FR2610968A1 - Method and device for limiting the temperature rise in buildings comprising a transparent or translucent roofing - Google Patents

Abstract

The method consists in collecting solar radiation by means of a film of coloured aqueous solution, trickling over the roofing. The device comprises a tank containing the coloured solution, a circulation pump, a distribution pipe at the top part of the roofing, a switching valve placed on the rainwater pipe allowing return to the tank when the installation is being used and the restoring of the normal rainwater draining circuit when it is not being used. The heat is removed by natural evaporation and, optionally and as a complement, by means of a cooling tower.

Description

 The present invention relates to a method for limiting the heating of buildings subjected to solar radiation. We know that the heating of buildings is due in large part to solar radiation penetrating through the openings.

 To limit the heating of buildings subjected to this radiation, passive means and active means are used.

 Passive means include exterior or interior blinds and projections forming a sun visor. Among the active means are all the air conditioning processes which aim to extract heat from the building.

 The passive means do not apply well to industrial buildings which are most often with overhead lighting.

 The cost of the measures to be taken to limit the extent of overheating therefore leads, in the case of these buildings, to limiting the size of the glazed surfaces on the roof.

 This results in a low level of natural light, leading to the frequent use of artificial lighting, as well as a limitation of solar gain in winter (greenhouse effect), at a period when they are, on the contrary, sought after.

 The method, object of the present invention, is a means both active and passive to limit the heating of buildings in summer, while allowing full use of free solar gain in winter and limit the use of artificial lighting.

To this end, the glazed surfaces, preferably slightly inclined, which constitute all or part of the roofing of the building, are covered with a film of colored solution absorbing solar radiation. This film flows according to a preferentially laminar regime - function of the slope
The supply must be permanent to maintain the continuity of the film.

 The device according to the method therefore preferably comprises a tank for reserving an aqueous colored solution, a circulation pump drawing from the tank, a set of pipes and distributors for supplying the upper areas of the cover from which flows the solution. The colored solution is collected by the rainwater collection system and, suitably referred, returns to the reserve tarpaulin.

 The colored solution film provides passive protection by intercepting all or part of the solar radiation and active protection by removing this heat by evaporation of the solution. This evaporation occurs naturally on the surface of the film and of the reserve sheet.

 The theoretical minimum temperature that can be reached by the film corresponds to the humid temperature of the air, generally several degrees lower than its dry temperature, that indicated by the usual thermometer. To approach the theoretical minimum value, it may be useful to have an atmospheric refrigerant on the circuit where the finely divided solution is cooled by a stream of natural or forced air.

 The energy consumption of such a device is very low, compared to that of a traditional air conditioning installation, since it only includes pumps and fans, to the exclusion of any refrigeration machine.

 The adjustment of the occultation of the solar radiation takes place by acting on the capacity of the solution, and / or on the thickness of the film and (or) on the importance of the zones supplied.

 When it threatens to rain, the installation is stopped and the rainwater drainage system redirected to the usual outlets.

 In winter, the device is stopped and protected against frost, or drained.

 The method, object of the invention making it possible to considerably reduce the solar gains due to the transparent or translucent cover parts, makes it possible to increase the proportion of these up to the point where the cover is completely transparent or translucent.

 This results in the building, in winter and in miserable weather, extreme luminosity at the same time as very significant energy savings, by using - free solar gain.

 The description which follows, with reference to the accompanying drawings by way of nonlimiting examples, will make it possible to understand clearly how the invention can be put into practice.

 Figure 1 is a diagram of the device, object of the invention.

 Figure 2 is a perspective view of the cover of a building equipped with the device object of the invention.

 According to the diagram in FIG. 1, a circulation pump 1 draws the opaque solution from the reserve 2 and feeds, via the pipe 3, a distribution manifold 4. This manifold sprinkles the cover 5 causing film to flow thereon. 6. The solution is collected in the gutter 7 and borrows the first section of a downspout of rainwater 8. A switching valve 9, when the process is used, puts the downspout 8 into communication with a pipe 10.

 In the diagram, this pipe feeds an air cooler composed of an envelope 11, a fan 12, a distribution ramp 13 and runoff surfaces 14, from which the water returns to the tank 2.

 The evaporation which occurs mainly on the roof and in the air cooler, must be compensated by a supply of water provided by the float valve 17.

 In a simplified version, the diagram does not include an air cooler and the pipe 10 returns directly to the cover 2.

 When the device is not used, the routing valve 9 puts the first section 8 into communication with the second section 15 of a downspout connected to the collector 16. When the device is not used, the The evacuation of rainwater therefore takes place in the usual way.

 FIG. 2 represents a typical perspective view of a cover fitted according to the device.

 The transparent or translucent ribbed cover 5, the ridge of which is capped with a sealing cap 18, is watered at its upper part by a distribution ramp 4. The solution is collected by the gutter 7 and led to the first section 8 of the descent of rainwater.

Claims (3)

 1. Method for limiting the heating of buildings provided with partially or completely transparent or translucent covers, by interposing a film of a colored solution 6 flowing freely on the surface of the cover 5.  2. Device using the method according to claim 1, comprising at least one circulation pump 1 drawing the solution from at least one reserve tank 2 to supply at least one distribution ramp 4 situated above the cover to be protected and at least a switch valve 9 arranged on a downspout of rainwater 8 making it possible to orient the solution collected by the rainwater collection system 7 towards the reserve tarpaulin (s) in the position of use of the process and d '' direct rainwater to the usual drainage system 15 and 16 when the installation is not in use.  3. Device according to claims 1 & 2, wherein the solution is cooled additionally by means of an air cooler comprising at least one distribution ramp 13 from which the water flows to return to the reserve tank 2.