CN202813844U - Snake-shaped multiple-tube type vacuum heat-collection tube - Google Patents

Abstract

The utility model relates to the technical field of solar energy and discloses a snake-shaped multiple-tube type vacuum heat-collection tube. The multiple-tube type vacuum heat-collection tube comprises a transparent shell and a snake-shaped slim tube which is formed by the serial connection of a plurality of slim tubes which are parallel to each other, wherein a vacuum is formed between the shell and the snake-shaped slim tube. As a plurality of heat-collection tubes are used by the snake-shaped multiple-tube type vacuum heat-collection tube in a concentration and serial connection way, the snake-shaped multiple-tube type vacuum heat-collection tube has the advantages of high speed of temperature increase, small temperature difference, high heat exchange rate, wild application range and the like.

Description

Snakelike multitube vacuum heat collection pipe

Technical field

The utility model relates to technical field of solar, particularly a kind of snakelike multitube vacuum heat collection pipe.

Background technology

In the heat utilization of solar energy, key is that the radiant energy with the sun is converted to heat energy.Because solar energy relatively disperses, and must manage it is put together, so solar thermal collector is the various key components of utilizing solar energy equipment.Solar thermal collector is to absorb solar radiation to make it the device that is converted to heat energy and passes to thermal medium.Although solar thermal collector is not the end product that directly satisfies the needs of consumers, solar thermal collector is the critical component that forms various Solar Energy Heat Utilization System.Being that solar water heater, solar cooker, active solar house, solar energy greenhouse or solar energy drying, solar industry heating, solar energy thermal-power-generating etc. all be unable to do without solar thermal collector, all is as the power of system or core component with solar thermal collector.Common are plate, vacuum tube type and focus solar collector.

The vacuum tube type solar energy heat collector can be subdivided into all-glass vacuum tube type, heat-tube vacuum tubular type, U-shaped pipe vacuum tube formula.Commonly used is the all-glass vacuum tube type thermal-collecting tube, consisted of by inside and outside two glass tubes, form vacuum chamber between the inner and outer pipe, the outer surface of inner tube is provided with solar selectively absorbing coating, transmission heat transfer medium (water) in the inner tube, the thermal-collecting tube of this structure has safety, energy-saving and environmental protection, economic dispatch advantage.But its shortcoming is to bear that hydraulic pressure is low, water-holding quantity is many, and heat transfer rate is slow, and available hot water amount is few, all the time according to the time heat loss increase, can not export the hot water of higher temperature.Present vacuum tube type heat collection pipe generally is applied in the low temperature domestic solar water heater occasion about 20-80 ℃, can't be used in the occasion that needs elevated operating temperature in 150-400 ℃.

Therefore, this area is in the urgent need to researching and developing the solar energy heat collection pipe of a kind of high heat absorption efficient, low thermal emissivity, elevated operating temperature.

The utility model content

The purpose of this utility model is to provide a kind of snakelike multitube vacuum heat collection pipe, solves the existing lower limitation of thermal-collecting tube operating temperature, promotes the high temperature of thermal-collecting tube to use.

For solving the problems of the technologies described above, the utility model provides snakelike multitube vacuum heat collection pipe, comprising: transparent shell; Snakelike tubule is composed in series by many tubules parallel to each other; Be set to vacuum between housing and the snakelike tubule.

Preferably, the diameter of snakelike tubule is 3-10mm.

Preferably, the pipe thickness of snakelike tubule is 0.3mm-1mm.

Preferably, snakelike tubule is metal tube or glass tube.

Preferably, the generating surface at snakelike tubule arranges corrugated heat absorbing fins, heat absorbing fins surface coating coating for selective absorption.

Preferably, between heat absorbing fins and coating for selective absorption, lay metallic reflector.

Preferably, metallic reflector is silver foil or aluminium foil.

Preferably, snakelike tubule is two-layer.

Preferably, transparent shell is cylindrical or elliptical cylinder-shape.

Preferably, the transparent shell lateral wall applies anti-reflection film.

The utility model compared with prior art, the main distinction and effect thereof are: the sectional area that the snake pipe that many tubules are in series is compared with single bassoon is less, few with oil mass, so the preheat temperature loss is less, the short distance temperature rise is faster, have good, the advantage such as have a narrow range of temperature of heat exchange, greatly reduce pre-heat loss.The optimal design of snakelike tubule radius, conversion and the exchange efficiency of solar energy optical-thermal have greatly been improved, the waveform heat absorbing fins that is arranged on the coiled pipe top forms light trapping, make light at heat absorbing fins surface Multi reflection, improve absorptivity, the coating for selective absorption that is plated in waveform heat absorbing fins outer surface is used for absorbing the sunshine visible light, reduce infra-red radiation, further improve the absorption efficiency to sunshine, reduce radiation efficiency, thereby improve the operating temperature of thermal-collecting tube; Metal reflective coating is used for reducing radiation loss as far as possible, thereby further improves the operating temperature of thermal-collecting tube.

Description of drawings

Fig. 1 is the structural representation of the first embodiment of the snakelike multitube vacuum heat collection pipe of the utility model;

Fig. 2 is the cut-away view of the first embodiment of the snakelike multitube vacuum heat collection pipe of the utility model;

Fig. 3 is the diameter optimal datagram of the snakelike multitube vacuum heat collection pipe of the utility model;

Fig. 4 is the structural representation of the second embodiment of the snakelike multitube vacuum heat collection pipe of the utility model.

The specific embodiment

In the following description, in order to make the reader understand the application better many ins and outs have been proposed.But, persons of ordinary skill in the art may appreciate that even without these ins and outs with based on many variations and the modification of following each embodiment, also can realize each claim of the application technical scheme required for protection.

For making the purpose of this utility model, technical scheme and advantage clearer, below in conjunction with accompanying drawing embodiment of the present utility model is described in further detail.Same or analogous member uses the same reference numerals to represent among the figure.

Referring to Fig. 1, Fig. 2, show the first embodiment of snakelike multitube vacuum heat collection pipe of the present utility model, as shown in the figure, this thermal-collecting tube comprises: columniform transparent shell 1; Be set to vacuum between snakelike tubule 2,1 housings that are composed in series by many tubules parallel to each other and the snakelike tubule 2.Snakelike tubule 2 can be metal tube or glass tube.Metal tube can be applied in the occasion of higher pressure, and lower, the technology maturation of the cost of glass tube is with a wide range of applications.

The sectional area that the snake pipe that many tubules are in series is compared with single bassoon is less, and is few with oil mass, so the preheat temperature loss is less, the short distance temperature rise is faster, has good, the advantage such as have a narrow range of temperature of heat exchange, greatly reduces pre-heat loss.

The diameter of many tubules is 3-10mm, and the pipe thickness of many tubules is 0.3mm-1mm.Referring to Fig. 3, in the pipeline fluid heat transfer process, the relation between heat flow density q and the heat transfer temperature difference Δ T is as follows: q=h Δ T, h are convection transfer rate, and it is as follows with the interior velocity of medium u of pipe and pipeline inner diameter d relation:

Therefore,

Consider the heat transfer effect of a heat exchange pipeline, except the exchange capability of heat of considering fluid and tube wall, still need and consider pipeline heat radiation itself, the media flow required drive consumes, pipeline itself heat storage etc., guaranteeing to consider the total amount adduction of above-mentioned each amount in the identical coefficient of heat transfer situation.

The heat dissipation capacity of pipeline own is:

$P_{h\_\mathrm{pipi}}=n\frac{T-T_a}{\frac{\ln ((d+2{\mathrm{\δ}}_{\mathrm{insulate}})/d)}{2\mathrm{\π\λ}}+\frac{1}{\mathrm{h\π}(d+2{\mathrm{\δ}}_{\mathrm{insulate}})}}$

$=n\frac{T-T_a}{\frac{\ln (({\mathrm{<figure-callout\; id="0"\; label="d"\; filenames="HDA00002086602900031.png"\; state="\{\{state\}\}">d</figure-callout>}}_0/n+2{\mathrm{\&delta;}}_{\mathrm{insulate}})/({\mathrm{<figure-callout\; id="0"\; label="d"\; filenames="HDA00002086602900031.png"\; state="\{\{state\}\}">d</figure-callout>}}_0/n))}{2\mathrm{\&pi;\&lambda;}}+\frac{1}{\mathrm{h\&pi;}({\mathrm{<figure-callout\; id="0"\; label="d"\; filenames="HDA00002086602900031.png"\; state="\{\{state\}\}">d</figure-callout>}}_0/n+2{\mathrm{\&delta;}}_{\mathrm{insulate}})}}$

The consumption of power is:

$P_{h-\mathrm{pump}}=\frac{5\mathrm{\&rho;\&xi;\&pi;}{d}_0{u}^3}{16}$

The thermal capacitance of pipeline own:

$P_{h-\mathrm{heating},\mathrm{steel}}={\mathrm{nc}}_{p,\mathrm{steel}}{\mathrm{\&rho;}}_{\mathrm{steel}}\frac{\mathrm{\&pi;}}{4}{(({\mathrm{<figure-callout\; id="0"\; label="d"\; filenames="HDA00002086602900031.png"\; state="\{\{state\}\}">d</figure-callout>}}_0/n)+2{\mathrm{\&delta;}}_{\mathrm{wallthick}})}^2-\left({{\mathrm{<figure-callout\; id="0"\; label="d"\; filenames="HDA00002086602900031.png"\; state="\{\{state\}\}">d</figure-callout>}}_0/n)}^2\right)\mathrm{\&Delta;T}/t/3600$

$P_{h\_\mathrm{heating},\mathrm{oil}}=c_{p,\mathrm{oil}}{\mathrm{\&rho;}}_{\mathrm{oil}}\frac{\mathrm{\&pi;}}{4}\left(\frac{{\mathrm{<figure-callout\; id="0"\; label="d"\; filenames="HDA00002086602900031.png"\; state="\{\{state\}\}">d</figure-callout>}}_0^2}{n}\right)\mathrm{\&Delta;T}/t/3600$

N is pipeline quantity, and take 70mm as diameter, pipeline quantity is long-pending identical with product and 70mm pipe section that pipe section amasss.When coefficient of heat transfer h remains unchanged, above-mentioned every merging is investigated, its result as shown in Figure 3, so the minimum power consumption place is the pipeline optimum size, the therefore more excellent diameter 3-10mm that is of a size of of many tubules, wall thickness 0.3mm-1mm.The optimal design of many tubule radiuses has improved conversion and the exchange efficiency of solar energy optical-thermal greatly.In certain specific embodiment, the single tube of snakelike tubule is of a size of Φ 6*0.6mm, and tube pitch is 10mm, and interlamellar spacing is 6mm.

Generating surface at snakelike tubule arranges corrugated heat absorbing fins 3, is arranged on the waveform heat absorbing fins 3 of coiled pipe top for chamber structure, can form light trapping, makes light at heat absorbing fins 3 surperficial Multi reflections, improves absorptivity and heat transfer rate.

The heat absorbing fins surface applies coating for selective absorption.Coating for selective absorption can select the material structures such as semiconductor absorption-metallic reflection tandem surface, metal-dielectric composite, dielectric-metal interference stack surface, intrinsic selective absorption surface or little not plane surface to consist of.The materials such as Si/Ge/-Al/Au/Cu/Al/Pt/W/Ni can be selected in semiconductor absorption-metallic reflection tandem surface.The metal-dielectric composite can be selected Pt-Al ₂O ₃, Ni-SiO ₂, Ni/Co/Mo/Au/W/Pt-Al ₂O ₃, Al-AlN; Mo-MoO ₂Or the material such as W-WO2.ZrB can be selected in dielectric-metal interference stack surface ₂, Mo/Co/Cr-Cr ₂O ₃, Mo-AlN or Au-TiO ₂The materials such as/MgO.Intrinsic Gettering selective absorption surface W, HfC or Cu ₂The materials such as S.Little not plane surface is optional with materials such as Cu, Ni, SS, Re or W.In the present embodiment, coating for selective absorption is made of metallic reflector and the semiconductor absorption layer that is formed on the metallic reflector.The metallic reflection layer material is Ge, and the material of semiconductor absorption layer is Al.The coating for selective absorption that is plated in the vacuum heat-collecting tube outer surface is used for absorbing the sunshine visible light, reduces infra-red radiation, improves the absorption efficiency to sunshine, reduces radiation efficiency, thereby improves the operating temperature of thermal-collecting tube.

Between coating for selective absorption and heat absorbing fins 3, lay metallic reflector.Metallic reflector is silver foil or aluminium foil.Be used for reducing radiation loss as far as possible, improve the operating temperature of thermal-collecting tube.

Snakelike tubule 2 is two-layer.Double-deck heat absorption serpentine coil can more large-area contact heat absorbing fins, improves heat absorption efficiency.Porch at snakelike tubule is connected header 4 with the exit, as the joint of snakelike multitube thermal-collecting tube.

Transparent shell 1 lateral wall applies anti-reflection film.Anti-reflection film is used for improving the impingement rate of sunshine, thereby further improves the operating temperature of thermal-collecting tube.

Referring to Fig. 4, show the second embodiment of the present utility model, the difference of this embodiment and the first embodiment is: transparent shell 1 is shaped as ellipse, and ellipsoidal structure can be saved the volume of thermal-collecting tube, greatly reduce taking up room of thermal-collecting tube, improve the area utilization of thermal-collecting tube.

Although by reference some preferred embodiment of the present utility model, the utility model is illustrated and describes, but those of ordinary skill in the art should be understood that and can do various changes to it in the form and details, and do not depart from spirit and scope of the present utility model.

Claims (10)

1. a thermal-collecting tube is characterized in that, comprising:

Transparent shell;

Snakelike tubule is composed in series by many tubules parallel to each other;

Be set to vacuum between described housing and the snakelike tubule.

2. thermal-collecting tube according to claim 1 is characterized in that, the diameter of described snakelike tubule is 3-10mm.

3. thermal-collecting tube according to claim 2 is characterized in that, the pipe thickness of described snakelike tubule is 0.3mm-1mm.

4. thermal-collecting tube according to claim 3 is characterized in that, described snakelike tubule is metal tube or glass tube.

5. thermal-collecting tube according to claim 4 is characterized in that, at the generating surface of described snakelike tubule corrugated heat absorbing fins is set, and the heat absorbing fins surface applies coating for selective absorption.

6. thermal-collecting tube according to claim 5 is characterized in that, lays metallic reflector between heat absorbing fins and coating for selective absorption.

7. thermal-collecting tube according to claim 6 is characterized in that, described metallic reflector is silver foil or aluminium foil.

8. thermal-collecting tube according to claim 7 is characterized in that, described snakelike tubule is two-layer.

9. thermal-collecting tube according to claim 8 is characterized in that, described transparent shell is cylindrical or elliptical cylinder-shape.

10. thermal-collecting tube according to claim 9 is characterized in that, described transparent shell lateral wall applies anti-reflection film.

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