CN110470161B - Liquid metal high-temperature pulsating heat pipe and test method - Google Patents
Liquid metal high-temperature pulsating heat pipe and test method Download PDFInfo
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
- F28D15/02—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes
- F28D15/04—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes with tubes having a capillary structure
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Abstract
The invention provides a liquid metal high-temperature pulsating heat pipe and a test method thereof, wherein the liquid metal high-temperature pulsating heat pipe comprises a high-temperature pulsating heat pipe, a high-temperature heating furnace connected with the high-temperature pulsating heat pipe, a cooling liquid block, a high-pressure pump, a constant-temperature liquid tank, a flowmeter, a filter, a cooling liquid valve and a measurement and control system, wherein the measurement and control system is in signal connection with each device; the constant temperature liquid tank, the high pressure pump, the filter, the cooling liquid valve, the liquid inlet tee joint, the cooling liquid block, the liquid outlet tee joint and the flow meter are sequentially connected, the flow meter is connected with the constant temperature liquid tank, and all the devices form a circulating connection loop; the front side of the cooling liquid block is provided with a channel, the channel is connected with a condensation section of the high-temperature pulsating heat pipe, and an insulation section of the high-temperature pulsating heat pipe is connected with a high-temperature heating furnace. The invention can meet the test requirement of the high-temperature pulsating heat pipe in a high-temperature environment, and the designed high-temperature pulsating heat pipe can stably work for a long time in the high-temperature environment.
Description
Technical Field
The invention relates to the technical field of pulsating heat pipe research, in particular to a liquid metal high-temperature pulsating heat pipe and a test method.
Background
The pulsating heat pipe (OHP) is a novel and efficient heat transfer element which is provided by Akachi in the early 90 s of the 20 th century and can be used under the conditions of tiny space and high heat flow density. The pulsating heat pipe is composed of a bent capillary tube, and a proper amount of working fluid is filled into the tube after the tube is vacuumized. When the working device works, the working medium absorbs heat to expand and boost in the heating section and flows to the low-temperature condensing section, the gas column is cooled, shrunk and cracked, and due to the fact that pressure difference exists between the two ends and pressure imbalance exists between adjacent pipes, the working medium can make oscillating motion between the heating section and the condensing section, and therefore heat transfer is achieved.
Pulsating heat pipes with operating temperatures in excess of 500 ℃ are generally referred to as high temperature pulsating heat pipes. Most of pulsating heat pipes produced and researched at present have the working temperature not exceeding 200 ℃, which restricts the application of the pulsating heat pipes in the high-temperature heat transfer fields of aerospace and the like. Therefore, the pulsating heat pipe which can stably work at high temperature for a long time is of great significance.
In order to guide engineering application, master the law of heat transfer performance of the high-temperature pulsating heat pipe and design the high-temperature pulsating heat pipe suitable for different working conditions, the heat transfer performance of the high-temperature pulsating heat pipe needs to be researched, and in the research process, the accuracy and reliability of experimental data need to be ensured. The existing pulsating heat pipe testing method can only meet the testing requirement in a medium-low temperature environment and cannot meet the testing requirement in a high-temperature environment, so that the establishment of a novel high-temperature pulsating heat pipe testing system has important significance.
Disclosure of Invention
According to the technical problems that the pulsating heat pipe in the prior art is difficult to stably work at high temperature for a long time and the existing pulsating heat pipe testing method cannot meet the testing requirement in a high-temperature environment, the liquid metal high-temperature pulsating heat pipe and the testing method are provided. The invention mainly uses the test system to provide the test condition under the high-temperature environment for the high-temperature pulsating heat pipe, measures and calculates the heat quantity taken away by the high-temperature pulsating heat pipe through the cooling liquid, measures and calculates the heat leakage, and more accurately measures the heat quantity transferred by the high-temperature pulsating heat pipe, thereby more accurately evaluating the heat transfer performance of the high-temperature pulsating heat pipe.
The technical means adopted by the invention are as follows:
a high-temperature pulsating heat pipe of liquid metal comprises a three-way liquid filling port and a stainless steel pipe array which integrates a heating section, a heat insulation section and a condensing section together, wherein two horizontal through ports of the three-way liquid filling port are connected with two ports of the stainless steel pipe array, and working media in the stainless steel pipe array are liquid metal and have high latent heat of vaporization at high temperature; the liquid metal is one or a combination of more than one of sodium-potassium alloy, sodium metal, potassium metal, cesium metal or rubidium metal, wherein the mass fraction of potassium in the sodium-potassium alloy is 25% -75%, the liquid metal has the characteristic of being liquid at normal temperature, a melting process can be omitted in a heating process, the high-temperature pulsating heat pipe is started more simply, the starting performance of the high-temperature pulsating heat pipe is improved, and the liquid filling difficulty is reduced.
Further, the liquid filling rate of the high-temperature pulsating heat pipe is 10% -90%.
Furthermore, the pipe of the high-temperature pulsating heat pipe is one or more of stainless steel, nickel-based alloy or Inconel nickel-based alloy, and has the characteristics of high temperature resistance and corrosion resistance, the pipe and the working medium have better compatibility at high temperature, and meanwhile, the pipe has stable performance in the working temperature region of the high-temperature pulsating heat pipe, so that the high-temperature pulsating heat pipe can be ensured to stably run for a long time in a high-temperature environment; the wall thickness of the high-temperature pulsating heat pipe is 0.5-3 mm, and the inner diameter of the high-temperature pulsating heat pipe meets the following formula:
in the formula: deThe inner diameter (m) of the high-temperature pulsating heat pipe, D is the starting critical pipe diameter of the pulsating heat pipe, phi is the liquid filling rate (%),
is the percentage (%) of the total pipe volume occupied by the liquid after heat addition, rhoL,0For the density of the liquid at the operating temperature before the addition of heat (kg/m)3)，ρL,avIs the average density (kg/m) of the liquid working medium after heat addition3) U is the rising speed (m/s) of the vapor bubble relative to the liquid, hcIs the latent heat of vaporization (J/kg) of working medium at cold end temperature, q is input power (J/s), and pgIs latent heat ratio (%).
The invention also provides a liquid metal high-temperature pulsating heat pipe test method for measuring the heat transfer performance of the high-temperature pulsating heat pipe, which is measured by a test system, wherein the test system comprises a high-temperature heating furnace, a cooling liquid block, a high-pressure pump, a constant-temperature liquid tank, a flowmeter, a filter, a cooling liquid valve and a measurement and control system which are connected with the high-temperature pulsating heat pipe, and the measurement and control system is in signal connection with the devices;
the constant-temperature liquid tank is connected with one side of the high-pressure pump, the other side of the high-pressure pump is connected with one side of the filter, the other side of the filter is connected with one side of the cooling liquid valve, the other side of the cooling liquid valve is connected with one side of the cooling liquid block through a liquid inlet tee joint, the other side of the cooling liquid block is connected with one side of the flow meter through a liquid outlet tee joint, the other side of the flow meter is connected with the constant-temperature liquid tank, all the devices form a circulating connection loop, cooling liquid discharged from the constant-temperature liquid tank flows along the anticlockwise direction and finally flows back to the constant-temperature liquid tank, and the cooling liquid realizes circulating reciprocating flow through the high-pressure pump; the front side of the outside of the cooling liquid block is provided with a channel matched with the external diameter of the high-temperature pulsating heat pipe, the channel is connected with the condensation section of the high-temperature pulsating heat pipe, the heat insulation section of the high-temperature pulsating heat pipe is connected with the high-temperature heating furnace, and the heating section of the high-temperature pulsating heat pipe is placed in the high-temperature heating furnace; the cooling liquid block is internally provided with a plurality of layers of channels, and the flowing of the cooling liquid in the channels transfers the heat of the condensation section of the high-temperature pulsating heat pipe to the cooling liquid, so that the high-temperature pulsating heat pipe is cooled; the filter is used for filtering impurities in the cooling liquid to protect the flowmeter; the flow meter is used for measuring the flow of the cooling liquid; the cooling liquid valve is used for adjusting the flow of the cooling liquid; the constant-temperature liquid tank is used for maintaining the temperature of the discharged cooling liquid to be constant; the temperature and the flow of the cooling liquid can be controlled by setting the parameters of the constant-temperature liquid tank, the high-pressure pump and the cooling liquid valve;
the test method is as follows: starting a high-pressure pump to enable cooling liquid to start to circulate, adjusting the flow of the cooling liquid by adjusting the opening of a cooling liquid valve and reading data of a flow meter, and filtering the cooling liquid through a filter to remove impurities; starting the constant-temperature liquid tank, adjusting the temperature of the cooling liquid and providing a stable cooling environment for the high-temperature pulsating heat pipe; the high-temperature heating furnace is adjusted to a low-power heating state for warming up, and in the warming up process, the thermocouple, the RTD temperature sensor and the measurement and control system are adjusted to ensure the accuracy of data; the heating temperature, the heating speed, the heating power and the inclination angle of the high-temperature pulsating heat pipe are controlled and adjusted by adjusting the parameter setting of the high-temperature heating furnace, the parameters of a multi-section heating process are set by adjusting the heating program of the high-temperature heating furnace, the heating speed and the target furnace temperature are adjusted and heat preservation is carried out, the heating power is kept constant after the high-temperature pulsating heat pipe works stably, and experimental data are recorded; and (4) closing the high-temperature heating furnace, reducing the temperature of the constant-temperature liquid tank, entering a cooling process, and ending the experiment till the cooling process is ended.
Further, the temperature range of the cooling liquid discharged from the constant-temperature liquid tank is 5-300 ℃.
Furthermore, the peripheries of the high-temperature pulsating heat pipe and the cooling liquid block are integrally wrapped by the heat-insulating layer, so that the heat of the condensation section of the high-temperature pulsating heat pipe is transmitted to the cooling liquid, and the heat transmitted by the high-temperature pulsating heat pipe can be accurately measured; the heat insulation layer is made of high-temperature-resistant heat insulation materials, at least 4 thermocouples are arranged inside and outside the heat insulation layer, and the average temperature inside and outside the heat insulation layer is measured through readings of the thermocouples inside and outside the heat insulation layer to obtain heat leakage.
Further, the liquid inlet tee bend with the liquid outlet tee bend all has RTD temperature sensor through threaded connection, RTD temperature sensor stretches into the central point that the coolant liquid pipeline put.
Furthermore, the high-temperature heating furnace is used for heating the high-temperature pulsating heat pipe, is of a sealed box structure, and is provided with a hearth upper cover at the top, a stepped hole is formed in the hearth upper cover, the high-temperature pulsating heat pipe extends into the high-temperature heating furnace through a middle through hole of the stepped hole, a heat insulation section of the high-temperature pulsating heat pipe is wrapped by a high-temperature-resistant heat insulation material and is arranged in the middle through hole in a direction perpendicular to the hearth upper cover, the top of the high-temperature heating furnace is provided with the hearth upper cover, and heating rods can be arranged on the front, the rear, the left and the right surfaces of the high-temperature heating furnace, so; the stepped hole and the high-temperature pulsating heat pipe which is vertically installed form a side gap, high-temperature-resistant heat-insulating materials are used for filling and sealing in the side gap, the stepped hole is machined, and the high-temperature-resistant heat-insulating materials are filled in the stepped hole, so that the heat-insulating materials can be fixed more stably, and the phenomenon that the heat-insulating materials fall off due to the fact that the hole is straight up and down can be avoided; the central positions of two sides of a furnace body of the high-temperature heating furnace are welded with flange plates, and angle adjusting devices composed of gear transmission mechanisms are mounted on the flange plates and used for adjusting the integral inclination angle of the high-temperature heating furnace and further adjusting the inclination angle of the high-temperature pulsating heat pipe, wherein the inclination angle ranges from 0 degree to 180 degrees; the heating temperature, the heating speed, the heating power and the inclination angle of the high-temperature pulsating heat pipe can be controllably adjusted by adjusting the parameter setting of the high-temperature heating furnace, the parameters of a multi-section heating process can be set by adjusting the heating program of the high-temperature heating furnace, the heating speed and the target furnace temperature are adjusted to carry out heat preservation, and the heating power is kept constant after the high-temperature pulsating heat pipe stably works.
Furthermore, the heating section, the heat insulation section and the condensing section of the high-temperature pulsating heat pipe are respectively provided with at least one thermocouple, and the transverse pipe above the condensing section of the high-temperature pulsating heat pipe is provided with at least one thermocouple; the thermocouples arranged on the high-temperature pulsating heat pipe are used for detecting the temperature change conditions of the heating section, the heat insulation section and the condensation section of each pipe on the high-temperature pulsating heat pipe to obtain a temperature curve and obtain the thermal resistance of the high-temperature pulsating heat pipe, so that the heat transfer performance of the high-temperature pulsating heat pipe is researched, the temperatures of the heating section and the condensation section can be measured through reading numbers of the thermocouples of the heating section and the condensation section, and the average temperature of the heating section and the condensation section can be calculated through averaging the reading numbers of the thermocouples.
Further, the thermal resistance of the high-temperature pulsating heat pipe can be obtained by the following formula:
in the formula: r is the thermal resistance (K/W) of the high-temperature pulsating heat pipe,
the average temperature (K) of the heating section when the high-temperature pulsating heat pipe stably operates,
the average temperature (K) and Q of the condensation section when the high-temperature pulsating heat pipe stably operateseHeating power (W) of the high-temperature pulsating heat pipe;
the heating power of the high-temperature pulsating heat pipe can be obtained by the following formula:
Qe＝CpqmΔT+q；
ΔT＝T1-T2；
in the formula: qeHeating power (W) for the high-temperature pulsating heat pipe, q is heat leakage (W), and q ismThe mass flow (kg/s) of the cooling liquid measured by the flowmeter, T1Temperature (K) measured by RTD temperature sensor at tee joint of liquid outlet2The temperature (K) measured by RTD temperature sensors at the three-way position of the liquid inlet, the delta T is the temperature difference (K) at the inlet and the outlet of the cooling liquid, and CpThe specific heat capacity of water (J/(kg. K)) at the operating temperature, (T)1+T2) The operating temperature (K) is/2;
the heat leakage can be determined by the following formula:
in the formula: q is heat leakage (W), K is the thermal conductivity (W/(m.K)) of the material of the insulating layer, A is the area (m) of the insulating layer2)，ΔTlThe temperature difference (K) between the inside and the outside of the heat-insulating layer, and L is the thickness (m) of the heat-insulating layer;
the proportion of heat leakage to the heating power of the high-temperature pulsating heat pipe is less than 10 percent, and the following formula is satisfied:
if the result obtained by calculation
The flow rate of the cooling liquid needs to be increased or the thickness of the heat-insulating material needs to be increased, and the experiment is carried out again and the result is calculated, so that the proportion of heat leakage to the heating power of the high-temperature pulsating heat pipe is ensured to be less than 10%.
Compared with the prior art, the invention has the following advantages:
1. the liquid metal high-temperature pulsating heat pipe and the testing method provided by the invention can meet the testing requirement of the high-temperature pulsating heat pipe in a high-temperature environment, and the designed high-temperature pulsating heat pipe can stably work for a long time in the high-temperature environment of more than 500 ℃.
2. The invention provides a liquid metal high-temperature pulsating heat pipe and a testing method thereof.A cooling liquid pipeline of a testing system is provided with two RTD temperature sensors, a filter and a high-precision flowmeter, wherein the RTD temperature sensors can be inserted into upper ports of a liquid inlet tee and a liquid outlet tee to measure the temperature of a cooling liquid inlet and a cooling liquid outlet so as to obtain the temperature difference of the cooling liquid inlet and the cooling liquid outlet, the filter can filter impurities in the cooling liquid, the flowmeter is protected, the flow stability can be ensured, the flowmeter measures the flow, and the heat transferred by the high-temperature pulsating heat pipe can be calculated through.
3. According to the liquid metal high-temperature pulsating heat pipe and the testing method, the plurality of thermocouples are arranged inside and outside the heat insulation layer wrapped by the condensation section of the high-temperature pulsating heat pipe, the temperature of the inner wall and the outer wall of the heat insulation layer is measured, and heat leakage can be calculated.
4. According to the liquid metal high-temperature pulsating heat pipe and the testing method provided by the invention, the cooling liquid system is adopted to measure and calculate the heat quantity taken away by the high-temperature pulsating heat pipe through the cooling liquid, and meanwhile, the heat leakage is measured and calculated, so that the heat quantity transferred by the high-temperature pulsating heat pipe can be more accurately measured, and the heat transfer performance of the high-temperature pulsating heat pipe can be more accurately evaluated.
In conclusion, the technical scheme of the invention can solve the problems that the pulsating heat pipe in the prior art is difficult to stably work at high temperature for a long time and the existing pulsating heat pipe test method cannot meet the test requirement in a high-temperature environment.
Based on the reason, the invention can be widely popularized in the fields of aerospace and the like which use the pulsating heat pipe to conduct high-temperature heat transfer.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a schematic structural diagram of a high-temperature pulsating heat pipe according to the present invention.
FIG. 2 is a schematic structural diagram of a test system according to the present invention.
FIG. 3 is a schematic structural diagram of a high temperature pulsating heat pipe and coolant block assembly of the present invention.
FIG. 4 is a schematic structural view of a furnace upper cover of the high temperature heating furnace of the present invention.
FIG. 5 is a distribution diagram of the thermocouple installation positions on the high-temperature pulsating heat pipe in the present invention.
FIG. 6 is a temperature curve diagram of the high temperature pulsating heat pipe start-up and the high temperature heating furnace temperature of 850 deg.C in the present invention.
FIG. 7 is a temperature profile of the high temperature furnace of the present invention at stages of 900 deg.C, 950 deg.C and 1000 deg.C, respectively.
FIG. 8 is a temperature profile of the high temperature furnace of the present invention at stages of 1050 ℃ and 1100 ℃.
FIG. 9 is a temperature profile of the high temperature furnace of the present invention at stages of 1150 ℃ and 1200 ℃.
FIG. 10 is a graph showing the temperature difference between the cold end and the hot end of the high-temperature pulsating heat pipe varying with power according to the present invention.
FIG. 11 is a graph of the thermal resistance of the high temperature pulsating heat pipe of the present invention as a function of power.
In the figure: 1. a first thermocouple; 2. a second thermocouple; 3. a third thermocouple; 4. a fourth thermocouple; 5. a fifth thermocouple; 6. a number six thermocouple; 7. a No. seven thermocouple; 8. a No. eight thermocouple; 9. a No. nine thermocouple; 10. a No. ten thermocouple; 11. a No. eleven thermocouple; 12. a No. twelve thermocouple; 13. a thirteen-numbered thermocouple; 14. a fourteen-gauge thermocouple; 15. a No. fifteen thermocouple; 16. a sixteen-gauge thermocouple; 17. seventeen thermocouples; 18. eighteen thermocouple; 19. a nineteen-size thermocouple; 20. a high temperature heating furnace; 21. a high temperature pulsating heat pipe; 22. cooling liquid blocks; 23. a liquid inlet tee joint; 24. a liquid outlet tee; 25. a flow meter; 26. a constant temperature liquid tank; 27. a high pressure pump; 28. a filter; 29. a coolant valve; 30. a three-way liquid filling port; 31. a stainless steel tube array; 32. a condensing section; 33. a thermally insulating section; 34. a heating section; 35. a stepped bore.
Detailed Description
It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
As shown in fig. 1, the present invention provides a liquid metal high temperature pulsating heat pipe, wherein the high temperature pulsating heat pipe 21 comprises a three-way liquid filling port 30 and a stainless steel pipe array 31 integrating a heating section 34, a heat insulation section 33 and a condensing section 32 together, two horizontal through ports of the three-way liquid filling port 30 are welded to two ports of the stainless steel pipe array 31, and the stainless steel pipe array 31 is filled with liquid metal as a working medium, which has high latent heat of vaporization at high temperature; the liquid metal is sodium-potassium alloy, the mass fraction of potassium in the sodium-potassium alloy is 25% -75%, the sodium-potassium alloy has the characteristic of being liquid at normal temperature, a melting process can be omitted in a heating process, the high-temperature pulsating heat pipe 21 is enabled to be simpler to start, the starting performance of the high-temperature pulsating heat pipe 21 is improved, and the liquid filling difficulty is reduced;
in this embodiment, the liquid filling rate of the high-temperature pulsating heat pipe 21 is 10% to 90%.
In this embodiment, the pipe of the high-temperature pulsating heat pipe 21 is stainless steel 310s, which has the characteristics of high temperature resistance and corrosion resistance, and the pipe has good compatibility with the working medium at high temperature, and meanwhile, the stainless steel 310s has stable performance in the working temperature region of the high-temperature pulsating heat pipe 21, so that the high-temperature pulsating heat pipe 21 can be ensured to stably operate for a long time in a high-temperature environment. In this embodiment, the wall thickness of the high-temperature pulsating heat pipe 21 is 0.5-3 mm, and the inner diameter satisfies the following formula:
in the formula: deThe inner diameter (m) of the high-temperature pulsating heat pipe, D is the starting critical pipe diameter of the pulsating heat pipe, phi is the liquid filling rate (%),
is the percentage (%) of the total pipe volume occupied by the liquid after heat addition, rhoL,0For the density of the liquid at the operating temperature before the addition of heat (kg/m)3)，ρL,avIs the average density (kg/m) of the liquid working medium after heat addition3) U is the rising speed (m/s) of the vapor bubble relative to the liquid, hcIs the latent heat of vaporization (J/kg) of working medium at cold end temperature, q is input power (J/s), and pgIs latent heat ratio (%).
Example 2
On the basis of embodiment 1, as shown in fig. 2 to 4, the invention further provides a liquid metal high-temperature pulsating heat pipe testing method for measuring the heat transfer performance of the high-temperature pulsating heat pipe, the testing method is measured by a testing system, the testing system comprises a high-temperature heating furnace 20 connected with the high-temperature pulsating heat pipe 21, a cooling liquid block 22, a high-pressure pump 27, a constant-temperature liquid tank 26, a flow meter 25, a filter 28, a cooling liquid valve 29 and a measurement and control system, and the measurement and control system is in signal connection with the above devices through data lines;
the right side of the constant temperature liquid tank 26 is connected with the left side of the high pressure pump 27 through a pipeline, the liquid outlet of the high pressure pump 27 is connected with the left side of the filter 28 through a pipeline, the right side of the filter 28 is connected with the left side of the cooling liquid valve 29 through a pipeline, the right side of the cooling liquid valve 29 is connected with the left side of the cooling liquid block 22 through a pipeline and a liquid inlet tee 23, the right side of the cooling liquid block 22 is connected with the left side of the flowmeter 25 through a liquid outlet tee 24 and a pipeline, the right side of the flow meter 25 is connected with a constant temperature liquid tank 26 through a pipeline, all the above devices form a circulating connection loop, cooling liquid discharged from the constant temperature liquid tank 26 flows along the anticlockwise direction and finally flows back to the constant temperature liquid tank 26, and the cooling liquid realizes circulating reciprocating flow through the high-pressure pump 27; a channel matched with the external diameter of the high-temperature pulsating heat pipe 21 is arranged on the front side of the outside of the cooling liquid block 22, a condensation section 32 of the high-temperature pulsating heat pipe 21 is embedded into the channel, a heat insulation section 33 in the middle of the high-temperature pulsating heat pipe 21 is connected with the high-temperature heating furnace 20, and a heating section 34 of the high-temperature pulsating heat pipe 21 extends into the high-temperature heating furnace 20; the installation lengths of the heating section 34, the heat insulation section 33 and the condensation section 32 are adjusted by adjusting the height of the cooling liquid block 22 and the length of the high-temperature pulsating heat pipe 21 penetrating into the high-temperature heating furnace 20; a plurality of layers of channels are arranged inside the cooling liquid block 22, and the heat of the condensation section 32 of the high-temperature pulsating heat pipe 21 is transferred to the cooling liquid by the flowing of the cooling liquid in the channels, so that the high-temperature pulsating heat pipe 21 is cooled; the filter 28 is used for filtering impurities in the cooling liquid and protecting the flowmeter 25; the flow meter 25 is used for measuring the flow rate of the cooling liquid, the flow meter is a high-precision mass flow meter, and the cooling liquid valve 29 is used for adjusting the flow rate of the cooling liquid within the measuring range of the flow meter; the constant temperature liquid tank 26 is used for maintaining the temperature of the discharged cooling liquid to be constant; the temperature and flow rate of the cooling liquid can be controlled by setting the parameters of the constant temperature liquid tank 26, the high pressure pump 27 and the cooling liquid valve 29.
In this embodiment, the temperature of the cooling liquid discharged from the constant temperature liquid tank 26 is in the range of 5 ℃ to 300 ℃.
In this embodiment, the peripheries of the high-temperature pulsating heat pipe 21 and the coolant block 22 are wholly wrapped by the insulating layer, so that heat of the condensation section 32 of the high-temperature pulsating heat pipe 21 is transferred to the coolant, and the heat transferred by the high-temperature pulsating heat pipe 21 can be accurately measured; the heat insulation layer is made of high-temperature-resistant heat insulation materials, 4 thermocouples are arranged inside and outside the heat insulation layer, the thermocouples are high-temperature-resistant ceramic Nextel sheath K-type thermocouples, and the average temperature inside and outside the heat insulation layer is measured through reading of the thermocouples inside and outside the heat insulation layer so as to obtain heat leakage.
In this embodiment inlet tee bend 23 with liquid outlet tee bend 24 all has RTD temperature sensor through threaded connection, and RTD temperature sensor's model is PT100, RTD temperature sensor stretches into the central point on coolant liquid pipeline and puts.
In this embodiment, the high temperature heating furnace 20 is used for heating the high temperature pulsating heat pipe 21, and is of a sealed box structure, the top of the high temperature heating furnace is provided with a furnace chamber upper cover, the furnace chamber upper cover is provided with a stepped hole 35, the high temperature pulsating heat pipe 21 extends into the high temperature heating furnace 20 through a middle through hole of the stepped hole 35, a heat insulation section 33 of the high temperature pulsating heat pipe is wrapped by a high temperature resistant heat insulation material and is installed in the middle through hole in a direction perpendicular to the furnace chamber upper cover, the top of the high temperature heating furnace 20 is provided with the furnace chamber upper cover, and heating rods can be installed on the front, rear, left and right surfaces of the high temperature heating furnace; the stepped hole 35 and the vertically installed high-temperature pulsating heat pipe 21 form a side gap, high-temperature-resistant heat-insulating materials are used for filling and sealing in the side gap, the high-temperature-resistant heat-insulating materials are filled in the stepped hole 35, the stepped hole is more stable, and the phenomenon that the heat-insulating materials fall off due to the fact that the holes are vertically arranged can be avoided; the central positions of two sides of the furnace body of the high-temperature heating furnace 20 are welded with flange plates, and angle adjusting devices composed of gear transmission mechanisms are mounted on the flange plates to adjust the integral inclination angle of the high-temperature heating furnace 20 and further adjust the inclination angle of the high-temperature pulsating heat pipe 21, wherein the inclination angle is 0-180 degrees; the heating temperature, the heating speed, the heating power and the inclination angle of the high-temperature pulsating heat pipe 21 can be controllably adjusted by adjusting the parameter setting of the high-temperature heating furnace 20, the parameters of a multi-section heating process can be set by adjusting the heating program of the high-temperature heating furnace 20, the heating speed and the target furnace temperature are adjusted to carry out heat preservation, and the heating power is kept constant after the high-temperature pulsating heat pipe 21 stably works.
In this embodiment, the heating section 34, the heat insulating section 33 and the condensing section 32 of the high temperature pulsating heat pipe 21 are respectively provided with at least one thermocouple, and the transverse pipe above the condensing section 32 of the high temperature pulsating heat pipe 21 is provided with at least one thermocouple; the thermocouple that is equipped with on the high temperature pulsating heat pipe 21 is high temperature resistant pottery Nextel sheath K type thermocouple, the thermocouple that is equipped with on the high temperature pulsating heat pipe 21 is used for detecting the temperature variation condition of heating section 34 and condensation segment 32 on the high temperature pulsating heat pipe 21, obtains the temperature curve, obtains the thermal resistance of high temperature pulsating heat pipe 21, and then studies the heat transfer performance of high temperature pulsating heat pipe 21, can record heating section 34, condensation segment 32 temperature through heating section 34, condensation segment 32 thermocouple reading, can calculate heating section 34, condensation segment 32 average temperature through getting the average to many thermocouple readings.
Example 3
In the embodiment, the high-temperature pulsating heat pipe 21 with the pipe material of 6mm in inner diameter and 1mm in wall thickness as the stainless steel 310s is selected for an experiment, the volume liquid filling rate of the working medium in the high-temperature pulsating heat pipe 21 is 45%, the working medium is sodium-potassium alloy, and the mass fraction of potassium is 75%. In this embodiment, a distribution diagram of thermocouple installation positions on the high-temperature pulsating heat pipe 21 is shown in fig. 5, 19 thermocouples are arranged on the high-temperature pulsating heat pipe 21, and a nineteen thermocouple 19 is arranged on a transverse pipeline at a three-way liquid filling port 30 of the stainless steel pipe array 31; the heating section 34, the heat insulation section 33 and the condensation section 32 of two adjacent pipes of the first elbow on the left side are respectively provided with a first thermocouple 1, a second thermocouple 2, a seventh thermocouple 7, an eighth thermocouple 8, a thirteenth thermocouple 13 and a fourteenth thermocouple 14; the heating section 34, the heat insulation section 33 and the condensation section 32 of two adjacent pipes of the first elbow on the right side are respectively provided with a fifth thermocouple 5, a sixth thermocouple 6, an eleventh thermocouple 11, a twelfth thermocouple 12, a seventeen thermocouple 17 and an eighteen thermocouple 18; a thermocouple is arranged in each of two selected bend pipes of the middle bend, a heating section 34, a heat insulation section 33 and a condensation section 32 of the two selected bend pipes are respectively provided with a third thermocouple 3, a fourth thermocouple 4, a ninth thermocouple 9, a tenth thermocouple 10, a fifteenth thermocouple 15 and a sixteenth thermocouple 16, and the thermocouples are all high-temperature resistant ceramic Nextel sheath K-type thermocouples.
The working process is as follows:
(1) firstly, fixing the heat insulation section 33 of the high-temperature pulsating heat pipe 21 in a stepped hole 35 of a hearth upper cover of the high-temperature heating furnace 20, adjusting the length of the heating section 34 of the high-temperature pulsating heat pipe 21 in the high-temperature heating furnace 20, then filling and sealing a side gap formed by the stepped hole 35 and the installed high-temperature pulsating heat pipe 21 with a high-temperature-resistant heat insulation material, and adjusting the high-temperature heating furnace 20 to a certain inclination angle after the heat insulation section 33 of the high-temperature pulsating heat pipe 21 is fixed, wherein the inclination angle is 90 degrees in the embodiment; and then the high-temperature pulsating heat pipe 21 and the cooling liquid block 22 are integrally wrapped in multiple layers by using high-temperature-resistant heat-insulating materials and are communicated with all equipment in the test system.
(2) The high pressure pump 27 is activated to start the circulation of the coolant, and the coolant flow rate is adjusted by adjusting the opening of the coolant valve 29 and reading the data of the flow meter 25 to reach a predetermined value and stabilize for 10 minutes, wherein the coolant is filtered by the filter 28 to remove impurities.
(3) And starting the constant-temperature liquid tank 26, adjusting the temperature of the cooling liquid to enable the temperature of the cooling liquid to reach a preset temperature of 58 ℃, and providing a stable cooling environment for the high-temperature pulsating heat pipe 21.
(4) The high-temperature heating furnace 20 is adjusted to a low-power heating state for warming up, because the carbon silicon rods are easily damaged by the excessively high heating speed of the high-temperature heating furnace 20 in the low-temperature state; in the warming-up process, the thermocouple, the RTD temperature sensor and the measurement and control system are debugged to ensure the accuracy of data; when the warm-up of the high-temperature heating furnace 20 is completed, the next step is performed.
(5) Increasing the heating power of the high-temperature heating furnace 20, adjusting the target temperature of the high-temperature heating furnace 20 to 850 ℃ and raising the temperature; after the temperature in the high-temperature heating furnace 20 reaches 850 ℃, maintaining for twenty minutes, wherein the heat load of the high-temperature pulsating heat pipe 21 is kept constant in the process; the experimental data were recorded before proceeding to the next step.
(6) Adjusting the target temperature of the high-temperature heating furnace 20 to 900 ℃ for heating; after the temperature in the high-temperature heating furnace 20 reaches 900 ℃, the temperature is maintained for twenty minutes, and in the process, the heat load of the high-temperature pulsating heat pipe 21 is kept constant. The experimental data were recorded and the next step was performed. Repeating the heating process, respectively heating the temperature in the high-temperature heating furnace 20 to 950 ℃, 1000 ℃, 1050 ℃ and 1100 ℃, testing the heat transfer performance of the high-temperature pulsating heat pipe 21 under different heating powers, recording experimental data, and carrying out the next step.
(7) And (3) closing the high-temperature heating furnace 20, reducing the temperature of the constant-temperature liquid tank 26, entering a cooling process, and ending the experiment when the cooling process is ended.
(8) Calculating the thermal load of the high-temperature pulsating heat pipe 21, wherein the heating power can be obtained by the following formula:
Qe＝CpqmΔT+q；
ΔT＝T1-T2；
in the formula: qeThe heat load (W) of the high-temperature pulsating heat pipe, q is the heat leakage (W)mThe mass flow (kg/s) of the cooling liquid measured by the flowmeter, T1Temperature (K) measured by RTD temperature sensor at tee joint of liquid outlet2The temperature (K) measured by RTD temperature sensors at the three-way position of the liquid inlet, the delta T is the temperature difference (K) at the inlet and the outlet of the cooling liquid, and CpThe specific heat capacity of water (J/(kg. K)) at the operating temperature, (T)1+T2) The operating temperature (K) is/2.
(9) Calculating heat leakage
The average temperature inside and outside the heat preservation layer is measured through the reading of the thermocouples arranged inside and outside the heat preservation layer to obtain the heat leakage, and the heat leakage can be obtained by the following formula:
in the formula: q is heat leakage (W), k is heat insulation layer materialThermal coefficient (W/(m.K)), and A is the area of the insulating layer (m)2)，ΔTlThe temperature difference (K) between the inside and the outside of the heat-insulating layer, and L is the thickness (m) of the heat-insulating layer.
The proportion of heat leakage to the heating power of the high-temperature pulsating heat pipe 21 is less than 10 percent, and the following formula is satisfied:
if the result obtained by calculation
The flow rate of the cooling liquid needs to be increased or the thickness of the heat-insulating material needs to be increased, and the experiment is performed again and the result is calculated to ensure that the proportion of the heat leakage to the heating power of the high-temperature pulsating heat pipe 21 is less than 10%.
(10) Calculating the thermal resistance of the high-temperature pulsating heat pipe 21, wherein the thermal resistance can be obtained by the following formula:
in the formula: r is the thermal resistance (K/W) of the high-temperature pulsating heat pipe,
the average temperature (K) of the heating section when the high-temperature pulsating heat pipe stably operates,
the average temperature (K) and Q of the condensation section when the high-temperature pulsating heat pipe stably operateseIs the heat load (W) of the high-temperature pulsating heat pipe.
FIG. 6 is a temperature chart showing the start of the pulsating heat pipe 21 and the temperature of the high temperature heating furnace 20 at 850 ℃. As can be seen from fig. 6, the high temperature heating furnace 20 was warmed up after 2700 seconds, the heating phase was started, the temperature rising rate was increased, when the temperature of the heating section 34 reaches 790 ℃, the temperature of the heating section 34 and the temperature of the heat insulation section 33 sharply decrease, the temperature of the condensation section 32 sharply increases, the high-temperature pulsating heat pipe 21 is started, the temperature of the high-temperature heating furnace 20 does not reach the preset temperature of 850 ℃, the power of the heating furnace is in an increasing stage, the heat load of the high-temperature pulsating heat pipe 21 cannot maintain stable pulsating motion, the phenomenon that the part of the elbow of the high-temperature pulsating heat pipe 21 stops working appears in 3300 seconds, and the temperature rise of the first thermocouple 1, the second thermocouple 2, the third thermocouple 3 and the fourth thermocouple 4 and the temperature drop of the thirteenth thermocouple 13, the fourteen thermocouple 14, the fifteenth thermocouple 15 and the sixteenth thermocouple 16 are measured, so that the pulsation of the root canal is weakened. The temperature of the fifth thermocouple 5 and the sixth thermocouple 6 is measured to be stable, and the corresponding cold end temperature has no sharp change, which indicates that the two pipes work normally. With the continuous temperature rise of the heating furnace, the high-temperature pulsating heat pipe 21 is started for the second time, and reaches the preset temperature in 3900 seconds, so that the high-temperature pulsating heat pipe 21 starts to work stably.
FIG. 7 is a temperature profile of the high temperature furnace 20 at stages of 900 deg.C, 950 deg.C and 1000 deg.C, respectively. As can be seen from fig. 7, when the furnace temperature of the high temperature heating furnace 20 is at the stages of 900 ℃ and 950 ℃, the high temperature pulsating heat pipe 21 operates relatively stably, the delamination phenomenon of the heat insulating section 33 is small, and at this time, the temperature of the heating section 34 rises as the furnace temperature increases, and at the same time, the temperature of the condensing section 32 rises, the temperature difference at the cold end and the hot end decreases, the thermal load increases, and the thermal resistance decreases. When the left elbow condensation section 32 is weakened in layering, the right elbow condensation section 32 is still layered, and the temperature difference between the seventeen thermocouple 17 and the eighteen thermocouple 18 is measured to be large, because the high-temperature pulsating heat pipe 21 has the phenomenon of single elbow heat transfer during stable operation, and the temperature of the nineteen thermocouple 19 is measured to be stable. When the temperature of the high-temperature heating furnace 20 is at a stage of 1000 ℃, the temperature of the heating section 34 begins to fluctuate, the heat insulation section 33 is layered, the thirteen thermocouple 13 and the fourteen thermocouple 14 of the left elbow generate violent fluctuation and show opposite change trends, the temperature of the nineteen thermocouple 19 is measured to rapidly rise, and at the moment, the violent fluctuation has the tendency of generating circulation.
Fig. 8 is a temperature profile of the high temperature heating furnace 20 at stages of 1050 ℃ and 1100 ℃. As can be seen from fig. 8, when the furnace temperature of the high temperature heating furnace 20 is 1050 ℃, the temperature of the seventh thermocouple 7 and the eleventh thermocouple 11 is decreased, the temperature of the eighth thermocouple 8 and the twelfth thermocouple 12 is increased rapidly, the ninth thermocouple 9 and the tenth thermocouple 10 are kept at higher temperatures, the temperature of the eighth thermocouple 8 and the twelfth thermocouple 12 is higher than the temperature of the seventh thermocouple 7 and the eleventh thermocouple 11, and meanwhile, the temperature of the nineteen thermocouple 19 is increased rapidly, the adiabatic section 33 is layered obviously, the temperature of the condensation section 32 corresponding to the adiabatic section has the same variation trend, a good and stable circulation state is formed, and the heat transfer effect is enhanced. When the furnace temperature of the high temperature heating furnace 20 is 1100 ℃, the temperature of each thermocouple fluctuates and the temperature rises with respect to the temperature at the stage of 1050 ℃, and the circulation state fluctuates.
Fig. 9 is a temperature profile of the high temperature heating furnace 20 in the stages of 1150 ℃ and 1200 ℃. As can be seen from fig. 9, when the furnace temperature of the high-temperature heating furnace 20 is 1150 ℃, it is measured that the temperatures of the seventh thermocouple 7 and the eleventh thermocouple 11 rapidly rise, the temperature of the eighteen thermocouple 18 rapidly falls, the temperatures of the thirteenth thermocouple 13 and the fourteenth thermocouple 14 rise, the temperature of the nineteen thermocouple 19 rapidly falls, the temperature fluctuation of the heating section 34 disappears, the working state tends to be stable, the unidirectional circulation disappears at this time, and the pulsating state is restored again. When the temperature of the high-temperature heating furnace 20 is 1200 ℃, the measured temperature of the seventh thermocouple 7 and the eleventh thermocouple 11 fluctuates sharply, the temperature of the eighteen thermocouple 18 rises, the high-temperature pulsating heat pipe 21 is unstable in operation, and the performance is deteriorated.
Fig. 10 is a graph showing the temperature difference between the cold end and the hot end of the high-temperature pulsating heat pipe 21 as a function of power. As can be seen from fig. 10, the temperature difference between the cold and hot ends of the high-temperature pulsating heat pipe 21 decreases and then increases as the thermal load increases, and the minimum value occurs when the heating power of the high-temperature pulsating heat pipe 21 is 3306.4W (the furnace temperature is 1050 ℃).
Fig. 11 is a graph of the thermal resistance of the high temperature pulsating heat pipe 21 as a function of power. As can be seen from fig. 11, the thermal resistance of the high-temperature pulsating heat pipe 21 decreases first and then increases as the heating power increases, and the minimum value occurs when the thermal load of the high-temperature pulsating heat pipe 21 is 3306.4W (furnace temperature 1050 ℃).
As can be seen from fig. 6 to 9, the high-temperature pulsating heat pipe 21 in the present embodiment has the capability of operating in a high-temperature environment exceeding 500 ℃. As can be seen from fig. 10-11, the lower the thermal resistance of the high temperature pulsating heat pipe 21, the better the performance.
As can be seen from fig. 6 to 11, the experimental data of the high-temperature pulsating heat pipe 21 under different working conditions can be accurately measured by using the whole set of test system, so that the test system in this embodiment meets the test requirements of the high-temperature pulsating heat pipe 21 under the high-temperature environment.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (7)
1. The testing method for the high-temperature pulsating heat pipe of the liquid metal is characterized in that the high-temperature pulsating heat pipe (21) comprises a three-way liquid filling port (30) and a stainless steel pipe array (31) which integrates a heating section (34), a heat insulation section (33) and a condensation section (32), two horizontal through ports of the three-way liquid filling port (30) are connected with two ports of the stainless steel pipe array (31), a working medium in the stainless steel pipe array (31) is the liquid metal, the liquid metal is one of sodium-potassium alloy, metal sodium, metal potassium, metal cesium or metal rubidium or a combination form of more than one of the liquid metal, and the mass fraction of potassium in the sodium-potassium alloy is 25% -75%;
the liquid filling rate of the high-temperature pulsating heat pipe (21) is 10-90 percent;
the testing method is used for measuring the heat transfer performance of the high-temperature pulsating heat pipe, and the testing method is measured through a testing system which comprises a high-temperature heating furnace (20) connected with the high-temperature pulsating heat pipe (21), a cooling liquid block (22), a high-pressure pump (27), a constant-temperature liquid tank (26), a flowmeter (25), a filter (28), a cooling liquid valve (29) and a measurement and control system, wherein the measurement and control system is in signal connection with the equipment;
the constant temperature liquid tank (26) is connected with one side of the high-pressure pump (27), the other side of the high-pressure pump (27) is connected with one side of the filter (28), the other side of the filter (28) is connected with one side of the cooling liquid valve (29), the other side of the cooling liquid valve (29) is connected with one side of the cooling liquid block (22) through a liquid inlet tee joint (23), the other side of the cooling liquid block (22) is connected with one side of the flowmeter (25) through a liquid outlet tee joint (24), the other side of the flowmeter (25) is connected with the constant-temperature liquid tank (26), all the devices form a circulating connection loop, the cooling liquid discharged from the constant-temperature liquid tank (26) flows along the anticlockwise direction and finally flows back into the constant-temperature liquid tank (26), and the cooling liquid realizes the circulating reciprocating flow through the high-pressure pump (27); a channel matched with the outer diameter of the high-temperature pulsating heat pipe (21) is arranged on the front side of the outer part of the cooling liquid block (22), the channel is connected with a condensation section (32) of the high-temperature pulsating heat pipe (21), a heat insulation section (33) of the high-temperature pulsating heat pipe (21) is connected with the high-temperature heating furnace (20), and a heating section (34) of the high-temperature pulsating heat pipe (21) is placed in the high-temperature heating furnace (20);
the test method is as follows: starting a high-pressure pump (27) to start circulation of the cooling liquid, adjusting the opening of a cooling liquid valve (29) and reading data of a flow meter (25) to adjust the flow rate of the cooling liquid, and filtering the cooling liquid through a filter (28) to remove impurities; starting a constant-temperature liquid tank (26), adjusting the temperature of the cooling liquid and providing a stable cooling environment for the high-temperature pulsating heat pipe (21); the high-temperature heating furnace (20) is adjusted to a low-power heating state for warming up, and in the warming up process, a thermocouple, an RTD temperature sensor and a measurement and control system are debugged to ensure the accuracy of data; the heating temperature, the heating speed, the heating power and the inclination angle of the high-temperature pulsating heat pipe (21) are controlled and adjusted by adjusting the parameter setting of the high-temperature heating furnace (20), the parameters of a multi-section heating process are set by adjusting the heating program of the high-temperature heating furnace (20), the heating speed and the target furnace temperature are adjusted and heat preservation is carried out, the heating power is kept constant after the high-temperature pulsating heat pipe (21) works stably, and experimental data are recorded; closing the high-temperature heating furnace (20), reducing the temperature of the constant-temperature liquid tank (26), entering a cooling process, and ending the experiment when the cooling process is ended;
the periphery of the high-temperature pulsating heat pipe (21) and the periphery of the cooling liquid block (22) are integrally wrapped by a heat insulation layer, the heat insulation layer is made of high-temperature-resistant heat insulation materials, and at least 4 thermocouples are arranged inside and outside the heat insulation layer and used for measuring the temperature of the inner wall and the outer wall of the heat insulation layer to obtain heat leakage.
2. The testing method according to claim 1, wherein the tubing of the high temperature pulsating heat pipe (21) is one of stainless steel, nickel based alloy or Inconel nickel based alloy, or a combination of more than one; the wall thickness of the high-temperature pulsating heat pipe (21) is 0.5-3 mm, and the inner diameter of the high-temperature pulsating heat pipe meets the following formula:
in the formula: deThe inner diameter (m) of the high-temperature pulsating heat pipe, D is the starting critical pipe diameter of the pulsating heat pipe, phi is the liquid filling rate (%),
is the percentage (%) of the total pipe volume occupied by the liquid after heat addition, rhoL,0For the density of the liquid at the operating temperature before the addition of heat (kg/m)3)，ρL,avIs the average density (kg/m) of the liquid working medium after heat addition3) U is the rising speed (m/s) of the vapor bubble relative to the liquid, hcIs the latent heat of vaporization (J/kg) of working medium at cold end temperature, q is input power (J/s), and pgIs latent heat ratio (%).
3. The test method according to claim 1, characterized in that the temperature of the cooling liquid discharged from the thermostatic liquid bath (26) ranges from 5 ℃ to 300 ℃.
4. The test method according to claim 1, wherein an RTD temperature sensor is connected to each of the inlet tee (23) and the outlet tee (24), and the RTD temperature sensor extends into the center of the cooling liquid pipeline.
5. The test method according to claim 1, wherein the high temperature heating furnace (20) is a sealed box structure, the top of the box structure is provided with a hearth upper cover, the hearth upper cover is provided with a stepped hole (35), and a middle through hole of the stepped hole (35) is connected with the high temperature pulsating heat pipe (21); a side gap formed between the stepped hole (35) and the high-temperature pulsating heat pipe (21) vertical to the upper cover of the hearth is filled and sealed by using a high-temperature-resistant heat-insulating material; the flange plates are welded at the center positions of two sides of the furnace body of the high-temperature heating furnace (20), and angle adjusting devices composed of gear transmission mechanisms are mounted on the flange plates and used for adjusting the integral inclination angle of the high-temperature heating furnace (20), and the range of the inclination angle is 0-180 degrees.
6. The test method according to claim 1, wherein the heating section (34), the heat insulation section (33) and the condensation section (32) of the high-temperature pulsating heat pipe (21) are respectively provided with at least one thermocouple, and the transverse pipe above the condensation section (32) of the high-temperature pulsating heat pipe (21) is provided with at least one thermocouple; the method is used for obtaining the temperature change of the high-temperature pulsating heat pipe, analyzing the heat transfer characteristic of the high-temperature pulsating heat pipe and calculating the thermal resistance of the high-temperature pulsating heat pipe.
7. The test method according to claim 6, wherein the thermal resistance of the high temperature pulsating heat pipe (21) is determined by the following formula:
in the formula: r is the thermal resistance (K/W) of the high-temperature pulsating heat pipe,
the average temperature (K) of the heating section when the high-temperature pulsating heat pipe stably operates,
the average temperature (K) and Q of the condensation section when the high-temperature pulsating heat pipe stably operateseHeating power (W) of the high-temperature pulsating heat pipe;
the heating power of the high-temperature pulsating heat pipe (21) can be obtained by the following formula:
Qe＝CpqmΔT+q；
ΔT＝T1-T2；
in the formula: qeHeating power (W) for the high-temperature pulsating heat pipe, q is heat leakage (W), and q ismThe mass flow (kg/s) of the cooling liquid measured by the flowmeter, T1Temperature (K) measured by RTD temperature sensor at tee joint of liquid outlet2The temperature (K) measured by RTD temperature sensors at the three-way position of the liquid inlet, the delta T is the temperature difference (K) at the inlet and the outlet of the cooling liquid, and CpThe specific heat capacity of water (J/(kg. K)) at the operating temperature, (T)1+T2) The operating temperature (K) is/2;
the heat leakage can be determined by the following formula:
in the formula: q is heat leakage (W), K is the thermal conductivity (W/(m.K)) of the material of the insulating layer, A is the area (m) of the insulating layer2)，ΔTlThe temperature difference (K) between the inside and the outside of the heat-insulating layer, and L is the thickness (m) of the heat-insulating layer;
the proportion of the heat leakage to the heating power of the high-temperature pulsating heat pipe (21) is less than 10 percent, and the following formula is satisfied:
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| US17/631,262 US20220299458A1 (en) | 2019-08-20 | 2020-06-29 | Liquid metal high-temperature oscillating heat pipe and testing method |
| PCT/CN2020/098716 WO2021031699A1 (en) | 2019-08-20 | 2020-06-29 | Liquid metal high-temperature pulsating heat pipe and testing method |
| JP2021568906A JP7300202B2 (en) | 2019-08-20 | 2020-06-29 | Test system and test method used to measure the heat transfer performance of liquid metal high temperature self-oscillating heat pipes |
| KR1020217039600A KR102583698B1 (en) | 2019-08-20 | 2020-06-29 | Liquid metal high temperature vibrating heat pipe and test method |
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| CN112964747B (en) * | 2021-03-10 | 2022-04-22 | 北京科技大学 | Gas condensation visualization and heat exchange characteristic detection device and method |
| CN113740378A (en) * | 2021-09-15 | 2021-12-03 | 山东多星电器有限公司 | Method for testing heat energy conversion efficiency of electric heating tube |
| CN114593621A (en) * | 2022-02-25 | 2022-06-07 | 上海格熵航天科技有限公司 | Design method for working medium filling amount and gas reservoir volume of low-temperature loop heat pipe |
| CN217404195U (en) * | 2022-03-11 | 2022-09-09 | 阳光电源股份有限公司 | Performance detection device of heat pipe radiator |
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| TWI274859B (en) * | 2005-08-12 | 2007-03-01 | Hon Hai Prec Ind Co Ltd | Apparatus for performance testing of heat pipe |
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