GB2160637A

GB2160637A - Support arrangement for tubular solar heat collector elements

Info

Publication number: GB2160637A
Application number: GB08415650A
Authority: GB
Inventors: Daniel Clelland Anderson; David Dawson
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-06-19
Filing date: 1984-06-19
Publication date: 1985-12-24
Also published as: GB8415650D0

Abstract

A solar collector comprises a parallel array of tubular collector elements supported at each end by a two part structure (4)5. The support structures ensure independent support of the outer transparent tubes 1 of the collector elements and the two fluid manifolds 10 which distribute the fluid to be heated through absorber elements 2 located inside the transparent tubes 1. Difficulties due to thermal expansion are eliminated and any individual outer transparent tube 1 which is damaged or in the case of glass broken can be readily replaced since the end support structure is easily dissembled. <IMAGE>

Description

SPECIFICATION Tubular solar collector This invention relates to the assembly of an array of tubular solar collector elements.

A tubular collector element typically consists of a long tube of glass or other suitable transparent material which has an internal axial absorber which may be a finned tube located normally but not necessarily along the central axis of the outer transparent tube.

Fluid passing along a parallel array of tubular collector elements enters and leaves by means of a manifold at either end of the tubular collector array. The fluid manifolds and the glass tubes are located and retained in some form of end structure or fixing which should cope satisfactorily with problems of thermal expansion and at the same time impart sufficient rigidity to the collector assembly to allow for safe handling of the collector assembly. It is also an advantage to be able to replace a damaged individual tube should this be necessary. A satisfactory design of solar collector must also be durable.

The invention is based on separating the location of the outer glass tubes from that of the manifolds and the interconnecting finned tube absorbers located axially inside the glass tubes. The glass tubes are retained in position by means of a suitable housing which is internally grooved to retain a soft foam sealing strip which is compressed against the outer surface of the glass tube on assembly. Subject to the friction between the foam or other suitable flexible sealing strip the glass tube is free to move both axially and radially and thereby cope with movements due to thermal expansion. The manifolds and finned tube absorbers are independently located in the correct relationship to the glass tubes. The invention incorporates a suitable design of support structure which will satisfactorily achieve these objectives.

A specific embodiment of the invention will now be described by way of an example with reference to the accompanying drawings in which: Figure 1 shows a typical tubular collector array consisting of glass tubes 1 and finned copper tube absorbers 2 located centrally along the axes of the glass tubes. The tubular collectors are located in a special locating structure 3 at either end which forms the basis of the invention.

Figure 2 illustrates the essential features of the locating structure for the tubes and manifold. The structure consists of a lower component 4 which provides a base for the completed collector assembly. This mates or slots into an upper structure 5. The preferred material for these structures is glass reinforced plastic (G.R.P.). When assembled the structure provides a circular housing 6 which has a diameter slightly in excess of that of the glass tubes. A groove 7 is provided for the purpose of retaining a suitable foam or other compressible sealing strip. Such a sealing strip may be a self-adhesive strip of neoprene foam so that the foam strip is located and stuck in the groove prior to assembly. The thickness of the foam strip is such that it exceeds the depth of the groove and thus provides a compressible contact with the glass tubes.Accurate assembly of 4 and 5 is ensured by means of a slotting arrangement 8. The assembly is held together by means of bolts or rivets through holes 9 drilled in the flanges of the upper and lower structures. The accurate assembly of component 4 to component 5 is ensured by means of the location 8.

The centre of the hexagonal hole formed by the assembly of 4 and 5 coincides with the longitudinal axis of the manifold supplying the circulating fluid to the individual solar energy collecting tubes.

Figure 3 indicates how the manifold 10 is positively located in the hexagonal hole by virtue of terminating in a preferably brass end connection 11 of corresponding hexagonal shape and incorporating also a suitable internal threaded hole 1 2 for external connection of the circuit carrying the fluid to be solar heated. This requires a hole 1 3 in the end wall of the structure. This is also illustrated in Fig. 2. The glass tubes 1 and finned tube absorbers 2 are shown in Fig. 3 when assembled with the upper structure 5 and the manifold 10 respectively.

Figure 4(a) shows a cross-section of the upper structure 5 through the vertical centreline of the circular housing 6. Fixing of the completely assembled tubular solar collector, to a roof for example, is achieved by utilising the holes 1 4.

Figure 4(b) shows the glass tube 1, finned tube absorber 2 and manifold 10 with the hexagonal end 11 assembled.

Figure 4(c) is a cross-section of the lower structure 4 through the vertical centre-line of the circular housing 6.

Figure 4(d) represents the assembly of Figs.

4(a), 4(b) and 4(c) respectively. In addition it shows the sealing strip 1 5 which supports the glass glass tubes.

The manifold 10 is located at each end in a rigid hexagonal clamp formed on the assembly of 4 and 5.

1. An end support structure for a parallel array of tubular solar energy collector tubes which separately locates and supports the glass tubes and the manifolds which distribute the fluid to be solar heated through the absorber located axially inside the glass tubes.

2. An end support structure according to Claim 1 in which thermal expansion of the glass tubes can safely occur both radially and

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Tubular solar collector This invention relates to the assembly of an array of tubular solar collector elements. A tubular collector element typically consists of a long tube of glass or other suitable transparent material which has an internal axial absorber which may be a finned tube located normally but not necessarily along the central axis of the outer transparent tube. Fluid passing along a parallel array of tubular collector elements enters and leaves by means of a manifold at either end of the tubular collector array. The fluid manifolds and the glass tubes are located and retained in some form of end structure or fixing which should cope satisfactorily with problems of thermal expansion and at the same time impart sufficient rigidity to the collector assembly to allow for safe handling of the collector assembly. It is also an advantage to be able to replace a damaged individual tube should this be necessary. A satisfactory design of solar collector must also be durable. The invention is based on separating the location of the outer glass tubes from that of the manifolds and the interconnecting finned tube absorbers located axially inside the glass tubes. The glass tubes are retained in position by means of a suitable housing which is internally grooved to retain a soft foam sealing strip which is compressed against the outer surface of the glass tube on assembly. Subject to the friction between the foam or other suitable flexible sealing strip the glass tube is free to move both axially and radially and thereby cope with movements due to thermal expansion. The manifolds and finned tube absorbers are independently located in the correct relationship to the glass tubes. The invention incorporates a suitable design of support structure which will satisfactorily achieve these objectives. A specific embodiment of the invention will now be described by way of an example with reference to the accompanying drawings in which: Figure 1 shows a typical tubular collector array consisting of glass tubes 1 and finned copper tube absorbers 2 located centrally along the axes of the glass tubes. The tubular collectors are located in a special locating structure 3 at either end which forms the basis of the invention. Figure 2 illustrates the essential features of the locating structure for the tubes and manifold. The structure consists of a lower component 4 which provides a base for the completed collector assembly. This mates or slots into an upper structure 5. The preferred material for these structures is glass reinforced plastic (G.R.P.). When assembled the structure provides a circular housing 6 which has a diameter slightly in excess of that of the glass tubes. A groove 7 is provided for the purpose of retaining a suitable foam or other compressible sealing strip. Such a sealing strip may be a self-adhesive strip of neoprene foam so that the foam strip is located and stuck in the groove prior to assembly. The thickness of the foam strip is such that it exceeds the depth of the groove and thus provides a compressible contact with the glass tubes.Accurate assembly of 4 and 5 is ensured by means of a slotting arrangement 8. The assembly is held together by means of bolts or rivets through holes 9 drilled in the flanges of the upper and lower structures. The accurate assembly of component 4 to component 5 is ensured by means of the location 8. The centre of the hexagonal hole formed by the assembly of 4 and 5 coincides with the longitudinal axis of the manifold supplying the circulating fluid to the individual solar energy collecting tubes. Figure 3 indicates how the manifold 10 is positively located in the hexagonal hole by virtue of terminating in a preferably brass end connection 11 of corresponding hexagonal shape and incorporating also a suitable internal threaded hole 1 2 for external connection of the circuit carrying the fluid to be solar heated. This requires a hole 1 3 in the end wall of the structure. This is also illustrated in Fig. 2. The glass tubes 1 and finned tube absorbers 2 are shown in Fig. 3 when assembled with the upper structure 5 and the manifold 10 respectively. Figure 4(a) shows a cross-section of the upper structure 5 through the vertical centreline of the circular housing 6. Fixing of the completely assembled tubular solar collector, to a roof for example, is achieved by utilising the holes 1 4. Figure 4(b) shows the glass tube 1, finned tube absorber 2 and manifold 10 with the hexagonal end 11 assembled. Figure 4(c) is a cross-section of the lower structure 4 through the vertical centre-line of the circular housing 6. Figure 4(d) represents the assembly of Figs. 4(a), 4(b) and 4(c) respectively. In addition it shows the sealing strip 1 5 which supports the glass glass tubes. The manifold 10 is located at each end in a rigid hexagonal clamp formed on the assembly of 4 and 5. CLAIMS

2. An end support structure according to Claim 1 in which thermal expansion of the glass tubes can safely occur both radially and axially.

3. An end support structure according to Claim 1 or 2 in which the structural strength of the glass tubes is utilised in providing a satisfactorily rigid structure with a degree of torsional flexibility which is advantageous for the installation of the collector on uneven surfaces.

4. An end support structure according to Claim 1, 2 or 3 in which the fluid manifolds are securely and accurately located in the correct position relative to the glass tubes which are themselves independently supported by the structure.

5. An end support structure according to Claim 1, 2, 3 and 4 which allows for easy dissembly and replacement of a broken glass tube.

6. An end support structure for a tubular solar collector as described with reference to the accompanying drawings.