CN112304134B - Rotational symmetry accumulated temperature difference vibration loop heat pipe - Google Patents
Rotational symmetry accumulated temperature difference vibration loop heat pipe Download PDFInfo
- Publication number
- CN112304134B CN112304134B CN201910692882.5A CN201910692882A CN112304134B CN 112304134 B CN112304134 B CN 112304134B CN 201910692882 A CN201910692882 A CN 201910692882A CN 112304134 B CN112304134 B CN 112304134B
- Authority
- CN
- China
- Prior art keywords
- pipe
- heating
- tube
- header
- heat source
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- 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
- F28D15/0266—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 separate evaporating and condensing chambers connected by at least one conduit; Loop-type heat pipes; with multiple or common evaporating or condensing chambers
-
- 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
- F28D15/06—Control arrangements therefor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28G—CLEANING OF INTERNAL OR EXTERNAL SURFACES OF HEAT-EXCHANGE OR HEAT-TRANSFER CONDUITS, e.g. WATER TUBES OR BOILERS
- F28G7/00—Cleaning by vibration or pressure waves
Abstract
The invention provides a loop heat pipe, which comprises a middle evaporating pipe, a left header, a right header and a pipe group, wherein the pipe group comprises a left pipe group and a right pipe group, the left pipe group is communicated with the left header and the middle evaporating pipe, the right pipe group is communicated with the right header and the middle evaporating pipe, so that the middle evaporating pipe, the left header, the right header and the pipe group form heating fluid closed circulation, and a heat source is arranged in the middle evaporating pipe; the temperature sensing element is arranged in the loop heat pipe and is used for detecting the temperature in the loop heat pipe, the temperature sensing element is in data connection with the controller, the controller extracts temperature data according to time sequence, the temperature difference or the accumulation of temperature difference change is obtained through comparison of the temperature data in adjacent time periods, and when the temperature difference or the accumulation of temperature difference change is lower than a threshold value, the controller controls the heat source to stop heating or continue heating. The loop heat pipe can judge whether the state is stable or not according to the internal temperature difference or the accumulated temperature difference, and then intelligently control the heating of the heat source according to the internal pressure difference, so that the fluid in the loop heat pipe can vibrate frequently, and the scale removal and heating effects are good.
Description
Technical Field
The invention relates to a loop heat pipe, in particular to an elastic vibration descaling loop heat pipe.
Background
The heat pipe technology is a heat transfer element called a "heat pipe" invented by George Grover (Los Alamos) national laboratory in the United states of Amersham (1963), which fully utilizes the heat conduction principle and the rapid heat transfer property of a phase change medium, and rapidly transfers the heat of a heating object to the outside of a heat source through the heat pipe, and the heat conduction capability of the heat pipe exceeds that of any known metal.
The heat pipe technology is widely applied to the industries of aerospace, military industry and the like before, since the heat pipe technology is introduced into the radiator manufacturing industry, the design thought of the traditional radiator is changed, a single radiating mode of obtaining a better radiating effect by simply relying on a high-air-volume motor is eliminated, the heat pipe technology is adopted to enable the radiator to obtain a satisfactory heat exchanging effect, and a new world of the radiating industry is opened up. At present, the heat pipe is widely applied to various heat exchange equipment, including the nuclear power field, such as the utilization of the waste heat of nuclear power, and the like.
Current heat pipes, particularly multi-circuit loop heat pipes such as those described in fig. 1, include dual headers, one header evaporating and one header condensing, thereby forming a vibratory descaling heat pipe. Thereby improving the heat exchange efficiency of the heat pipe and reducing scaling. However, the heat exchange uniformity of the heat pipe is not enough, only one side is condensed, but the heat exchange amount is small, so that improvement is needed, and a heat pipe system with a novel structure is developed.
However, in applications it has been found that the continuous heating of the heat source results in a fluid forming stability of the internal electrical heating means, i.e. no or little fluid flow, or a stable flow, resulting in a substantial reduction of the vibration properties of the coil, thereby affecting the descaling of the coil and the efficiency of the heating.
In the prior application, only the data of the temperature, the pressure and the liquid level are controlled, the internal heating is considered to be in a sufficient state when certain data are reached, and the fluid flow state is also considered to be in a stable state, but the judgment mode can generate obvious errors along with the continuous operation of the heating device, so that the result is inaccurate.
This application is an improvement over previous projects that have been developed in common in multiple units.
Disclosure of Invention
The invention provides an elastic heat pipe with a novel structure aiming at the defect of elasticity in the prior art. The elastic heat pipe can improve descaling and heat exchange effects according to parameter detection.
In order to achieve the above purpose, the invention adopts the following technical scheme:
the loop heat pipe comprises a middle evaporating pipe, a left header, a right header and a pipe group, wherein the pipe group comprises a left pipe group and a right pipe group, the left pipe group is communicated with the left header and the middle evaporating pipe, the right pipe group is communicated with the right header and the middle evaporating pipe, so that the middle evaporating pipe, the left header, the right header and the pipe group form a heating fluid closed cycle, and a heat source is arranged in the middle evaporating pipe; the temperature sensing element is arranged in the loop heat pipe and is used for detecting the temperature in the loop heat pipe, the temperature sensing element is in data connection with the controller, the controller extracts temperature data according to time sequence, the temperature difference or the accumulation of temperature difference change is obtained through comparison of the temperature data in adjacent time periods, and when the temperature difference or the accumulation of temperature difference change is lower than a threshold value, the controller controls the heat source to stop heating or continue heating.
If the temperature in the previous period is T1, the temperature in the adjacent subsequent period is T2, and if T1< T2 is lower than the threshold value, the controller controls the heat source to stop heating; if T1> T2, below the threshold, the controller controls the heat source to heat.
Preferably, the temperature sensing elements are disposed at upper ends within the middle evaporator tube, the left header and the right header.
The invention has the following advantages:
1. the loop heat pipe can judge whether the state is stable or not according to the internal temperature difference or the accumulated temperature difference, and then intelligently control the heating of the heat source according to the internal pressure difference, so that the fluid in the loop heat pipe can vibrate frequently, and the scale removal and heating effects are good.
2. According to the invention, the heating efficiency can be further improved through the arrangement of pipe diameters and interval distribution of the pipe groups in the height direction.
3. The invention optimizes the optimal relation of the parameters of the loop heat pipe through a large number of experiments and numerical simulation, thereby realizing optimal heating efficiency.
4. The invention designs a layout diagram of a novel structure multi-loop heat pipe triangle, optimizes structural parameters of the layout, and can further improve heating efficiency through the layout.
Description of the drawings:
FIG. 1 is a top view of a loop heat pipe of the present invention.
Fig. 2 is a front view of a loop heat pipe of the present invention.
Fig. 3 is a front view of another embodiment of the loop heat pipe of the present invention.
FIG. 4 is a schematic diagram of the dimensional structure of the loop heat pipe of the present invention.
FIG. 5 is a schematic diagram of the layout of the loop heat pipe of the present invention in a circular section heater.
Fig. 6 is a control flow diagram.
In the figure: 1. tube group, left tube group 11, right tube group 12, 21, left header 22, right header 3, free end 4, free end 5, free end 6, free end 7, arc tube 8, middle evaporation tube 9, heat source 10 first tube orifice, 13 second tube orifice, left return tube 14, right return tube 15
Detailed Description
The following describes the embodiments of the present invention in detail with reference to the drawings.
Herein, "/" refers to division, "×", "x" refers to multiplication, unless otherwise specified.
As shown in fig. 1, a loop heat pipe includes a central evaporating pipe 8, a left header 21, a right header 22 and a pipe group 1, the pipe group 1 includes a left pipe group 11 and a right pipe group 12, the left pipe group 11 communicates with the left header 21 and the central evaporating pipe 8, the right pipe group 12 communicates with the right header 22 and the central evaporating pipe 8, so that the central evaporating pipe 8, the left header 21, the right header 22 and the pipe group 1 form a heating fluid closed cycle, the central evaporating pipe 8 is filled with a phase-change fluid, a heat source 9 is arranged in the central evaporating pipe 8, each pipe group 1 includes a plurality of arc-shaped pipes 7 in a circular arc shape, the ends of adjacent arc-shaped pipes 7 communicate, the plurality of arc-shaped pipes 7 form a series structure, and the ends of the arc-shaped pipes 7 form arc-shaped pipe free ends 3 to 6; the middle evaporation tube comprises a first tube orifice 10 and a second tube orifice 13, wherein the first tube orifice 10 is connected with the inlet of the left tube group 11, the second tube orifice 13 is connected with the inlet of the right tube group 12, the outlet of the left tube group 11 is connected with the left header 21, and the outlet of the right tube group 12 is connected with the right header 22; the first nozzle 10 and the second nozzle 13 are provided on opposite sides of the central evaporator tube 8.
Preferably, a left return pipe 14 is arranged between the left header 21 and the middle evaporation pipe 8, and a right return pipe 14 is arranged between the right header 22 and the middle evaporation pipe 8. Preferably, the return pipe is arranged at the bottom.
The fluid is heated and evaporated in the middle evaporation tube 8, flows along the arc tube bundles to the left and right headers 21, 22, and expands in volume after being heated to form steam, and the steam is much larger in volume than water, so that the formed steam can quickly impact flow in the coil. Because volume expansion and steam flow can induce the free end of the arc tube to vibrate, the free end of the heat exchange tube transmits the vibration to surrounding heat exchange fluid in the vibration process, and the fluids can generate disturbance among each other, so that the surrounding heat exchange fluid forms turbulence and damages a boundary layer, and the aim of enhancing heat transfer is fulfilled. The fluid flows back to the middle evaporating pipe through the return pipe after the left and right headers condense and release heat.
According to the invention, the prior art is improved, the condensing header and the tube groups are respectively arranged into two groups which are distributed left and right, so that the tube groups distributed on the left side and the right side can perform vibration heat exchange and scale removal, thereby enlarging the heat exchange vibration area, enabling the vibration to be more uniform, enabling the heat exchange effect to be more uniform, increasing the heat exchange area and strengthening the heat exchange and scale removal effects.
Preferably, the arc tubes of the left tube group are distributed by taking the axis of the left collecting tube as the center of a circle, and the arc tubes of the right tube group are distributed by taking the axis of the right collecting tube as the center of a circle. Through setting left and right collecting pipes as the circle centers, the distribution of the arc-shaped pipes can be better ensured, so that the vibration and the heating are uniform.
Preferably, the tube group is plural.
Preferably, the position of the right tube group (including the right header) is a position in which the left tube group (including the left header) is rotated 180 degrees (angle) along the axis of the middle evaporator tube. Through such setting, can make the arc pipe distribution of heat transfer more reasonable even, improve the heat transfer effect.
Preferably, the headers 8, 21, 22 are arranged in the height direction.
Preferably, the left tube group 21 and the right tube group 22 are staggered in the height direction, as shown in fig. 2. Through staggered distribution, vibration heat exchange and descaling can be performed at different heights, so that vibration is more uniform, and heat exchange and descaling effects are enhanced.
Preferably, the tube group 2 (e.g., the same side (left side or right side)) is provided in plural in the height direction of the middle evaporation tube 8, and the tube diameter of the tube group 2 (e.g., the same side (left side or right side)) is continuously made smaller from the top down direction.
Preferably, the tube diameters of the arc-shaped tubes of the tube group (e.g., the same side (left or right)) are continuously decreasing in an upward-downward direction of the middle evaporation tube 8.
Through the pipe diameter amplitude increase of the pipe group, more steam can be guaranteed to enter the left box body and the right box body through the upper portion, distribution of steam in all pipe groups is guaranteed to be even, heat transfer effect is further enhanced, the overall vibration effect is even, the heat transfer effect is increased, and heat transfer effect and descaling effect are further improved. Experiments show that better heat exchange effect and descaling effect can be obtained by adopting the structural design.
Preferably, the same side (left side or right side) tube group is provided in plural along the height direction of the middle evaporation tube 8, and the pitch of adjacent tube groups on the same side (left side or right side) is increased from the top down.
Preferably, the spacing between the tube groups on the same side (left or right) is increased in the height direction of the first header.
Through the increase of the interval amplitude of the pipe groups, more steam can be ensured to enter the left and right headers through the upper parts, the distribution of the steam in all the pipe groups is ensured to be uniform, the heat transfer effect is further enhanced, the overall vibration effect is uniform, the heat transfer effect is increased, and the heat transfer effect and the descaling effect are further improved. Experiments show that better heat exchange effect and descaling effect can be obtained by adopting the structural design.
In the experiments, it was found that the tube diameters, distances, and tube diameters of the left header 21, the right header 22, the middle evaporation tube 8, and the arc-shaped tube can have an influence on the heat exchange efficiency and uniformity. If the distance between the headers is too large, the heat exchange efficiency is too poor, the distance between the arc-shaped pipes is too small, the arc-shaped pipes are distributed too densely, the heat exchange efficiency is also affected, the pipe diameters of the headers and the heat exchange pipes affect the volume of the contained liquid or steam, and vibration of the free ends is affected, so that heat exchange is affected. The tube diameters, distances and arc-shaped tube diameters of the left header 21, the right header 22 and the middle evaporation tube 8 have a certain relationship.
The invention relates to an optimal size relation which is summarized by numerical simulation and test data of a plurality of heat pipes with different sizes. From the maximum heat exchange amount in the heat exchange effect, nearly 200 forms are calculated. The dimensional relationships are as follows:
the distance between the center of the middle evaporation tube 8 and the center of the left header 21 is equal to the distance between the center of the middle evaporation tube 8 and the center of the right header 21, L, the tube diameter of the left header 21, the tube diameter of the middle evaporation tube 8, the radius of the right header 22 is R, the radius of the axis of the innermost arced tube in the arced tube is R1, and the radius of the axis of the outermost arced tube is R2, then the following requirements are satisfied:
R1/R2＝a*(R/L) 2 -b (R/L) +c; wherein a, b, c are parameters, wherein 4.834<a<4.835，1.390<b<1.391，0.5585<c<0.5590; preferably, a=4.8344, b=1.3906, c= 0.5587.
Preferably, 34< R <61mm;114< L <191mm;69< R1<121mm,119< R2<201mm.
Preferably, the number of arcuate tubes of the tube set is 3-5, preferably 3 or 4.
Preferably, 0.57< R1/R2<0.61;0.3< R/L <0.32.
Preferably, 0.583< R1/R2<0.60;0.304< R/L <0.316.
Preferably, the radius of the arced tube is preferably 10-40mm; preferably 15 to 35mm, and more preferably 20 to 30mm.
Preferably, the centers of the left header 21, the right header 22 and the middle evaporation tube 8 are on the same straight line.
Preferably, the arc between the ends of the free ends 3, 4 is 95-130 degrees, preferably 120 degrees, centered on the central axis of the left header. The free ends 5, 6 and the free ends 3, 4 have the same radian. By the design of the preferable included angle, the vibration of the free end is optimized, so that the heating efficiency is optimized.
Preferably, the loop heat pipe can be used as an immersed heat exchange component, immersed in fluid to heat the fluid, for example, the loop heat pipe can be used as an air radiator heating component and also can be used as a water heater heating component.
The heating power of the heat source is preferably 1000 to 2000W, more preferably 1500W.
Preferably, the box body is of a circular section, and a plurality of electric heating devices are arranged, wherein one electric heating device is arranged at the center of the circle center of the circular section, and the other electric heating devices are distributed around the circle center of the circular section.
Preferably, the tube bundle of the tube group 1 is an elastic tube bundle.
By providing the tube bundle of the tube group 1 with an elastic tube bundle, the heat exchange coefficient can be further improved.
Further preferably, the heat source is an electrical heating rod.
The number of the tube groups 1 is plural, and the plurality of tube groups 1 are in a parallel structure.
It has been found in research and practice that the heating of a constant power stable heat source results in a fluid forming stability of the inner loop heat pipe, i.e. no flow or little flow or a steady flow, resulting in a greatly reduced vibration performance of the pipe stack 1, thereby affecting the descaling and heating efficiency of the pipe stack 1. There is a need for improvements in the loop heat pipe described above as follows.
In the applicant's prior application, a periodic heating method is proposed, and vibration of the tube set is continuously promoted by the periodic heating method, so that heating efficiency and descaling effect are improved. However, by adjusting the vibration of the tube set by a fixed periodic variation, hysteresis may occur and the period may be too long or too short. Therefore, the invention improves the prior application and intelligently controls the vibration, so that the fluid in the interior can vibrate frequently, and the scale removal and heating effects are very good.
Aiming at the defects in the prior research technology, the invention provides a novel electric heating loop heat pipe capable of intelligently controlling vibration. The heat pipe can improve heating efficiency, thereby realizing good descaling and heating effects.
1. Autonomous adjustment of vibration based on pressure differential
Preferably, a pressure sensing element is arranged in the electric heating device and is used for detecting the pressure in the electric heating device, the pressure sensing element is in data connection with a controller, the controller extracts pressure data according to time sequence, and the pressure difference or the accumulation of pressure difference change is obtained through comparison of the pressure data of adjacent time periods, and when the pressure difference or the accumulation of pressure difference change is lower than a threshold value, the controller controls a heat source to stop heating or continue heating.
The pressure difference or the accumulated pressure difference in the front and rear time periods detected by the pressure sensor can be used for judging that the evaporation of the fluid in the interior is basically saturated and the volume of the fluid in the interior is basically not changed greatly, and in such a case, the fluid in the interior is relatively stable, and the vibration of the tube bundle at this time is poor, so that the tube bundle needs to be adjusted to vibrate, and the heating is stopped. So that the fluid undergoes a volume reduction to thereby effect vibration. When the pressure difference is reduced to a certain extent, the internal fluid starts to enter a stable state again, and heating is needed to lead the fluid to be vaporized and expanded again, so that a starting heat source is needed to heat.
The steady state of the fluid is judged according to the pressure difference or the accumulation of the pressure difference change, so that the result is more accurate, and the problem of error increase caused by aging due to the problem of operation time is avoided.
Preferably, if the pressure in the preceding period is P1, the pressure in the adjacent following period is P2, and if P1< P2 is lower than the threshold value, the controller controls the heat source to stop heating; if P1> P2, then below the threshold, the controller controls the heat source to heat.
The current heating state or non-heating state of the heat source is determined through the judgment of the pressure, so that the running state of the heat source is determined according to different conditions.
Preferably, if the pressure in the preceding period is P1 and the pressure in the adjacent following period is P2, if p1=p2, the heating is judged according to the following condition:
if P1 is larger than the pressure of the first data, when the pressure is lower than the threshold value, the controller controls the heat source to stop heating; wherein the first data is greater than the pressure of the phase-change fluid after the phase change has occurred; preferably the first data is the pressure at which the phase change fluid is substantially phase-changed;
if P1 is smaller than or equal to the pressure of the second data, when the pressure is lower than the threshold value, the controller controls the heat source to continue heating, wherein the pressure of the second data is smaller than or equal to the pressure of the phase-change fluid, and the phase change does not occur.
The first data is pressure data of a fully heated state, and the second data is pressure data of no heating or just beginning heating. The judgment of the pressure is also used for determining whether the current heat source is in a heating state or a non-heating state, so that the operation state of the heat source is determined according to different conditions.
Preferably, the number of the pressure sensing elements is n, and the pressure P in the current time period is calculated in sequence i And the pressure Q in the previous period i-1 Difference D of (2) i ＝P i -Q i-1 And for n pressure differences D i Performing arithmetic cumulative summation
When the value of Y is lower than the set threshold, the controller controls the heat source to stop heating or to continue heating.
Preferably, Y >0, and below the threshold, the controller controls the heat source to stop heating; if Y <0, the controller controls the heat source to heat when the value is lower than the threshold value.
The current heating state or non-heating state of the heat source is determined through the judgment of the pressure, so that the running state of the heat source is determined according to different conditions.
Preferably, if y=0, the heating is judged according to the following condition:
if P i If the arithmetic mean of the data is greater than the pressure of the first data, the controller controls the heat source to stop heating when the arithmetic mean is lower than the threshold value; wherein the first data is greater than the pressure of the phase-change fluid after the phase change has occurred; preferably a pressure at which the phase-change fluid is substantially phase-changed;
if P i When the arithmetic mean of the second data is smaller than the pressure of the second data, and the second data is smaller than or equal to the pressure of the phase-change fluid, the controller controls the heat source to continue heating when the arithmetic mean of the second data is smaller than or equal to the pressure of the second data and the pressure of the second data is smaller than the thresholdGenerating phase-change pressure.
The first data is pressure data of a fully heated state, and the second data is pressure data of no heating or just beginning heating. The judgment of the pressure is also used for determining whether the current heat source is in a heating state or a non-heating state, so that the operation state of the heat source is determined according to different conditions.
Preferably, the period of time for measuring the pressure is 1 to 10 minutes, preferably 3 to 6 minutes, and more preferably 4 minutes.
Preferably, the threshold is 100-1000Pa, preferably 500Pa.
Preferably, the pressure value may be an average pressure value over a period of time. The pressure at a certain point in the time period may also be made. For example, preferably both are pressures at the end of the time period.
Preferably, the pressure sensing element is arranged in the middle evaporator tube and/or in the left header and/or in the right header.
Preferably, the pressure sensing elements are disposed within the central evaporator tube, the left header and the right header. The average pressure value of the plurality of tube boxes can be selected as the adjustment data at this time.
Preferably, the pressure sensing element is disposed at the free end. Through setting up at the free end, can perceive the pressure variation of free end to realize better control and regulation.
2. Autonomously adjusting vibration based on temperature
Preferably, a temperature sensing element is arranged in the electric heating device and is used for detecting the temperature in the electric heating device, the temperature sensing element is in data connection with a controller, the controller extracts temperature data according to time sequence, and the temperature difference or the accumulation of the temperature difference change is obtained through comparison of the temperature data of adjacent time periods, and when the temperature difference or the accumulation of the temperature difference change is lower than a threshold value, the controller controls a heat source to stop heating or continue heating.
The temperature difference between the front and rear time periods or the cumulative temperature difference detected by the temperature sensor can determine that the evaporation of the fluid in the interior is substantially saturated by the temperature difference, and the volume of the fluid in the interior is not substantially changed. So that the fluid undergoes a volume reduction to thereby effect vibration. When the temperature difference is reduced to a certain extent, the internal fluid starts to enter a stable state again, and heating is needed to lead the fluid to be vaporized and expanded again, so that a starting heat source is needed to heat.
The steady state of the fluid is judged according to the temperature difference or the accumulation of the temperature difference change, so that the result is more accurate, and the problem of error increase caused by aging due to the problem of operation time is avoided.
Preferably, if the temperature of the preceding time period is T1, the temperature of the adjacent following time period is T2, and if T1< T2 is lower than the threshold value, the controller controls the heat source to stop heating; if T1> T2, below the threshold, the controller controls the heat source to heat.
The current heating state or non-heating state of the heat source is determined through the temperature judgment in sequence, so that the running state of the heat source is determined according to different conditions.
Preferably, if the temperature in the preceding period is T1 and the temperature in the adjacent following period is T2, if t1=t2, the heating is judged according to the following condition:
if T1 is greater than the temperature of the first data, when the temperature is lower than the threshold value, the controller controls the heat source to stop heating; wherein the first data is greater than a temperature of the phase-change fluid after the phase change has occurred; preferably the first data is the temperature at which the phase change fluid is sufficiently phase-changed;
if T1 is less than or equal to the temperature of the second data, and is lower than the threshold value, the controller controls the heat source to continue heating, wherein the second data is less than or equal to the temperature at which the phase change fluid does not undergo phase change.
The first data is temperature data of a fully heated state, and the second data is temperature data of no heating or just starting heating. The above-mentioned judgment of the temperature also determines whether the current heat source is in a heating state or in a non-heating state, so as to determine the operation state of the heat source according to different conditions.
Preferably, the number of the temperature sensing elements is n, and the temperature T in the current time period is calculated in sequence i And the previous time period temperature Q i-1 Difference D of (2) i ＝T i -Q i-1 And for n temperature differences D i Performing arithmetic cumulative summation
When the value of Y is lower than the set threshold, the controller controls the heat source to stop heating or to continue heating.
Preferably, Y >0, and below the threshold, the controller controls the heat source to stop heating; if Y <0, the controller controls the heat source to heat when the value is lower than the threshold value.
The current heating state or non-heating state of the heat source is determined through the temperature judgment in sequence, so that the running state of the heat source is determined according to different conditions.
Preferably, if y=0, the heating is judged according to the following condition:
if T i When the arithmetic mean of the first data is larger than the temperature of the first data and is lower than the threshold value, the controller controls the heat source to stop heating; wherein the first data is greater than a temperature of the phase-change fluid after the phase change has occurred; preferably a temperature at which the phase change fluid is substantially phase-changed;
if T i And when the arithmetic mean of the second data is smaller than the temperature of the second data, the controller controls the heat source to continue heating when the arithmetic mean of the second data is smaller than the threshold, wherein the second data is smaller than or equal to the temperature at which the phase change fluid does not generate phase change.
The first data is temperature data of a fully heated state, and the second data is temperature data of no heating or just starting heating. The above-mentioned judgment of the temperature also determines whether the current heat source is in a heating state or in a non-heating state, so as to determine the operation state of the heat source according to different conditions.
Preferably, the period of time for measuring the temperature is 1 to 10 minutes, preferably 3 to 6 minutes, and more preferably 4 minutes.
Preferably, the threshold is 1-10 degrees celsius, preferably 4 degrees celsius.
Preferably, the temperature value may be an average temperature value over a period of time. The temperature at a certain point in the time period may be set. For example, the temperatures at the end of the time period are all preferred.
Preferably, the temperature sensing element is provided at the upper end in the middle evaporator tube and/or the left header and/or the right header.
Preferably, the temperature sensing elements are disposed at upper ends within the middle evaporator tube, the left header and the right header. The average temperature of the plurality of tube boxes can be selected as the adjustment data at this time.
Preferably, the temperature sensing element is disposed at the free end. Through setting up at the free end, can perceive the temperature variation of free end to realize better control and regulation.
3. Autonomous adjustment of vibration based on liquid level
Preferably, a liquid level sensing element is arranged in the middle evaporation tube and is used for detecting the liquid level of fluid in the middle evaporation tube, the liquid level sensing element is in data connection with a controller, the controller extracts liquid level data according to time sequence, the accumulation of liquid level difference or liquid level difference change of the liquid level data is obtained through comparison of the liquid level data of adjacent time periods, and when the liquid level difference or the liquid level difference change is lower than a threshold value, the controller controls a heat source to stop heating or continue heating.
The liquid level difference or the accumulated liquid level difference between the front and rear time detected by the liquid level sensor can be used for judging that the evaporation of the fluid in the interior is basically saturated and the volume of the fluid in the interior is basically not changed greatly, and in such a case, the fluid in the interior is relatively stable, and the vibration of the tube bundle at this time is poor, so that the tube bundle needs to be adjusted to vibrate, and the heating is stopped. So that the fluid undergoes a volume reduction to thereby effect vibration. When the level difference increases to a certain extent, the internal fluid starts to enter a stable state again, and heating is needed to lead the fluid to be vaporized and expanded again, so that a starting heat source is needed to heat.
The steady state of the fluid is judged according to the liquid level difference or the accumulation of the liquid level difference change, so that the result is more accurate, and the problem of error increase caused by aging due to the problem of operation time is avoided.
Preferably, if the liquid level in the preceding time period is L1, the liquid level in the adjacent following time period is L2, and if L1> L2, the controller controls the heat source to stop heating when it is lower than the threshold; if L1< L2, then below the threshold, the controller controls the heat source to heat.
The current state of heating or non-heating of the heat source is determined by judging the liquid level sequentially, so that the running state of the heat source is determined according to different conditions.
Preferably, if the liquid level in the preceding period is L1, the liquid level in the adjacent following period is L2, and if l1=l2, the heating is judged according to the following condition:
if L1 is smaller than the liquid level of the first data or L1 is 0, the controller controls the heat source to stop heating when the liquid level is lower than the threshold value; wherein the first data is greater than the liquid level of the phase-change fluid after the phase change; preferably the first data is a level at which the phase change fluid is substantially phase-changed;
if L1 is greater than or equal to the liquid level of the second data, and is lower than the threshold value, the controller controls the heat source to continue heating, wherein the second data is smaller than or equal to the liquid level of the phase-change fluid, and the phase change of the liquid does not occur.
The first data is the liquid level data of the fully heated state, including the liquid level of dry, and the second data is the liquid level data of the non-heating state or the heating state. The judgment of the liquid level is also used for determining whether the current heat source is in a heating state or a non-heating state, so that the operation state of the heat source is determined according to different conditions.
Preferably, the number of the liquid level sensing elements is n, and the liquid level L in the current time period is calculated in sequence i With the level Q of the previous period i-1 Difference D of (2) i ＝L i -Q i-1 And for n liquid level differences D i Performing arithmetic cumulative summation
When the value of Y is lower than the set threshold, the controller controls the heat source to stop heating or to continue heating.
Preferably, Y >0, and below the threshold, the controller controls the heat source to stop heating; if Y <0, the controller controls the heat source to heat when the value is lower than the threshold value.
The current state of heating or non-heating of the heat source is determined by judging the liquid level sequentially, so that the running state of the heat source is determined according to different conditions.
Preferably, if y=0, the heating is judged according to the following condition:
if L i If the arithmetic mean of the first data is less than the liquid level of the first data or 0, and if the arithmetic mean of the first data is less than the threshold value, the controller controls the heat source to stop heating; wherein the first data is greater than the liquid level of the phase-change fluid after the phase change; preferably a liquid level at which the phase-change fluid is substantially phase-changed;
if L i And when the arithmetic average of the second data is larger than the liquid level of the second data, and the arithmetic average of the second data is lower than the threshold, the controller controls the heat source to continue heating, wherein the second data is smaller than or equal to the liquid level of the phase-change fluid, and the phase change of the liquid does not occur.
The first data is the liquid level data of the fully heated state, including the liquid level of dry, and the second data is the liquid level data of the non-heating state or the heating state. The judgment of the liquid level is also used for determining whether the current heat source is in a heating state or a non-heating state, so that the operation state of the heat source is determined according to different conditions.
Preferably, the period of time also measured is 1 to 10 minutes, preferably 3 to 6 minutes, more preferably 4 minutes.
Preferably, the threshold is 1-10mm, preferably 4mm.
Preferably, the water level value may be an average water level value over a period of time. The water level at a certain point in the time period may be set. For example, the water levels at the end of the time period are all preferred.
4. Autonomous speed-based adjustment of vibration
Preferably, a speed sensing element is arranged in the free end of the tube bundle and used for detecting the flow velocity of fluid in the free end of the tube bundle, the speed sensing element is in data connection with a controller, the controller extracts speed data according to time sequence, the speed difference or the accumulation of the change of the speed difference is obtained through the comparison of the speed data of adjacent time periods, and when the speed difference or the accumulation of the change of the speed difference is lower than a threshold value, the controller controls a heat source to stop heating or continue heating.
The difference in speed between the front and rear time and the cumulative difference in speed detected by the speed sensor can be used to determine that the evaporation of the fluid in the interior is substantially saturated and that the volume of the fluid in the interior is not greatly changed. So that the fluid undergoes a volume reduction to thereby effect vibration. When the speed difference is reduced to a certain degree, the internal fluid starts to enter a stable state again, and heating is needed to lead the fluid to be vaporized and expanded again, so that a starting heat source is needed to heat.
The steady state of the fluid is judged according to the speed difference or the accumulation of the speed difference change, so that the result is more accurate, and the problem of error increase caused by aging due to the problem of running time is avoided.
Preferably, if the speed of the preceding period is V1 and the speed of the adjacent following period is V2, if V1 < V2 is lower than the threshold, the controller controls the heat source to stop heating; if V1 > V2, when the threshold value is lower, the controller controls the heat source to heat.
And determining whether the current heat source is in a heating state or in a non-heating state through judging the speed, so that the running state of the heat source is determined according to different conditions.
Preferably, if the speed of the preceding period is V1 and the speed of the adjacent following period is V2, if v1=v2, the heating is judged according to the following condition:
if V1 is greater than the speed of the first data, when the speed is lower than the threshold value, the controller controls the heat source to stop heating; wherein the first data is greater than a velocity of the phase-change fluid after the phase change has occurred; preferably the first data is the speed at which the phase change fluid is sufficiently phase-changed;
if V1 is less than or equal to the speed of the second data, and is lower than the threshold value, the controller controls the heat source to continue heating, wherein the speed of the second data is less than or equal to the speed at which the phase change fluid does not generate phase change.
The first data is the speed data of the fully heated state, and the second data is the speed data of no heating or just beginning heating. The above-mentioned judgment of the speed is also used to determine whether the current heat source is in a heating state or a non-heating state, so as to determine the operation state of the heat source according to different conditions.
Preferably, the number of the speed sensing elements is n, and the speed V in the current time period is calculated in sequence i And a previous time speed Q i-1 Difference D of (2) i ＝V i -Q i-1 And for n speed differences D i Performing arithmetic cumulative summation
When the value of Y is lower than the set threshold, the controller controls the heat source to stop heating or to continue heating.
Preferably, Y >0, and below the threshold, the controller controls the heat source to stop heating; if Y <0, the controller controls the heat source to heat when the value is lower than the threshold value.
And determining whether the current heat source is in a heating state or in a non-heating state through judging the speed, so that the running state of the heat source is determined according to different conditions.
Preferably, if y=0, the heating is judged according to the following condition:
if V is i If the arithmetic mean of the first data is greater than the speed of the first data, the controller controls the heat source to stop heating when the arithmetic mean is lower than the threshold value; wherein the first data is greater than a velocity of the phase-change fluid after the phase change has occurred; preferably the rate at which the phase change fluid is sufficiently phase-changed;
if V is i And if the arithmetic mean of the second data is less than the speed of the second data, the controller controls the heat source to continue heating when the arithmetic mean of the second data is less than or equal to the speed of the phase change fluid without phase change.
The first data is the speed data of the fully heated state, and the second data is the speed data of no heating or just beginning heating. The above-mentioned judgment of the speed is also used to determine whether the current heat source is in a heating state or a non-heating state, so as to determine the operation state of the heat source according to different conditions.
Preferably, the period of time for measuring the velocity is 1 to 10 minutes, preferably 3 to 6 minutes, and more preferably 4 minutes.
Preferably, the threshold is 1-3m/s, preferably 2m/s.
Preferably, the velocity value may be an average pressure value over a period of time. The speed at a certain point in the time period may also be made. For example, the speeds at the end of the time period are all preferred.
The heater, such as a water heater, shown in fig. 5, has a circular cross-section housing with the plurality of loop heat pipes disposed within the circular housing. Preferably, three loop heat pipes are arranged in the shell, and extension lines of central connecting lines of the left header, the right header and the middle evaporating pipe of the loop heat pipes form an inscribed regular triangle with a circular section. Through such setting, can make the interior fluid of heater fully reach vibrations and heat transfer purpose, improve the heat transfer effect.
Through numerical simulation and experiments, the size of the loop heat pipe and the diameter of the circular section have great influence on the heat exchange effect, the loop heat pipe is too large in size to cause the adjacent interval to be too small, the space formed in the middle is too large, the middle heating effect is not good, the heating is not uniform, and the loop heat pipe is too small in size to cause the adjacent interval to be too large, so that the whole heating effect is not good. Therefore, the invention obtains the optimal dimensional relationship through a large number of numerical simulation and experimental researches.
The distance between the centers of the left header and the right header is L1, the side length of the inscription regular triangle is L2, the radius of the axis of the innermost arc tube in the arc tube is R1, and the radius of the axis of the outermost arc tube is R2, so that the following requirements are satisfied:
10*(L1/L2)＝d*(10*R1/R2)-e*(10*R1/R2) 2 -f; where d, e, f are parameters,
42.69<d<42.71,3.63<e<3.64,119.9<f<120.1；
further preferably, d=42.702, e=3.634, f= 122.01;
of these, 720< L2<1130mm is preferred. Preferably 0.3< L1/L2<0.6.
Further preferably 0.32< L1/L2<0.4.
Preferably, the centers of the left header 21, the right header 22 and the middle evaporation tube 8 are on the same straight line.
Through the layout of the three loop heat pipe structure optimization, the whole heat exchange effect can reach the optimal heat exchange effect.
The heat source is preferably an electric heater.
While the invention has been described in terms of preferred embodiments, the invention is not so limited. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention, and the scope of the invention should be assessed accordingly to that of the appended claims.
Claims (3)
1. A loop heat pipe comprises a middle evaporating pipe, a left collecting pipe, a right collecting pipe and a plurality of pipe groups, wherein each pipe group comprises a plurality of arc-shaped pipes, the ends of adjacent arc-shaped pipes are communicated, the arc-shaped pipes form a serial structure, and the ends of the arc-shaped pipes form free ends of the arc-shaped pipes; the tube group comprises a left tube group and a right tube group, wherein the left tube group is communicated with a left header and a middle evaporation tube, the right tube group is communicated with a right header and the middle evaporation tube, so that the middle evaporation tube, the left header, the right header and the tube group form a heating fluid closed cycle, and a heat source is arranged in the middle evaporation tube; the middle evaporating pipe comprises a first pipe orifice and a second pipe orifice, the first pipe orifice is connected with the inlet of the left pipe group, the second pipe orifice is connected with the inlet of the right pipe group, the outlet of the left pipe group is connected with the left header pipe, and the outlet of the right pipe group is connected with the right header pipe; the first pipe orifice and the second pipe orifice are arranged on two opposite sides of the middle evaporation pipe; the position of the right tube group is the position of the left tube group after the left tube group rotates 180 degrees along the axis of the middle evaporation tube; the temperature sensing element is arranged in the loop heat pipe and is used for detecting the temperature in the loop heat pipe, and the temperature sensing element is in data connection with the controller.
2. The loop heat pipe of claim 1 wherein the controller controls the heat source to stop heating if the temperature in the preceding time period is T1 and the temperature in the adjacent subsequent time period is T2, if T1< T2, is below the threshold; if T1> T2, below the threshold, the controller controls the heat source to heat.
3. The loop heat pipe of claim 1 wherein the temperature sensing element is disposed at an upper end within the central evaporator tube, the left header and the right header.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910692882.5A CN112304134B (en) | 2019-07-30 | 2019-07-30 | Rotational symmetry accumulated temperature difference vibration loop heat pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910692882.5A CN112304134B (en) | 2019-07-30 | 2019-07-30 | Rotational symmetry accumulated temperature difference vibration loop heat pipe |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112304134A CN112304134A (en) | 2021-02-02 |
| CN112304134B true CN112304134B (en) | 2023-05-05 |
Family
ID=74330213
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910692882.5A Active CN112304134B (en) | 2019-07-30 | 2019-07-30 | Rotational symmetry accumulated temperature difference vibration loop heat pipe |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112304134B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1104759A (en) * | 1994-04-28 | 1995-07-05 | 山东工业大学 | Steam-water heat exchanging system with elastic tube bank |
| WO2002103263A1 (en) * | 2001-06-18 | 2002-12-27 | Showa Dendo K.K. | Evaporator, manufacturing method of the same, header for evaporator and refrigeration system |
| JP2003075024A (en) * | 2001-06-18 | 2003-03-12 | Showa Denko Kk | Evaporator, its manufacturing method, header member for the vaporizer and refrigerating system |
| CN204787972U (en) * | 2015-07-14 | 2015-11-18 | 杭州兴源节能环保科技有限公司 | Gaseous waste heat recovery device of centrifugation scale removal |
| CN107631652A (en) * | 2016-07-18 | 2018-01-26 | 赵炜 | A kind of more heat exchanger tube heat pipes of caliber change |
| CN107631653A (en) * | 2016-07-18 | 2018-01-26 | 赵炜 | A kind of more heat exchanger tube heat pipes of spacing change |
-
2019
- 2019-07-30 CN CN201910692882.5A patent/CN112304134B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1104759A (en) * | 1994-04-28 | 1995-07-05 | 山东工业大学 | Steam-water heat exchanging system with elastic tube bank |
| WO2002103263A1 (en) * | 2001-06-18 | 2002-12-27 | Showa Dendo K.K. | Evaporator, manufacturing method of the same, header for evaporator and refrigeration system |
| JP2003075024A (en) * | 2001-06-18 | 2003-03-12 | Showa Denko Kk | Evaporator, its manufacturing method, header member for the vaporizer and refrigerating system |
| CN204787972U (en) * | 2015-07-14 | 2015-11-18 | 杭州兴源节能环保科技有限公司 | Gaseous waste heat recovery device of centrifugation scale removal |
| CN107631652A (en) * | 2016-07-18 | 2018-01-26 | 赵炜 | A kind of more heat exchanger tube heat pipes of caliber change |
| CN107631653A (en) * | 2016-07-18 | 2018-01-26 | 赵炜 | A kind of more heat exchanger tube heat pipes of spacing change |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112304134A (en) | 2021-02-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111412773A (en) | Method for controlling three-valve heat exchanger through temperature difference | |
| CN112304134B (en) | Rotational symmetry accumulated temperature difference vibration loop heat pipe | |
| CN112304133B (en) | Mirror symmetry's water head control vibration loop heat pipe | |
| CN112146494B (en) | Rotational symmetry's control by temperature change vibration loop heat pipe | |
| CN112665448B (en) | Flow velocity vibration control method for heat exchanger | |
| CN112665425B (en) | Shell-and-tube heat exchanger with multi-tube box water level difference control | |
| CN112665447B (en) | Temperature descaling control method | |
| CN112665426B (en) | Shell-and-tube heat exchanger of many casees pressure difference control | |
| CN113137875B (en) | Loop heat pipe heat exchanger for heating according to pressure difference | |
| CN112964098B (en) | Loop heat pipe heat exchanger capable of switching heat sources according to speed difference | |
| CN113137876B (en) | Loop heat pipe heat exchanger for switching heat source to heat gas | |
| CN112964100B (en) | Loop heat pipe heat exchanger capable of switching heat sources according to temperature difference | |
| CN113720179B (en) | Hotel flow control shell-and-tube heat exchanger | |
| CN112880438B (en) | Heat exchanger that pressure differential was adjusted is handled to communication cloud | |
| CN112146493B (en) | Mirror symmetry's water accuse vibration loop heat pipe | |
| CN113340133B (en) | Remote pressure difference heat pipe exchanger | |
| CN113203308B (en) | Remote speed difference three-heat-source shell-and-tube heat exchanger | |
| CN114413666B (en) | Heat pipe system with flue gas monitoring and cooperative adjustment functions | |
| CN112556466B (en) | Temperature difference loop heat pipe system | |
| CN112556467B (en) | Speed difference loop heat pipe system | |
| CN113686178A (en) | Constant-control shell-and-tube heat exchanger | |
| CN111412774A (en) | Heat exchanger with four fluid liquid level difference adjustment functions | |
| CN113624036A (en) | Heat exchanger that liquid level difference was adjusted is handled to cloud | |
| CN111412772A (en) | Heat exchanger with four fluid pressure difference regulation | |
| CN113551542A (en) | Jet shell-and-tube heat exchanger |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20230307 Address after: 264209 No. 180, Wenhua West Road, Shandong, Weihai Applicant after: SHANDONG University Applicant after: WEIHAI WANFENG MAGNESIUM INDUSTRY DEVELOPMENT Co.,Ltd. Address before: 264209 No. 180, Wenhua West Road, Shandong, Weihai Applicant before: SHANDONG University |
|
| TA01 | Transfer of patent application right | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |