CN210862316U

CN210862316U - Heat transfer system

Info

Publication number: CN210862316U
Application number: CN201921580527.0U
Authority: CN
Inventors: 谢龙; 谢大为
Original assignee: Shandong Zhaowa Thermal Energy Technology Co ltd
Current assignee: Shandong Zhaowa Thermal Energy Technology Co ltd
Priority date: 2019-09-20
Filing date: 2019-09-20
Publication date: 2020-06-26
Anticipated expiration: 2029-09-20

Abstract

The application provides a heat transfer system, including evaporimeter, vapour pipeline, condenser, liquid pipeline and reservoir. The evaporator, the steam pipeline, the condenser and the liquid pipeline are communicated in sequence to form a closed heat transfer loop. The heat transfer loop is internally provided with a heat transfer working medium. The heat transfer working medium is vaporized in the evaporator to form steam. The steam reaches the condenser through the steam pipeline, and forms liquid after condensation liquefaction. The liquid reaches the liquid storage device through the liquid pipeline and then flows back to the evaporator through the liquid storage device. A capillary structure is arranged in the evaporator. The radius of the meniscus of the capillary structure is not less than the capillary equivalent aperture of the capillary structure. The heat transfer system that this application provided can utilize the difference in temperature between evaporimeter and the condenser to realize the self-loopa flow of heat transfer working medium, and capillary structure in the evaporimeter helps strengthening heat transfer system's phase transition heat transfer rate, and the setting of the radius of capillary structure meniscus can further promote heat transfer system's heat transfer ability.

Description

Heat transfer system

Technical Field

The present application relates to the field of heat transfer, and more particularly, to a heat transfer system.

Background

Currently, high efficiency passive heat transfer technology is widely used in various heat utilization or control scenarios because it has high heat transfer capability and does not require external power. The heat pipe is used as the most common efficient passive heat transfer device, can transfer more heat under smaller temperature difference, and has heat transfer capability obviously superior to that of the traditional metal. However, the conventional heat pipe does not have the heat transfer capability of large heat quantity and high heat flow density, and has the disadvantages of low heat transfer speed, limited heat transfer distance, poor antigravity capability and the like, so that the heat transfer capability of the conventional heat pipe is limited, and the heat pipe cannot meet the heat transfer capability requirements in various heat utilization and heat control application scenes.

SUMMERY OF THE UTILITY MODEL

It is an object of embodiments of the present application to provide a heat transfer system that effectively increases heat transfer capacity.

A heat transfer system comprises an evaporator, a steam pipeline, a condenser, a liquid pipeline and a liquid storage device, wherein the evaporator, the steam pipeline, the condenser, the liquid pipeline and the liquid storage device are sequentially communicated to form a closed heat transfer loop, a heat transfer working medium is arranged in the heat transfer loop, the heat transfer working medium is vaporized in the evaporator to form steam, the steam reaches the condenser through the steam pipeline to be condensed and liquefied to form liquid, the liquid reaches the liquid storage device through the liquid pipeline and then flows back to the evaporator through the liquid storage device, a capillary structure is arranged in the evaporator, and the radius of a meniscus of the capillary structure is larger than or equal to the capillary equivalent aperture of the capillary structure.

The heat transfer system provided by the application is provided with a closed heat transfer loop (circulation loop), a liquid heat transfer working medium and a vapor heat transfer working medium exist in the whole circulation loop, the self-circulation of the heat transfer working medium in the circulation loop is realized through the temperature difference between an evaporator and a condenser, and external power is not needed. The capillary structure is arranged in the evaporator, so that the backflow of a vaporous working medium in the evaporator to a liquid pipeline can be prevented, the vapor-liquid separation in the evaporator can be realized, the boiling interface pressure in the evaporator is effectively reduced, an overheat boiling state is further established, the heat exchange strength of the vaporous heat transfer working medium and the liquid heat transfer working medium is increased in the phase-change full-period bubble growth and bubble polymerization rising process of the heat transfer working medium, and the phase-change heat exchange rate of a heat transfer system is further enhanced. And the radius of the meniscus of the capillary structure is set to be not less than the capillary equivalent pore size of the capillary structure, so that the heat exchange capacity of the heat transfer system can be further improved.

Optionally, the heat transfer working medium is a modified heat transfer working medium.

In this application, modified heat transfer working medium has less critical activation nucleation point radius, and less bubble breaks away from the diameter, higher bubble break away from the frequency for heat transfer working medium has higher phase change rate at the bubble nucleation of phase transition full cycle and bubble break away from the in-process, and then strengthens heat transfer system's phase transition heat transfer rate.

Optionally, the capillary structure is in the shape of a column or a sheet.

Optionally, the material of the capillary structure is a metal material.

Optionally, the liquid line includes a liquid sump structure disposed proximate to the evaporator.

In this application, set up the liquid pool structure through terminal (i.e. the position that the liquid pipeline is close to the evaporimeter) at the liquid pipeline and can prevent the palirrhea to the liquid pipeline of vapour state working medium in the evaporimeter, in order to realize the vapour-liquid separation, thereby help reducing the heat transfer working medium phase transition interfacial pressure in the evaporimeter, and then help making the heat transfer working medium in the evaporimeter reach the overheated state, make the growth of the bubble of phase transition full cycle and bubble polymerization in-process vapour state heat transfer working medium and liquid heat transfer working medium heat transfer intensity increase, and then strengthen heat transfer system's phase transition heat transfer rate.

Optionally, the liquid pool structure is a U-shaped structure bent towards the gravity direction.

Optionally, the height of the interface where the evaporator is connected to the steam pipeline is higher than the height of the interface where the evaporator is connected to the liquefaction pipe.

In this application, the interface place height through making evaporimeter and steam pipe connection is higher than the interface place height that evaporimeter and liquid pipe connection can prevent the palirrhea to the liquid pipe way of vapour state working medium in the evaporimeter, in order to realize vapour-liquid separation, thereby help reducing the heat transfer working medium phase transition interfacial pressure in the evaporimeter, and then help making the heat transfer working medium in the evaporimeter reach overheated state, make the growth of the bubble of phase transition full cycle and gaseous heat transfer working medium and the liquid heat transfer working medium heat transfer intensity of bubble polymerization in-process vapour state strengthen, and then strengthen heat transfer system's phase transition heat transfer rate.

Optionally, the heat transfer system is a cold guide assembly, and the evaporator includes an evaporating pipe bent back and forth and a first fin connected to the evaporating pipe.

Optionally, the heat transfer system is a heat transfer assembly, and the condenser includes a condensation duct and a second fin connected to and disposed around the condensation duct.

Optionally, the heat transfer system is a heat dissipation assembly, and the evaporator includes a body and a heat dissipation fin protruding from the body.

The details of one or more embodiments of the application are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the application will be apparent from the description and drawings, and from the claims.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments of the present application will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that those skilled in the art can also obtain other related drawings based on the drawings without inventive efforts.

Fig. 1 is a schematic structural diagram of a heat transfer system according to an embodiment of the present application.

Fig. 2 is a schematic diagram of an evaporator provided by a pressure-temperature change diagram of a heat transfer medium circulating in a heat transfer loop when the circulating power provided by an embodiment of the present application is gravity.

Fig. 3 is a schematic cross-sectional view illustrating a height difference between an opening of an evaporator communicating with a liquid pipeline and an opening of an evaporator communicating with a vapor pipeline according to an embodiment of the present application.

Fig. 4 is a cross-sectional view of an evaporator with a capillary structure disposed therein, which is connected to a vapor pipe and a liquid pipe, respectively, according to an embodiment of the present disclosure.

Fig. 5 is a cross-sectional view of a connection between a liquid line including a liquid pool structure and an evaporator according to an embodiment of the present disclosure.

Fig. 6 is a schematic structural diagram of a heat transfer system according to an embodiment of the present application.

Fig. 7 is a schematic structural diagram of a heat transfer system according to an embodiment of the present application.

Fig. 8 is a schematic structural diagram of a heat transfer system according to an embodiment of the present application.

Fig. 9 is a schematic structural diagram of a heat transfer system according to an embodiment of the present application.

Fig. 10 is a schematic structural diagram of a heat transfer system according to an embodiment of the present application.

Icon: heat transfer systems, 100, 200, 300, 400, 500, 600; evaporators, 11, 21, 31, 41, 51, 61; steam lines, 12, 22, 32, 42, 52, 62; condenser, 13, 23, 33, 43, 53, 63; fluid lines, 14, 24, 34, 44, 54, 64; reservoir, 15, 25, 35, 45, 55, 65; a heat transfer circuit, 101; evaporation lines, 111, 211; a steam line, 121; condensation ducts, 131, 331, 533; a liquid conduit, 141; a liquid storage conduit 151; a capillary structure, 112; a liquid bath structure, 142; a first fin, 212; reflux end, 2111; an evaporator end, 2112; a steam line, 311; a return line, 312; a plate member, 313; a second fin, 332; a body, 411; a heat sink, 412; a contact surface 4111; a heat dissipating surface, 4112; steam collecting ducts, 431, 531; a liquid collecting line, 432, 532; and a third fin 611.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

The utility model discloses the people of this application discovers through research, and the heat pipe as the high-efficient passive heat transfer device commonly used among the prior art, though can transmit more heat and do not need external power under less difference in temperature, but traditional heat pipe does not possess big heat, high heat flux density heat transfer capacity, and has heat transfer rate not high, and the heat transfer distance is limited, and shortcoming such as antigravity ability is poor, can not satisfy the heat transfer capacity demand in a lot of thermal utilization and the thermal control application scene.

Based on this, the application provides a heat transfer system that can effectively improve heat transfer capacity.

Referring to fig. 1, a heat transfer system 100 according to an embodiment of the present application includes an evaporator 11, a vapor line 12, a condenser 13, and a liquid line 14. The evaporator 11, the steam pipeline 12, the condenser 13 and the liquid pipeline 14 are sequentially connected end to form a closed heat transfer loop 101.

In this embodiment, the heat transfer system 100 further includes a reservoir 15. The accumulator 15 is connected to the liquid line 14 and communicates with the heat transfer circuit 101. An accumulator 15 is provided adjacent to the condenser 13.

In this embodiment, the evaporator 11 is provided with an evaporation pipeline 111 therein, the steam pipeline 12 is provided with a steam pipeline 121 therein, the condenser 13 is provided with a condensation pipeline 131 therein, the liquid pipeline 14 is provided with a liquid pipeline 141 therein, the evaporation pipeline 111, the steam pipeline 121, the condensation pipeline 131 and the liquid pipeline 141 are sequentially communicated to form the closed heat transfer loop 101. A liquid storage pipe 151 is provided inside the liquid storage 15. The liquid storage line 151 communicates with the liquid line 141 and is connected to the heat transfer circuit 101.

The evaporator 11, the steam pipe 12, the condenser 13, the liquid pipe 14 and the liquid reservoir 15 may be made of a metal material having good thermal conductivity, such as aluminum, copper, stainless steel, or a non-metal material, such as glass. The evaporator 11, the steam line 12, the condenser 13, the liquid line 14, and the accumulator 15 may be separately manufactured and connected by a welding process, or may be integrally formed. The evaporator 11, the steam pipeline 12, the condenser 13, the liquid pipeline 14 and the liquid reservoir 15 can be respectively manufactured by processes of extrusion, cold forging, inflation, drawing expansion and the like, and then are connected by processes of brazing, resistance welding, argon arc welding, high-energy beam welding, riveting, bonding, screwing and the like to form the closed heat transfer loop 102.

It can be understood that, in the present application, no limitation is imposed on what kind of process is specifically adopted to realize the connection of the evaporator 11, the steam pipeline 12, the condenser 13 and the liquid pipeline 14, as long as the steam pipeline 12, the condenser 13 and the liquid pipeline 14 are sequentially communicated end to end and the liquid reservoir 15 is connected to the liquid pipeline 14 to form the closed heat transfer loop 102.

It can be understood that the sizes and volumes of the evaporator 11, the steam pipeline 12, the condenser 13, the liquid pipeline 14 and the liquid storage device 15 can be matched and designed based on the physical properties of the heat transfer medium in the working temperature region and the requirement of heat transfer capacity, and therefore, the size and volume are not limited in the application.

A heat transfer medium (not shown) is disposed within heat transfer circuit 101. The heat transfer medium is driven to circulate in the heat transfer circuit 101 by the temperature difference between the evaporator 11 and the condenser 13. The heat transfer working medium can be organic working medium such as HCFC (hydrochlorofluorocarbon), HFC (hydrofluorocarbon) and the like, inorganic working medium such as R717 (ammonia), R728 (nitrogen), R764 (sulfur dioxide) and the like, or metal working medium such as Na, Li, Pb-based alloy and the like. In this embodiment, the heat transfer medium is in a gas-liquid two-phase state in the heat transfer circuit 101. In the embodiment, the heat transfer working medium absorbs heat in the evaporator 11 and is vaporized at the liquid-gas phase change interface to form steam; the steam reaches the condenser 13 through the steam pipeline 12; the vapor thermally vaporizes in the condenser 13 to form a liquid; the liquid is returned to the evaporator 11 via a liquid line 14. The specific process of the vapor thermally discharging and liquefying in the condenser 13 to form liquid comprises the steps of cooling, condensing and supercooling and liquefying the vapor in the condenser 13 to form liquid.

In this embodiment, the circulating power of the heat transfer working medium circulating in the heat transfer loop 101 may be gravity or capillary force. When the circulating power is gravity, the condenser 13 is located at a height greater than that of the evaporator 11. When the circulating power is capillary force, the heights of the positions of the condenser 13 and the evaporator 11 are not limited.

In this embodiment, the phase change process of the heat transfer working medium in the evaporator 11, in which the heat absorption evaporation is changed from liquid to gas, includes four stages, namely bubble nucleation, bubble growth, bubble detachment and bubble polymerization.

In the bubble nucleation stage, the critical activation nucleus of the heat transfer working mediumRadius of change point r_mCritical core of vaporization R_min＝2γT_s/rρ_vΔ T, where γ is the surface tension coefficient of the heat transfer medium, T_sIs the saturation temperature at local pressure, r is the latent heat of vaporization at saturation temperature, ρ_vIs the saturated steam density, and delta t is the superheat degree of the liquid working medium at the heating wall surface. The phase-change heat exchange intensity (or phase-change rate) on the heating wall surface depends on the total number of the activated nucleation points on the heating wall surface, and the size distribution density of the pits on the heating wall surface is approximate to a normal distribution function N with the starting point as the origin_rThus, the total number of activated nucleation sites

I.e. the radius r of the heating wall surface is larger than the critical activation nucleation point_mThe pits of (a) are all activation nucleation sites. The conventional method, which is capable of multiplying the number of activated nucleation sites by increasing the expectation and standard deviation of the normal distribution function, is generally to provide a porous structure on the heating wall surface of the evaporator 11. The porous structure may be provided on the heated wall surface of the evaporator 11 by sintering, machining, spraying, electrochemical methods, or the like.

In this embodiment, the heat transfer working medium is a modified heat transfer working medium, that is, a heat transfer working medium subjected to modification treatment. The modification treatment mode comprises adding additives such as nano carbon powder and the like into the heat transfer working medium, or mixing various heat transfer working media and the like. As mentioned above, the phase-change heat exchange intensity (or phase-change rate) on the heating wall surface depends on the total number of the activation nucleation points on the heating wall surface, and the pit size distribution density on the heating wall surface is approximate to a normal distribution function N with the origin as the origin_rThus, the total number of activated nucleation sites

I.e. the radius r of the heating wall surface is larger than the critical activation nucleation point_mThe pits of (a) are all activation nucleation sites. The use of the modified heat transfer medium as the heat transfer medium of the heat transfer system 100 enables to achieve a saturation temperature T_sAnd the superheat degree delta t of the heating wall surface of the evaporator 11 is constant, the heat transfer working medium has a smaller critical activation nucleation pointThe radius can increase the number of the activation nucleation points by several orders of magnitude, so that the phase change rate of the heat transfer working medium from liquid state to gas state is increased, and the heat exchange capacity of the heat transfer system 100 is further improved. In this embodiment, the modified heat transfer working medium comprises ethylene and FNiTQ-101 grade nickel carbonyl powder. The mass ratio of ethylene in the modified heat transfer working medium is between 90 and 95 percent, the mass ratio of FNiTQ-101 carbonyl nickel powder in the modified heat transfer working medium is between 5 and 10 percent, the radius of a critical activation nucleation point is less than 0.1 micron, the bubble separation diameter is less than 0.5 micron, and the bubble separation frequency is more than 350 Hz. It is understood that the critical activation nucleation site radius, the bubble detachment diameter and the air-pie detachment frequency are only examples and are not limited thereto.

In the bubble growth stage, the initial stage is a dynamic control stage, the growth of the bubbles is mainly governed by the thermal inertia force in the heat transfer working medium and the external surface tension, and the growth rate of the bubbles is higher; the later stage is a thermodynamic control stage, the duration is long, the growth rate of the bubbles is mainly governed by the heat transfer capacity from the heat transfer working medium to the bubbles, when the heat transfer working medium is saturated liquid, the growth rate of the bubbles is slow, and when the heat transfer working medium is superheated liquid, the growth rate of the bubbles is fast. In this embodiment, the heat transfer medium in the evaporator 11 is in an overheated state to increase the phase change rate of the heat transfer medium from a liquid state to a gaseous state, thereby increasing the heat exchange capability of the heat transfer system 100.

The diameter D of the bubble detached from the heated wall surface of the evaporator 11 in the bubble detaching step_dThe smaller the detachment frequency f, the higher the phase transition rate. Disengagement diameter D_dThe influencing factors of (1) include pressure, gravitational acceleration, inertia force and the like; the bubble detachment frequency f has a relationship

For the kinetic control phase, the index n is 2, and for the thermodynamic control phase, the index n is 1/2. In this embodiment, the modified heat transfer working medium is used as the heat transfer working medium of the heat transfer system 100, so that the heat transfer working medium has a smaller bubble detachment diameter D_dCorrespondingly, increasing the bubble detachment frequency f, thereby intensifying the heat transfer mediumThe phase change rate from liquid to gas, thereby increasing the heat transfer capacity of the heat transfer system 100.

In the bubble polymerization stage, the heat exchange between the bubbles and the liquid heat transfer working medium in the rising process can reach higher strength, so that the critical heat flow density under the working condition of high heat flow density can be improved by effectively discharging the bubbles. The polymerization and rising movement of the bubbles is very complex and involves complex vapor-liquid two-phase turbulence. The reasonable bubble discharge structure can be designed to effectively discharge bubbles, so that the phase change rate is enhanced. In this embodiment, the heat transfer medium in the evaporator 11 is in an overheated state to increase the phase change rate of the heat transfer medium from a liquid state to a gaseous state, thereby increasing the heat exchange capability of the heat transfer system 100.

In the later thermodynamic control stage of the bubble growth stage, the bubble growth rate is mainly governed by the heat transfer capacity of the heat transfer working medium to the bubbles, the superheat degree of the liquid determines the growth rate of the bubbles, and in the bubble polymerization stage, the superheat degree of the liquid determines the heat exchange strength between the bubbles and the liquid in the rising process. The state that the main body temperature of the heat transfer working medium reaches the saturation temperature is a saturation state, and the bubbles slowly grow in the heat transfer working medium after being separated from the heating wall surface of the evaporator 11; the state that the main body temperature of the heat transfer working medium is lower than the saturation temperature is a supercooled state, and the bubbles can gradually disappear in the heat transfer working medium after being separated from the heating wall surface of the evaporator 11; the state that the main body temperature of the heat transfer working medium exceeds the saturation temperature is an overheat state, and the bubbles can grow rapidly in the heat transfer working medium after being separated from the wall surface, so that the bubbles can be discharged, and the phase change rate of the heat transfer working medium from a liquid state to a gas state is further improved. In this embodiment, the phase change rate of the heat transfer medium from a liquid state to a gas state can be increased by making the heat transfer medium in an overheated state in the evaporator 11, so as to improve the heat exchange capability of the heat transfer system 100.

For the heterogeneous boiling of the heat transfer working medium on the heating wall surface of the evaporator 11, the heat is mainly from the heating of the heating wall surface, and the heat transfer working medium body is difficult to obtain a larger superheat degree in a wall surface heating mode, so that the boiling point of the heat transfer working medium can be reduced in a mode of reducing the phase change interface pressure (namely the pressure of the interface of the heat transfer working medium converted from a liquid state to a gaseous state), and the heat transfer working medium is in an overheat state under the condition that the heat transfer working medium obtains the heat through the wall surface heating. Specifically, in this embodiment, the evaporator 11, the vapor pipe 12, the condenser 13, and the liquid pipe 14 are sequentially connected end to form a closed heat transfer loop 101, and the phase-change interface pressure in the evaporator 11 is reduced by vapor-liquid separation, so as to reduce the boiling point of the heat transfer working medium.

Referring to fig. 2, a pressure-temperature variation diagram of the heat transfer medium circulating in the heat transfer circuit 101 when the circulating power is gravity is shown. In the figure, point 1 is located at a position corresponding to the pressure and temperature of the evaporation interface in the evaporator 11; the line segment from point 1 to point 2 corresponds to the heat transfer working medium and forms steam through heat absorption and evaporation in the evaporator 11, the pressure and temperature change and the pressure difference between point 2 and point 1 can be delta P in the process that the steam is continuously heated in the evaporator 11 to form superheated steam_evaRepresents; the line segment from point 2 to point 3 corresponds to the change in pressure and temperature during the steam flow in the steam line 12, and the pressure difference between point 3 and point 2 can be represented by Δ P_vapRepresents; the line segment from point 3 to point 4 corresponds to the change of pressure and temperature in the process of cooling steam in the condenser 13, the line segment from point 4 to point 5 corresponds to the change of pressure and temperature in the process of condensing steam into liquid in the condenser 13, the line segment from point 5 to point 6 corresponds to the change of pressure and temperature in the process of supercooling liquid in the condenser 13, the total pressure difference of heat transfer working medium can be used as delta P_conRepresents; the line segment from point 6 to point 8 corresponds to the change in temperature and pressure of the liquid during its return flow in the liquid line 14 to the evaporator 11, wherein point 7 corresponds to the pressure and temperature of the liquid in the reservoir 15 and the pressure difference between point 8 and point 6 can be represented by Δ P_ligAnd (4) showing. Gravity pressure difference delta P as circulating power_gTotal flow pressure loss Δ P_total＝ΔP_eva+ΔP_vap+ΔP_con+ΔP_lig。

When capillary force is used as circulation power and the evaporator 11 is under the gravity working condition (i.e. the height of the evaporator 11 is lower than that of the condenser 13), the pressure-temperature change diagram of the heat transfer working medium circulating in the heat transfer loop 101 and gravity are used as circulation powerThe pressure-temperature change diagram of the heat transfer working medium circulating in the heat transfer loop 101 is similar during force, and the difference is that when the capillary force is taken as the circulating power, the pressure difference of the heat transfer working medium circulating in the heat transfer loop 101 also comprises the flowing pressure difference delta P of the heat transfer working medium in the capillary structure_wic. Therefore, the capillary pressure difference Δ P as the circulation power_cTotal flow pressure loss Δ P_total＝ΔP_eva+ΔP_vap+ΔP_con+ΔP_liq+ΔP_wic. If the evaporator 11 is in the antigravity working condition, that is, the evaporator 11 is located at a position higher than the condenser 13, the capillary pressure difference Δ P as the circulating power_cNeed to provide a total flow resistance Δ P to overcome_totalAnd gravity head Δ P_gThe circulating power of (2). During the heat transfer system 100 reaching thermal equilibrium, the meniscus radius of the capillary structure within the evaporator 11 automatically adjusts to match the flow resistance of the heat transfer circuit 101. In this embodiment, the radius of the meniscus of the capillary structure in the evaporator 11 is greater than or equal to the capillary equivalent pore size, so as to improve the heat exchange capability of the heat transfer system 100.

As can be seen from fig. 2, the boiling interface temperature T of the heat transfer medium in the evaporator 11 is the boiling interface temperature T in the case of gravity as the circulation power or in the case of capillary force as the circulation power₁Pressure of P₈Temperature T at this time₁Reaches the saturation temperature, pressure P₈Below the saturation pressure, the heat transfer medium in the evaporator 11 is brought to a superheated state.

In this application, the accessible following mode realizes the vapour-liquid separation to phase change interface pressure in reducing evaporimeter 11, and then reduces the boiling point of heat transfer working medium, and then makes under the condition that heat was obtained in the heat transfer working medium through the heating of 11 walls of evaporimeter, appears overheated state.

Referring to fig. 3, in the embodiment, the height of the opening where the evaporator 11 is communicated with the steam pipeline 12 is greater than the height of the opening where the evaporator 11 is communicated with the liquefaction pipe 14, that is, a height difference structure is formed between the opening where the evaporator 11 is communicated with the steam pipeline 12 and the opening where the evaporator 11 is communicated with the liquefaction pipe 14, and the height difference structure can prevent the vapor working medium in the evaporator from flowing back to the liquid pipeline to realize vapor-liquid separation, so that the boiling interface pressure in the evaporator is effectively reduced, the heat transfer working medium is helped to reach an overheated state in the evaporator 11, the phase change rate of the heat transfer working medium from a liquid state to a gaseous state is increased, and the heat exchange capability of the heat transfer system 100 is increased.

Referring to fig. 4, in the present embodiment, a capillary structure 112 is disposed in the evaporator 11, the capillary structure 112 is disposed to prevent a vapor working medium in the evaporator from flowing back to the liquid pipeline, so as to achieve vapor-liquid separation, thereby effectively reducing a boiling interface pressure in the evaporator, and further facilitating the heat transfer working medium to reach an overheat state in the evaporator 11, thereby increasing a phase change rate of the heat transfer working medium from a liquid state to a gas state, and further increasing a heat exchange capability of the heat transfer system 100, the capillary structure 112 is disposed at an end of the evaporator 11 close to the liquid pipeline 14^-14m². It can be understood that the capillary structure with the above average equivalent pore size, open porosity and permeability can delay the liquid heat transfer working medium from flowing back to the evaporator 11, thereby facilitating the vapor-liquid separation, however, for the heat transfer system with different application conditions, the average equivalent pore size, open porosity and permeability of the capillary structure can be designed accordingly according to the requirement, and the application is not limited thereto.

Referring to fig. 5, in the present embodiment, the liquid pipeline 14 includes a liquid pool structure 142. The liquid pool structure 142 is close to the interface where the liquid pipeline 14 is connected with the evaporator 11, and the structure can prevent the vapor working medium in the evaporator from flowing back to the liquid pipeline to realize vapor-liquid separation, thereby effectively reducing the boiling interface pressure in the evaporator, further helping the heat transfer working medium to reach an overheat state in the evaporator 11, further improving the phase change rate of the heat transfer working medium from liquid state to gas state, and further improving the heat exchange capacity of the heat transfer system 100. In this embodiment, the liquid pool structure 142 is a U-shaped structure recessed toward the gravity direction.

It can be understood that, in the present application, the filling amount of the heat transfer medium in the heat transfer loop 101 may be designed according to the size and volume of the evaporator 11, the steam pipeline 12, the condenser 13, the liquid pipeline 14 and the liquid reservoir 15, the physical property of the heat transfer medium in the heat transfer loop 101, and the required heat transfer capacity, which is not limited in the present application, as long as the error between the actual filling amount and the design value of the filling amount is less than 1%. The heat transfer working medium needs to be filled with high-precision filling and sealing complete equipment, and the application does not limit the equipment.

It is understood that in other embodiments, the reservoir 15 is internalized to the end of the fluid line. The evaporator 11, the steam pipeline 12, the condenser 13 and the liquid pipeline 14 are connected end to end in sequence, and a closed heat transfer loop 101 is formed in the evaporator.

The structure of the heat transfer system provided by the present application in different application scenarios is described below. It is to be understood that, since specific matters regarding the structure of the heat transfer system have been described above, only the general structure of the heat transfer system in a specific application scenario will be described below, and the specific structure of the heat transfer system may be referred to together with the description of the heat transfer system 100 above.

Application scenario 1: referring to fig. 6, in an embodiment of the present application, the heat transfer system 200 is a cold conduction assembly for conducting cold for a semiconductor refrigerator or a stirling refrigerator.

The cold conducting assembly comprises an evaporator 21, a steam pipeline 22, a condenser 23, a liquid pipeline 24 and a liquid storage device 25. The evaporator 21, the steam pipeline 22, the condenser 23, the liquid storage 25 and the liquid pipeline 24 are communicated in sequence to form a closed heat transfer loop. In this embodiment, the evaporator 21, the steam pipe 22, the condenser 23, the liquid reservoir 25 and the liquid pipe 24 may be connected in sequence by a brazing process to form a closed heat transfer loop. A modified heat transfer working medium (not shown) is arranged in the heat transfer loop. In this embodiment, the modified heat transfer working medium comprises ethylene and FNiTQ-101 grade nickel carbonyl powder. The mass ratio of the ethylene in the modified heat transfer working medium ranges from 90% to 95%. The mass ratio of FNiTQ-101 grade carbonyl nickel powder in the modified heat transfer working medium is between 5 and 10 percent. When the cold guide component works, the heat transfer working medium in the evaporator 21 is in an overheat state.

The evaporator 21 includes an evaporation tube 211 bent back and forth and a first fin 212 connected to the evaporation tube 211. The evaporation tube 211 and the first fin 212 are made of a metal material (e.g., copper, aluminum, etc.) having a good thermal conductivity. In this embodiment, the evaporation pipe 211 is made of copper, and the first fin 212 is made of aluminum. The evaporation pipe 211 is connected to the first fin 212 by an expansion process. In this embodiment, the evaporation pipe 211 is bent back and forth in the same plane. Alternatively, the plurality of bending points located on the same side of the evaporation pipe 211 are located on the same straight line. The evaporation pipe 211 includes a return end 2111 and an evaporation end 2112. A fluid line 24 is connected between the return 2111 and the reservoir 25. A vapor line 22 is connected between the evaporation end 2112 and the condenser 23.

The condenser 23 is made of a metal material (e.g., copper, aluminum, etc.) having a good heat conductive property. In this embodiment, the condenser 23 is made of aluminum, which is a metal material, by an extrusion process.

In this embodiment, the circulating power of the heat transfer medium in the heat transfer loop is gravity. The evaporator 21 is located at a lower level than the condenser 23.

In the embodiment, the cold transfer capacity Q of the cold conduction assembly is more than or equal to 200W, and the thermal resistance R is less than or equal to 0.01 ℃/W.

Application scenario 2: referring to fig. 7, in an embodiment of the present application, a heat transfer system 300 is a heat transfer component for collecting heat of a solar water heater.

The heat transfer assembly includes an evaporator 31, a vapor line 32, a condenser 33, a liquid line 34, and a liquid reservoir 35. The evaporator 31, the steam line 32, the condenser 33, the reservoir 25 and the liquid line 24 are sequentially communicated to form a closed heat transfer circuit. In this embodiment, the evaporator 31, the steam pipe 32, the condenser 33, the liquid reservoir 25 and the liquid pipe 24 are connected by a brazing process to form a closed heat transfer circuit.

In the present embodiment, the evaporator 31 has a substantially flat plate shape, and includes a vapor pipe 311 connected to the vapor pipe 32, a return pipe 312 connected to the liquid pipe 34, and an evaporation pipe (not shown) connected between the vapor pipe 311 and the return pipe 312. In this embodiment, the steam pipe 311 is disposed in parallel with the return pipe 312. The steam pipe 311 is located at a height greater than that of the return pipe 312. The number of the evaporation pipes is plural, and plural evaporation pipes 313 are connected in parallel between the steam pipe 311 and the return pipe 312. In this embodiment, to increase the heat receiving area, the evaporator 31 includes a plurality of plate members 313 arranged at intervals. A plurality of plates 313 are connected between the steam pipe 311 and the return pipe 312. The evaporation pipe is opened on the plate 313, and both ends are respectively communicated with the steam pipe 311 and the return pipe 312. In this embodiment, each plate 313 has at least one evaporation tube. In this embodiment, the evaporator 31 is fabricated by a microchannel brazing process.

The condenser 33 is connected to a water tank of the solar water heater. The condenser 33 includes a condensing duct 331 and a second fin 332. The second fins 332 are connected to the condensing pipe 331 and arranged around the condensing pipe 331, so as to increase the heat dissipation area and improve the heat dissipation efficiency. The condensing duct 331 and the second fin 332 are made of a metal material (e.g., copper, aluminum, etc.) having a good thermal conductivity. In this embodiment, the condensing duct 331 and the second fin 332 are made of copper. The condensation duct 331 and the second fin 332 are connected by an expansion process.

The heat transfer loop is internally provided with a modified heat transfer working medium. In this embodiment, the modified heat transfer working medium includes isobutane, dimethyl ether, difluoroethane and copper nanoparticles. The mass ratio of the isobutane in the modified heat transfer working medium is 30-50%; the mass ratio of the dimethyl ether in the modified heat transfer working medium ranges from 20% to 30%; the mass ratio of the difluoroethane in the modified heat transfer working medium ranges from 10% to 20%; the mass ratio of the nano copper powder in the modified heat transfer working medium ranges from 2% to 5%. In operation, the heat transfer medium is superheated within evaporator 31. The circulating power of the heat transfer working medium in the heat transfer loop is gravity, and the height of the position of the condenser 33 is larger than that of the position of the evaporator 31.

In the embodiment, the heat transfer capacity Q of the heat transfer component is more than or equal to 5000W, and the energy efficiency coefficient CTP is more than or equal to 0.85, which is about 2 times of the national first-level energy efficiency coefficient standard.

Application scenario 3: referring to fig. 8, in an embodiment of the present application, a heat transfer system 400 is a heat dissipation assembly for dissipating heat of chips such as an Insulated Gate Bipolar Transistor (IGBT) and a thermoelectric generation chip.

The heat sink assembly includes an evaporator 41, a vapor line 42, a condenser 43, a liquid line 44, and a liquid reservoir 45. The evaporator 41, the steam line 42, the condenser 43, the liquid line 44 and the liquid reservoir 45 are sequentially communicated to form a closed heat transfer loop. The evaporator 41, the steam pipeline 42, the condenser 43, the liquid pipeline 44 and the liquid storage device 45 are communicated in sequence by adopting a brazing process to form a closed heat transfer loop.

The evaporator 41 includes a body 411, an evaporation duct (not shown) disposed in the body 411, and a heat sink 412 protruding from the body 411. In this embodiment, the body 411 includes a contact surface 4111 contacting the heat dissipation member and a heat dissipation surface 4112 opposite to the contact surface 4111. The heat sink 412 protrudes from the heat dissipating surface 4112. The heat dissipation performance of the heat dissipation assembly is improved by the heat dissipation plate 412. The evaporator 41 may be made of aluminum by an extrusion process.

The condenser 43 has a substantially flat plate shape, and includes a steam collecting duct 431 connected to the steam pipe 42, a liquid collecting duct 432 connected to the liquid pipe 44, and a condensing duct 433 connected between the steam collecting duct 431 and the liquid collecting duct 432. The condenser 43 is made of aluminum alloy by a blown-up process.

The modified heat transfer working medium is arranged in the heat transfer loop. In this example, the modified heat transfer working medium includes trans-1-chloro-2-phenylthio cyclohexane, n-propane, and FNiTQ-101 grade nickel carbonyl powder. The mass ratio of the trans-1-chloro-2-thiophenyl cyclohexane in the modified heat transfer working medium ranges from 60% to 80%; the mass ratio of the n-propane in the modified heat transfer working medium ranges from 20% to 30%; the mass ratio of FNiTQ-101 grade carbonyl nickel powder in the modified heat transfer working medium is between 2 and 5 percent. In this embodiment, the circulating power of the heat transfer medium in the heat transfer loop is gravity. The condenser 43 is located at a height greater than that of the evaporator 41. During operation, the heat transfer medium is superheated within the evaporator 41.

In the embodiment, the heat transfer capacity Q of the heat dissipation assembly is more than or equal to 300W, and the thermal resistance R is less than or equal to 0.05 ℃/W.

Application scenario 4: referring to fig. 9, in an embodiment of the present application, a heat transfer system 500 is a heat dissipation assembly for dissipating heat under microgravity conditions.

The heat dissipation assembly includes an evaporator 51, a steam line 52, a condenser 53, a liquid line 54, and a liquid reservoir 55. The evaporator 51, the steam line 52, the condenser 53, the liquid line 54 and the liquid reservoir 55 are sequentially communicated to form a closed heat transfer circuit. In this embodiment, the evaporator 51, the steam line 52, the condenser 53, the liquid line 54, and the liquid reservoir 55 are sequentially connected to form a closed heat transfer circuit by a brazing process.

The evaporator 51 may be made of aluminum by an extrusion process.

The condenser 53 has a substantially flat plate shape, and includes a steam collecting duct 531 communicating with the steam pipe 52, a liquid collecting duct 532 communicating with the liquid pipe 54, and a condensing duct 533 connected between the steam collecting duct 531 and the liquid collecting duct 532. In this embodiment, the steam collecting duct 531 and the liquid collecting duct 532 are both honeycomb-shaped. The condensation duct 533 is linear. The condenser 53 may be made of aluminum alloy by a blown process.

The modified heat transfer working medium is arranged in the heat transfer loop. In this embodiment, the modified heat transfer working medium includes R717 refrigerant, n-propane, and FNiTQ-101 grade nickel carbonyl powder. The mass ratio range of the R717 refrigerant in the modified heat transfer working medium is between 50% and 60%, the mass ratio range of the n-propane in the modified heat transfer working medium is between 20% and 30%, and the mass ratio range of the FNiTQ-101 grade carbonyl nickel powder in the modified heat transfer working medium is between 10% and 20%. In this embodiment, the circulating power of the heat transfer medium in the heat transfer loop is capillary force. A capillary structure (not shown) is provided in the evaporator 51. During operation, the heat transfer medium is superheated within the evaporator 41.

The heat transfer capacity Q of the heat dissipation assembly is more than or equal to 500W, and the thermal resistance R is less than or equal to 0.02 ℃/W.

Application scenario 5: referring to fig. 10, in an embodiment of the present application, a heat exchange system 600 is a heat exchange assembly for exchanging heat for a closed space such as a base station, a data center, and the like.

The heat exchange assembly includes an evaporator 61, a steam line 62, a condenser 63, a liquid line 64 and a liquid reservoir 65. The evaporator 61, the steam line 62, the condenser 63, the liquid line 64 and the liquid reservoir 65 are sequentially communicated to form a closed heat transfer loop. In this embodiment, the evaporator 61, the steam line 62, the condenser 63, the liquid line 64, and the liquid reservoir 65 are sequentially connected to form a closed heat transfer circuit by a brazing process.

The evaporator 61 includes an evaporation tube (not shown) and a third fin (not shown) connected to the evaporation tube. The evaporation pipe can be manufactured by adopting a micro-channel brazing process. The connection of the evaporation pipe and the third fin can be realized through an expansion joint process. In this embodiment, the evaporation tube may be made of copper, and the third fin may be made of aluminum.

The condenser 63 includes a condensing pipe (not shown) and a fourth fin (not shown) connected to the condensing pipe. The condensing pipe can be manufactured by adopting a micro-channel brazing process. The connection of the condensing pipe and the fourth fin can be realized through an expansion joint process. In this embodiment, the condensing pipe may be made of copper, and the fourth fin may be made of aluminum.

The modified heat transfer working medium (not shown) is arranged in the heat transfer loop. In this embodiment, the modified heat transfer working medium includes propyne, dimethyl ether (DME), methyl chloride, and nano titanium powder. The mass ratio range of the propine in the modified heat transfer working medium is 40-60%, the mass ratio range of the dimethyl ether in the modified heat transfer working medium is 20-30%, the mass ratio range of the methyl chloride in the modified heat transfer working medium is 10-15%, and the mass ratio range of the nano titanium powder in the modified heat transfer working medium is 5-10%. In this embodiment, the circulating power of the heat transfer medium in the heat transfer loop is gravity. The evaporator 61 is at a lower level than the condenser 63. During operation, the heat transfer medium is superheated in the evaporator 61.

In the embodiment, the heat transfer capacity Q of the heat exchange component is more than or equal to 5000W, and the energy efficiency ratio COP is more than or equal to 15.

The above description is only an example of the present application and is not intended to limit the scope of the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A heat transfer system comprises an evaporator, a steam pipeline, a condenser, a liquid pipeline and a liquid storage device, wherein the evaporator, the steam pipeline, the condenser, the liquid pipeline and the liquid storage device are sequentially communicated to form a closed heat transfer loop, a heat transfer working medium is arranged in the heat transfer loop, the heat transfer working medium is vaporized in the evaporator to form steam, the steam reaches the condenser through the steam pipeline to be condensed and liquefied to form liquid, the liquid reaches the liquid storage device through the liquid pipeline and then flows back to the evaporator through the liquid storage device, a capillary structure is arranged in the evaporator, and the radius of a meniscus of the capillary structure is larger than or equal to the capillary equivalent aperture of the capillary structure.

2. The heat transfer system of claim 1, wherein the heat transfer fluid is a modified heat transfer fluid.

3. The heat transfer system of claim 1, wherein the capillary structure is in the form of a column or sheet.

4. The heat transfer system of claim 1, wherein the material of the wick structure is a metallic material.

5. The heat transfer system of claim 1, wherein the liquid conduit comprises a liquid pool structure disposed proximate the evaporator.

6. The heat transfer system of claim 5, wherein the liquid pool structure is a U-shaped structure that bends toward the direction of gravity.

7. The heat transfer system of claim 1, wherein the interface at which the evaporator is connected to the vapor line is at a higher elevation than the interface at which the evaporator is connected to the liquefaction tube.

8. The heat transfer system of claim 1, wherein the heat transfer system is a cold conduction assembly, and the evaporator comprises an evaporating pipe bent back and forth and a first fin connected with the evaporating pipe.

9. The heat transfer system of claim 1, wherein the heat transfer system is a heat transfer assembly, and the condenser comprises a condensing conduit and a second fin connected to and disposed around the condensing conduit.

10. The heat transfer system of claim 1, wherein the heat transfer system is a heat sink assembly and the evaporator comprises a body and fins projecting from the body.