CN100347382C - Thermal conductivity coefficient variable device and its application - Google Patents
Thermal conductivity coefficient variable device and its application Download PDFInfo
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- CN100347382C CN100347382C CNB031080898A CN03108089A CN100347382C CN 100347382 C CN100347382 C CN 100347382C CN B031080898 A CNB031080898 A CN B031080898A CN 03108089 A CN03108089 A CN 03108089A CN 100347382 C CN100347382 C CN 100347382C
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- conductivity coefficient
- variator
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- thermal conductivity
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Abstract
The present invention relates to a thermal conductivity coefficient variable device and the application thereof. The thermal conductivity coefficient variable device utilizes the temperature change at all seasons of the nature under the different conditions of positive and negative temperature. The device comprises an outer shell, wherein a water absorption material with a structure of an air layer and a water absorption material interlayer is arranged in the sealed outer shell, and certain water bodies are filled into the outer shell. The thermal conductivity coefficient variable device can be applied to foundations of road beds of railways, highways and other projects as well as buildings of which other objects need thermal insulation. The thermal conductivity coefficient variable device realizes thermal flow control between the environment and the protected objects through the characteristics of low thermal conductivity coefficient at positive temperature and high thermal conductivity coefficient at negative temperature for a system, and finally, the function for cooling the protected objects is realized. The thermal conductivity coefficient variable device has the advantages of practicality, efficiency and no influence on the environment.
Description
Technical field
The present invention relates to a kind ofly in the Permafrost Area engineering construction, effectively protect the bottom ever-frozen ground, guarantee the heat sink of engineering construction stability of foundation, refer to a kind of variator of heat conductivity coefficient especially.
Background technology
Development along with national product and regional economy, deepening continuously of the enforcement of national strategy to develop western regions and process, China now constantly carries out the construction of Important Project facilities such as railway, highway, petroleum pipeline, optical cable, water conservancy in the Permafrost Area that occupies area 22%.
Frozen soil is meant temperature below 0 ℃ or 0 ℃, and contains the various ground and the soil of ice.Ever-frozen ground is meant that frozen soil keeps for many years incessantly, some centuries are so that thousands of years.In ever-frozen ground formation and development process, because the water translocation that the freeze thawing circulation is caused tends to form certain or ice of great thickness layer (being called ground ice) on underground certain degree of depth.
Because the people is the influence of engineering measure, changed face of land heat transfer boundary condition, particularly in the high surrounding areas of the Qinghai-Tibet sun, because artificial engineering makes and implements back engineering construction heat-absorbent surface, caloric receptivity greatly increases, make that the heat population equilibrium of ever-frozen ground of bottom, various engineering measures basis is destroyed, the overall heat income is greater than expenditure, make the temperature of ever-frozen ground constantly raise, thick-layer ground ice in the ever-frozen ground constantly melts, the continuous sinking in basis, the unstability that cause engineering construction thus have a strong impact on the stability and the normal operation of various correlation engineering.For example Russia's investigation in 1994 shows, the second Siberia railway that builds up the seventies, and circuit disease rate reaches 27.5%.The circuit disease rate of operation last 100 years article one Siberia railway investigation in 1996 is 45%.China's nineteen ninety investigation shows that Qinghai-Tibet Highway disease rate at that time reaches 31.7%, and PERMAFROST IN NORTHEAST CHINA district railway disease rate reaches 40%.Simultaneously along with global climate changes warm, the annual mean ground temperature of ever-frozen ground is also constantly changeing warm, and to external world variations in temperature become responsive more, many ever-frozen ground stability region is transformed into range of instability or utmost point range of instability gradually.Existing ever-frozen ground is often thick to reach tens meters even up to a hundred meters, if just in case the ever-frozen ground unstability can enter into a series of vicious circle, and ground ice constantly melts, the face of land constantly sinks.Therefore, whether can take and use effective, practical engineering protection measure and technology, the ever-frozen ground of protection engineering foundation bottom is subjected to or avoids the influence of top engineering construction less, just becomes Qinghai-Tibet Railway and various frozen soil engineering and builds the success or failure place.At present more with regard to the Study of Interaction of engineering and frozen soil, but how efficiently and effectively to solve the successful measure of its INTERACTION PROBLEMS few.Chinese Academy of Sciences's " light in western part---protection frozen soil temperature control key technology research in the frozen soil engineering "; the major project of Chinese Academy of Sciences's knowledge innovation project " qinghai-tibet railway engineering and ever-frozen ground interact and environmental effect " (No.KZCX1-SW-04); Chinese Academy of Sciences cold area arid region environment and Engineering research institute's innovation item (CACX2002406); state natural sciences fund major project (90102006), " 973 " state key basic research development and planning project problems such as (2002CB412704) has been carried out case study at the actual engineering problem of above-mentioned key exactly.
At present; be used to protect the engineering measure of linear engineering bottom ever-frozen ground such as railway, highway to mainly contain: to improve depth of fill; lay rock revetment, sunbreaker on the embankment surface; in embankment, install air chimney additional; in embankment, lay heat insulating material, pierre-perdue, bury the heat stake underground and wait measure to reach the purpose of protection roadbed bottom ever-frozen ground.But because the restriction said method of China's Permafrost Area unique conditions all comes with some shortcomings or shortcoming.In China's Permafrost Area, especially Qinghai-Tibet, the annual mean ground temperature of a lot of ever-frozen ground is near zero degree (being called the high temperature ever-frozen ground), cause these engineering measure otherwise effect is not high, cost is too high, only on point, lower the temperature, and the requirement that is difficult to satisfy on the line of the actual requirement of engineering, lowers the temperature on the face is difficult to use in a large number in linear engineering.Therefore, in engineering practice, need higher, the feasible engineering measure in practice of novelty, effect in a hurry.
Constantly change warm today at global climate, carry out the research of stablizing the engineering measure of ever-frozen ground thermal field, stable or slow down ever-frozen ground degeneration will guarantee that engineering works stability and normal operation are significant to the carrying out smoothly of such regional engineering construction.The relevant research that is applied to coefficient of thermal conductivity changeable material in the cold district engineering or device; it is one of important directions of studying in association area of present world concerned countries; if can actively be protected scientific achievement and independent intellectual property right content that China carries out correlative study, will be had positive significance from now on correlative study and the correct application in engineering practice.
Summary of the invention
The purpose of this invention is to provide a kind of device; this kind device need not any power; utilize nature variation of temperature throughout the year; this device is by the higher relatively characteristics of coefficient of thermal conductivity under whole, winter relatively low at coefficient of thermal conductivity under the summer positive temperature subzero temperature; it is variator of heat conductivity coefficient; realize the hot-fluid control between environment and the protected object, the final cooling effect that realizes protected object.This device is because the existence of internal water has the very high characteristics of heat capacity simultaneously, utilizes the time of ever-frozen ground district cold season greater than the feature of warm season time, also has the function that stores the cold energy in winter, reaches the further cooling to the protected object in bottom.Because this device makes full use of the variation and the cold energy of natural temperature,,, because it is embedded in below the face of land, environmental protection had positive role equally simultaneously not to any hazardous substances of airborne release without any need for power.
The present invention also aims to use not only and can play good stabilization to the thermal field of ever-frozen ground bottom railway, highway embankment or the building in ever-frozen ground district by it, can reduce simultaneously the minimum altitude of embankment requirement, significantly reduce construction costs, shorten the construction period.
The present invention also aims to by its application at Han Qu, can be to being arranged at the underground cooling soil moisture conservation effect that is used to preserve the natural cold cellar for storing things of fruit or vegetables.
Purpose of the present invention can realize by following measure:
A kind of variator of heat conductivity coefficient comprises shell, and described shell is a can; Be provided with absorbent material, air layer and water body in the enclosure, wherein absorbent material is separated air layer and water body.
Described absorbent material is separated into multilayer with air layer.
Described absorbent material is separated into multilayer with water body.
Described absorbent material is selected from least a in the super absorbent polymer system, flower mud, bonded fabric of water-absorbing sponge, polyacrylic acid and polyacrylamide combination.
Described shell is selected from metal, nonmetallic a kind of.Its role is to stop distributing of internal moisture, protect the complete of internal construction.
A kind of application of variator of heat conductivity coefficient; wherein variator of heat conductivity coefficient is used for ever-frozen ground district railway; highway embankment; and other linear engineerings or building bottom; or the underground face of land that is used to preserve the natural cold cellar for storing things of fruit or vegetables; at railway; highway embankment and other linear engineerings or building bottom; or at railway; the surperficial both sides of highway embankment; or on the underground face of land that is used to preserve the natural cold cellar for storing things of fruit or vegetables, the variator of heat conductivity coefficient of laying the 10-30 cm thick can be implemented in that environment temperature is controlled for the hot-fluid of positive temperature heat insulation relatively and relative heat conduction under subzero temperature down and to the cooling effect of protected object.
A kind of application of variator of heat conductivity coefficient lays around building or structure wherein that variator of heat conductivity coefficient can realize that itself and the hot-fluid of environment are controlled and to the cooling effect of building or structure.
A kind of application of variator of heat conductivity coefficient wherein is used for variator of heat conductivity coefficient the object that needs hot-fluid control and lower the temperature.
Operating principle of the present invention is the absorbent material that adds in airtight container in layer, every layer of alternate certain distance, and forming structure is the structure of air layer and absorbent material alternating layers, and adds some water bodys.Water body comes together in the water storage position of bottom of device under action of gravity.Because the coefficient of thermal conductivity of air is very low to be 0.024W/mK; under the condition of positive temperature; the air layer of this kind structure middle and upper part can play good thermal resistance effect, causes the coefficient of thermal conductivity of whole device relatively low, and what stop outside heat enters the protected frozen soil in bottom.When entering cold season, be embedded in this kind device in road bed or the roadbed under the unidirectional condition of freezing, at first the absorbent material of the superiors begins cooling.Because the good water absorption character of absorbent material is when cold wall surface cools, when temperature drops to air dew point, adsorbing as thin as a wafer a water layer on the cold wall surface.When temperature further drops to the three phase point of water or when lower, water layer is solidified as ice sheet.When cold wall surface temperature drops to below 0 ℃ and stablizes, airborne steam is sublimated on this ice sheet and is formed the crystallization embryo of ice, and begin steam thus and on the crystallization embryo, constantly sublimate, form the crystal of the frost of needle-like or column, constantly development thus, the frost layer is full of whole first floor air layer behind experience crystalline growth phase, white layer growth phase and frost layer acme.Owing to the minimizing of water in air steam, the moisture in the absorbent material of bottom can constantly discharge in air, reaches a kind of aqueous vapor balance in this process.Because the minimizing of bottom absorbent material internal moisture, absorbent material can partly be aspirated moisture from the bottom water storage again and be replenished scattering and disappearing of internal moisture.Be full of the frost layer in the first floor air layer after, utilizing the coefficient of thermal conductivity of ice is the characteristics of 2.21～2.236W/mK, makes second layer absorbent material by becoming the circulation that cold wall surface begins said process again very soon.Constantly circulation thus, the water body that the bottom water storage is partly stored all are converted into the frost layer that forms in air layer.Because the coefficient of thermal conductivity of ice is higher relatively, the whole coefficient of thermal conductivity of device also can increase thereupon in this case, helps outside the shedding that outside cold enters bottom frozen soil and bottom heat.According to above-mentioned in evolution; under the condition that positive at all seasons subzero temperature changes; the coefficient of thermal conductivity of this kind device can have a bigger difference under positive gentle subzero temperature two states; thereby realize carrying out hot-fluid control between environment and the protected object, finally reach effect the stable and protection of ever-frozen ground.This device is because the existence of inner water body simultaneously because the heat capacity of water is very high and the time of ever-frozen ground district cold season greater than the warm season time, this kind device also has the function that stores the cold energy in winter, further reaches the purpose to the protection of bottom ever-frozen ground.The effect of closed container is to stop scattering and disappearing of internal moisture, can effectively protect the inner laminated structure to avoid destroying under external load action because closed container has certain intensity simultaneously.
Because frosting mostly occurs and solidifies in the processes such as purification, cryogenic liquid storage at air-conditioning refrigeration system, cargo refrigeration system, gas, and taking off or aloft airframe surface, on the glass window minute surface of locomotive, ship-handling chamber, be considered to have much more harms than benefits, about Frosting Research and relevant patent also are to carry out around how eliminating this influence.This patent is from a brand-new angle, how utilizes, improves and promote the growth of frost layer in the confined space, changes above-mentioned air layer coefficient of thermal conductivity and changes and carry out the frosting process study, and declare patent in conjunction with result of study.
The present invention has following advantage compared to existing technology:
This patent closely carries out specific requirement such as cost, effect, operability in the engineering practice, and this kind device can be shaped in indoor or factory process, at the scene directly cloth if install.By costing and comparison, its cost is a little less than the cost of engineering measures such as heat insulating material, jackstone roadbed, elevated formation level, ventilated embankment.The more important thing is by laboratory test and calculate relatively, be better than other engineering measure aspect the effect of protection ever-frozen ground in kind of engineering measure.Therefore have simple, cost performance is high, in engineering practice strong strong operability, stablize plurality of advantages such as ever-frozen ground ground temperature field effect is obvious.
Embankment is mainly absorbed heat by three external surfaces after construction is finished, and wherein again because embankment both side surface area will be main heat-absorbent surface much larger than top surface, it is about 1.5 times of Schattenseite that tailo receives solar radiation with it, is topmost heat-absorbent surface.The heat that is absorbed conducts heat to the ever-frozen ground that underlies by the roadbed bottom surface.Therefore, on the shallow surface of tailo or the shallow surface of both sides side slope or lay this kind device near the roadbed bottom surface, just can control hot-fluid, stablizing ever-frozen ground thermal field, bottom, stablizing the frozen soil basis and play a multiplier role at key position.Therefore, has the advantage that to carry out the effect of hot-fluid control and cooling at key position.
The finished product of the present invention after by factory process can be made 1～2m by actual demands of engineering
2The unit, can be by the construction of the job practices of heat insulating material, the axial level on road along the line is laid, and carries out the overall thermal current control and the stable ever-frozen ground thermal field of frozen soil engineering.Therefore have the engineering construction mass-type foundation, the advantage that the effect of its stability was controlled and promoted to hot-fluid is carried out in especially linear engineering mass-type foundation.
Description of drawings
Figure 1A is installed in the assembling schematic diagram of roadbed bottom for variator of heat conductivity coefficient of the present invention
Figure 1B is installed in the assembling schematic diagram of roadbed side for variator of heat conductivity coefficient of the present invention
Fig. 2 is the internal construction schematic diagram of variator of heat conductivity coefficient of the present invention
Fig. 3 A is a principle laboratory test results photo under the positive temperature condition of the present invention
Fig. 3 B is a principle laboratory test results photo under the subzero temperature condition of the present invention
Fig. 4 is principle laboratory test temperature test result of the present invention
Number in the figure is described as follows:
1-roadbed 2-variator of heat conductivity coefficient 3-closed container
4-absorbent material 5-air layer 6-water body
Concrete embodiment
The present invention also will be described in further detail embodiment in conjunction with the accompanying drawings:
With reference to Figure 1A, B, Fig. 2, be a kind of coefficient of thermal conductivity type variable frozen soil basis, comprise being located at the variator of heat conductivity coefficient of laying in the roadbed 12; Wherein said variator of heat conductivity coefficient 2 comprises: sealing shell 3, absorbent material 4, air layer 5 and water body 6.Wherein on water body 6, establish absorbent material 4, and air layer 5 is separated into multilayer by absorbent material 4.Described closed container is by metal, a kind of making in nonmetal, as plastics or concrete; Described absorbent material is selected from least a in the super absorbent polymer system, flower mud, bonded fabric of water-absorbing sponge, polyacrylic acid and polyacrylamide combination.
This kind device has been carried out the test of coefficient of thermal conductivity in experiment indoor application comparison method.The test absorbent material is selected colored mud (green material among Fig. 3) for use, and is built on stilts with every layer with small part flower mud in the peripheral local area of flower mud, forms needed stepped construction, and injects certain water yield.This kind device lower surface remains on about 0 ℃ in test, and the upper surface is respectively 15 ℃ ,-15 ℃; And simulation reduces the growing state of inner ice crystal frost layer under 1 ℃ of unidirectional freezing condition every day in the upper surface.The coefficient of thermal conductivity of coefficient of thermal conductivity under positive temperature condition through this device of test is 0.21W/mK, and the coefficient of thermal conductivity under the subzero temperature condition is 1.2W/mK, and coefficient of thermal conductivity ratio is 5.71.Can see that by Fig. 3 growth has extraordinary ice crystal frost layer in air layer simultaneously.
Calculate by indoor 30 years simulation analysis this device, under all the same terms, under the specified conditions that overlay this material of 10cm, can make at annual mean ground temperature and constantly move down by original for-0.5 ℃ high temperature ever-frozen ground district road puts the portion ever-frozen ground upper bound, melt circle and constantly enlarge, the maximum amount of moving down reaches 10.5m, the continuous unstability of ever-frozen ground, the upper bound maximum amount of moving down of changing into ever-frozen ground is not more than 1m, and ever-frozen ground is in stable state substantially.
Claims (8)
1, a kind of variator of heat conductivity coefficient comprises shell (3), and described shell (3) is a can; It is characterized in that being provided with in shell (3) absorbent material (4), air layer (5) and water body (6), wherein absorbent material (4) is separated air layer (5) and water body (6).
2, variator of heat conductivity coefficient as claimed in claim 1 is characterized in that described absorbent material (4) is separated into multilayer with air layer (5).
3, variator of heat conductivity coefficient as claimed in claim 1 is characterized in that described absorbent material (4) is separated into multilayer with water body (6).
4, variator of heat conductivity coefficient as claimed in claim 1 is characterized in that described absorbent material (4) is selected from least a in the super absorbent polymer system of water-absorbing sponge, polyacrylic acid and polyacrylamide combination, flower mud, the bonded fabric.
5, variator of heat conductivity coefficient as claimed in claim 1 is characterized in that described shell is selected from metal, a kind of in nonmetal.
6; the application of the described variator of heat conductivity coefficient of a kind of claim 1; it is characterized in that variator of heat conductivity coefficient is used for railway; highway embankment and other linear engineerings or building bottom; or the underground face of land that is used to preserve the natural cold cellar for storing things of fruit or vegetables; at railway; highway embankment and other linear engineerings or building bottom; or at railway; the surperficial both sides of highway embankment; or on the underground face of land that is used to preserve the natural cold cellar for storing things of fruit or vegetables, the variator of heat conductivity coefficient of laying the 10-30 cm thick can be implemented in that environment temperature is controlled for the hot-fluid of positive temperature heat insulation relatively and relative heat conduction under subzero temperature down and to the cooling effect of protected object.
7, the application of the described variator of heat conductivity coefficient of a kind of claim 1 is characterized in that establishing that variator of heat conductivity coefficient can realize that itself and the hot-fluid of environment are controlled and to the cooling effect of building or structure around building or structure.
8, the application of the described variator of heat conductivity coefficient of a kind of claim 1 is characterized in that the object that variator of heat conductivity coefficient is used for the control of need hot-fluid and lowers the temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031080898A CN100347382C (en) | 2003-04-30 | 2003-04-30 | Thermal conductivity coefficient variable device and its application |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031080898A CN100347382C (en) | 2003-04-30 | 2003-04-30 | Thermal conductivity coefficient variable device and its application |
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| CN1478962A CN1478962A (en) | 2004-03-03 |
| CN100347382C true CN100347382C (en) | 2007-11-07 |
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| CNB031080898A Expired - Fee Related CN100347382C (en) | 2003-04-30 | 2003-04-30 | Thermal conductivity coefficient variable device and its application |
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100385078C (en) * | 2005-07-09 | 2008-04-30 | 中国科学院寒区旱区环境与工程研究所 | Use of concrete hollow block for regulating ever-frozen roadbed temperature |
| CN100374660C (en) * | 2005-09-09 | 2008-03-12 | 中国科学院寒区旱区环境与工程研究所 | Hollow composite layer to low temperature field of frozen soil roadbed |
| CN100374661C (en) * | 2005-09-28 | 2008-03-12 | 中国科学院寒区旱区环境与工程研究所 | Natural cold-energy variator of heat conductivity coefficient |
| CN102084064B (en) * | 2009-12-31 | 2012-09-05 | 中交第一公路勘察设计研究院有限公司 | Method for protecting roadbeds in frozen soil area and pavement structure |
| CN110715568A (en) * | 2019-09-26 | 2020-01-21 | 广西大学 | One-way cold guide pipe utilizing phase change conduction |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2378618Y (en) * | 1998-06-01 | 2000-05-17 | 潘梓屏 | Heat-insulating plate |
| JP2001295387A (en) * | 2000-04-14 | 2001-10-26 | Takenaka Komuten Co Ltd | Outside heat insulation structural body |
| CN2704621Y (en) * | 2003-04-30 | 2005-06-15 | 中国科学院寒区旱区环境与工程研究所 | Heating conductive coefficient variable apparatus |
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2003
- 2003-04-30 CN CNB031080898A patent/CN100347382C/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2378618Y (en) * | 1998-06-01 | 2000-05-17 | 潘梓屏 | Heat-insulating plate |
| JP2001295387A (en) * | 2000-04-14 | 2001-10-26 | Takenaka Komuten Co Ltd | Outside heat insulation structural body |
| CN2704621Y (en) * | 2003-04-30 | 2005-06-15 | 中国科学院寒区旱区环境与工程研究所 | Heating conductive coefficient variable apparatus |
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| CN1478962A (en) | 2004-03-03 |
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