DE9400958U1 - Solar collector with flexible connection of condenser and evaporator unit - Google Patents

Description

Solar collector with flexible connection of capacitor

and evaporator unit

The subject of the invention is a solar collector with a heat pipe, wherein the connection between the condenser and the evaporator unit is flexible.

Solar collectors are suitable for converting solar radiation into heat and for transporting the heat further with the greatest possible efficiency using a heat transport fluid, which can be water or air, for example.

Solar collectors of the type described here comprise a heat pipe, the essential function of which is the transfer and distribution of heat by evaporation and condensation of a working fluid (heat transfer medium). The essential feature of a heat pipe is that the energy required to allow the fluid and vapor to flow completely through the heat source provided in the presence of gravity, so that no external pumps are required. The use of such heat pipes in solar collectors is known, for example, from GB-2 023 803 A and GB-2 023 804 A.

Telephone: (02 21) 131&Ogr;41 Telex: 888 2307 dopa d Telefax: (0221) 134297 (02 21)134881 Telegram; Oompatent np

. fctonter Accounts

*.^al, Oprenheimjr. iCie., Cologne (BL2 37O3O2OO) Account no. 10760 J CJeutsc-e Bank AG Cologne (BLZ 37&Ogr;7&Ogr;&Ogr;6&Ogr;) Account no. 1165018 * Postgirr Cologne (BLJZ 37010O5O) Account no. 654-50O

Solar collectors also include a heat exchange system in which the condenser is one of the essential parts. The condenser is usually located in a collecting line through which a heat transport fluid is passed, which removes the heat from the condenser and transfers it. Accordingly, it is necessary to provide sufficient heat transfer from the condenser to the heat-transporting fluid in the collecting line. In addition, it is necessary to adapt the condenser to the output power of the collector. It is also necessary to achieve the lowest possible thermal resistance between the condenser and the heat transport fluid in the collecting line.

Another requirement for satisfactory solar collectors is a simple design of the solar collector so that the individual components are as easy to assemble and replace as possible. Particular difficulties arise when assembling condensers and manifolds precisely, especially with bulky heat pipes.

The object of the present invention is to simplify the assembly of known solar collectors with heat pipes.

The above object is achieved by a solar collector with a heat pipe comprising a collecting line (F) and a condenser (A), characterized in that the connection between the condenser (A) and the evaporation unit (C) consists of a flexible metal bellows (B).

The figure shows a solar collector with an evacuated glass tube or any other transparent material (E) containing an absorber plate (D) connected to an evaporator unit (C) of the heat pipe by means of a cylindrical condenser (A). The connection of the condenser (A) to the evaporator unit is made by a flexible, in particular metallic neck, namely a

Metal bellows (B), preferably made of copper, are provided.

The flexible connection of the condenser (A) and heat pipe not only improves the range of possible applications when used on sloping roofs, but also promotes the thermal expansion behavior of the manifold (F), whereby an arrangement of the manifold (F) and thus of the condenser (A) inclined to the horizontal is also possible, which enables a complete return flow of the working fluid into the evaporator. .

Aluminium blocks (G) are formed onto the collecting line (F) made of copper or a copper alloy, for example by die casting directly onto the copper pipe. The aluminium blocks (G) in turn have semi-cylindrical recesses (K) which have exactly the same shape, in particular the semi-cylindrical shape, of the capacitor (A).

The condenser (A) is inserted into the aluminum block (G) and held, for example, by means of a clamp (H) made of a material with good thermal conductivity, the clamp being fastened to the aluminum block (G) by a series of bolts or nuts, so that the condenser (A) forms a firm connection with the aluminum block (G), which ensures efficient heat transport from the condenser (A) to the aluminum block (G), the heat transport fluid, in particular water, circulating in the collecting line (F).

The entire structure (K) of the collecting line (F) is held by a support frame (L) which is parallel to the evacuated glass tube (E) but has an angle of inclination of, for example, 10°.

The heat transfer fluid (preferably water) flows through the collection line (F) and extracts heat from the condenser (A). At the inlet or outlet of the collection line (F), the inlet or

—4—
Outlet (J) is attached.

In a preferred aspect of the present invention, the solar collector comprises a transparent cover and an absorption unit. The absorption unit has a planar configuration for absorbing solar energy radiation, the unit comprising at least one closed metallic channel (metal tube) with longitudinal extension and a working fluid (heat transfer medium) suitable for evaporation. An evaporation unit (evaporator) is in thermal contact with the absorber. A condenser device (condenser) is located spatially at a higher level than the absorber during the operation of the system, the condenser (A) being received by a manifold (F) which causes a heat transport fluid to flow.

When the solar collector is in use and no solar radiation hits the collector, the working fluid is collected in the bottom end part of the evaporation device (evaporator) of the heat pipe. When solar radiation then hits the collector, the entire plate of the absorption unit and thus also the evaporation channel is heated. The working fluid located at the bottom of the evaporation channel begins to evaporate and transfers the heat to the condenser (A), whereby energy is released through the condensation process.

The condenser (A) of the collector with heat pipe is in direct thermal contact with the heat transport fluid (e.g. water) in the collecting line (F), whereby the heat is transferred.

The transparent shell of the solar collector is preferably evacuated, whereby the absorber should have as low a heat radiation property as possible. Accordingly, the loss of radiation energy is very small, so that the temperature

•&phgr;&phgr;&phgr; · · · ··· ····
• φ φ φ φ · ·

the absorption device can reach temperatures well above about 200 ⁰ C. However, corresponding solar collectors are usually designed for a maximum application temperature of up to 100 ⁰ C.

However, if no energy is consumed, for example due to a fault within the circulation system of the manifold (F) or due to low heat consumption in the system, the temperature in the condenser (A) can easily exceed the desired maximum temperature of 100 ⁰ C. To avoid any overheating and possible destruction of the system, special safety measures must be taken if necessary to make the system safe for the user, whereby an exact amount of the working fluid in the heat pipe is of particular importance.

Claims (1)

Protection claims 1. Solar collector with heat pipe, comprising a collector conductor (F) and a condenser (A), characterized in that the connection between the condenser (A) and the evaporator unit (C) consists of a flexible metal bellows (B).