according to claim 1, characterized in that: The ratio of the fluid outflow transverse channel to the diamond length is 7:10-9:10, the width ratio is 1:50-2:5, the height ratio is 1:10-1:2, and the wall thickness is 0.1mm-1.0mm.

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