Heat transfer apparatus with a variable absorption surface

Abstract

Heat transfer apparatus with a variable absorption surface The heat transfer apparatus comprises a variable absorption surface ( 20 ) interposed between a transparent wall ( 12 ) and an insulating module ( 14 ), said variable absorption surface ( 20 ) being exposed to solar radiation through the transparent wall ( 12 ) and having absorbent regions ( 20 A) and reflective regions ( 20 R), as well as movable shutters ( 22 ) arranged opposite the variable absorption surface ( 20 ) and each having an absorbent side ( 22 A) and/or a reflective side ( 22 R), these shutters being movable between at least one first position and a second position so as to vary the absorbent regions and/or the reflective regions as well as the absorbent sides and/or the reflective sides exposed to solar radiation. The invention applies to the construction sector.

1 . Heat transfer apparatus, comprising a transparent wall ( 12 ) in contact with a first thermal mass (M 1 ) and adapted to be exposed to solar radiation (S), an insulating module ( 14 ) placed between the transparent wall ( 12 ) and a second thermal mass (M 2 ) which is to be heated or cooled, the insulating module ( 14 ) comprising circulation passages ( 16 ,  18 ) for a heat-carrying fluid which does or not permit heat transfer between the first thermal mass (M 1 ) and the second thermal mass (M 2 ),
 characterized in that it comprises a surface with variable absorption ( 20 ;  120 ;  220 ) interposed between the transparent wall ( 12 ) and the insulating module ( 14 ), said variable absorption surface being exposed to solar radiation (S) through the transparent wall ( 12 ) and having absorbent regions ( 20 A;  120 A;  220 A) and/or reflective regions ( 20 R;  120 R;  220 R), as well as movable shutters ( 22 ;  122 ;  222 ) arranged opposite the variable absorption surface ( 20 ;  120 ;  220 ) and each having an absorbent side ( 22 A;  122 A;  222 A) and/or a reflective surface ( 22 R;  122 R;  222 R), these shutters being movable between at least one first position and a second position in order to vary the absorbent regions and/or the reflective regions as well as the absorbent sides and/or the reflective sides exposed to the solar radiation.   
   
   
       2 . Heat transfer apparatus according to  claim 1 , characterized in that the variable absorption surface ( 20 ) has absorbent regions ( 20 A) alternating with reflective regions ( 20 R), in that the movable shutters ( 22 ) each have an absorbent side ( 22 A) and a reflective side ( 22 R) opposite one another, these shutters being movable between a first position, known as the absorbent position, in which the absorbent sides ( 22 A) of the shutters ( 22 ) and the absorbent regions ( 20 A) of the variable absorption surface ( 20 ) are exposed and a second position, known as the reflective position, in which the respective reflective sides ( 22 R) of the shutters ( 22 ) and the reflective regions ( 20 R) of the variable absorption surface ( 20 ) are exposed. 
   
   
       3 . Heat transfer apparatus according to  claim 2 , characterized in that, in the first position, the reflective sides ( 22 R) of the shutters ( 22 ) come to be opposite the reflective regions ( 20 R) of the variable absorption surface ( 20 ) in order to hide them, whereas in the second position the absorbent sides ( 22 A) of the shutters ( 22 ) come to be opposite the absorbent regions ( 20 A) of the variable absorption surface ( 20 ) in order to hide them. 
   
   
       4 . Heat transfer apparatus according to one of  claims 2  and  3 , characterized in that the absorbent regions ( 20 A) and the reflective regions ( 20 R) of the variable absorption surface ( 20 ) are constructed in the form of parallel strips of a selected width (L) extending in a selected main direction, and in that the movable shutters ( 22 ) are mounted to be pivotable about respective axes ( 24 ) parallel to the selected main direction. 
   
   
       5 . Heat transfer apparatus according to  claim 4 , characterized in that the movable shutters ( 22 ) are each capable of pivoting through substantially 180° from the first position to the second position, or vice versa, so that in the first position each shutter ( 22 ) comes to hide a reflective region ( 20 R) of the variable absorption surface ( 20 ) and, in the second position, each shutter ( 22 ) comes to hide an absorbent region ( 20 A) immediately adjacent to said reflective region ( 20 R). 
   
   
       6 . Heat transfer apparatus according to  claim 1 , characterized in that the variable absorption surface ( 120 ) has absorbent regions ( 120 A) alternating with reflective regions ( 120 R), in that the movable shutters ( 122 ) each have a reflective side ( 122 R) and are movable in translation between a first position in which the reflective sides ( 122 R) of the shutters ( 122 ) and the reflective regions ( 120 R) of the variable absorption surface ( 120 ) are exposed and a second position in which the reflective sides ( 122 R) of the shutters ( 122 ) and the absorbent regions ( 120 A) of the variable absorption surface ( 120 ) are exposed. 
   
   
       7 . Heat transfer apparatus according to  claim 1 , characterized in that the variable absorption surface ( 120 ) has absorbent regions ( 120 A) alternating with reflective regions ( 120 R), in that the movable shutters ( 122 ) each have an absorbent side ( 122 A) and are movable in translation between a first position in which the absorbent sides ( 122 A) of the shutters ( 122 ) and the reflective regions ( 120 R) of the variable absorption surface ( 120 ) are exposed and a second position in which the absorbent sides ( 122 A) of the shutters ( 122 ) and the absorbent regions ( 120 A) of the variable absorption surface ( 120 ) are exposed. 
   
   
       8 . Heat transfer apparatus according to  claim 1 , characterized in that the variable absorption surface ( 220 ) has absorbent regions ( 220 A) spaced in pairs and arranged obliquely relative to a selected direction (D) and in that the movable shutters ( 222 ) are arranged obliquely and each have a reflective surface ( 222 R) and are movable in translation in said given direction (D) between a first position in which the absorbent regions ( 220 A) of the variable absorption surface ( 220 ) are exposed and a second position in which the reflective sides ( 222 R) of the shutters ( 222 ) are exposed. 
   
   
       9 . Heat transfer apparatus according to  claim 1 , characterized in that the variable absorption surface ( 220 ) has reflective regions ( 220 R) spaced in pairs and arranged obliquely with respect to a selected direction (D) and in that the movable shutters ( 222 ) are arranged obliquely and each have an absorbent side ( 222 R) and are movable in translation in said given direction (D) between a first position in which the reflective regions ( 220 R) of the variable absorption surface ( 220 ) are exposed and a second position in which the absorbent sides ( 220 A) of the shutters ( 222 ) are exposed. 
   
   
       10 . Heat transfer apparatus according to one of  claims 1  to  9 , characterized in that the absorbent regions ( 20 A;  120 A;  220 A) of the variable absorption surface ( 20 ;  120 ;  220 ) and the absorbent sides ( 22 A;  122 A;  222 A) of the shutters ( 22 ;  122 ;  222 ) are dark in colour, particularly black, while the reflective regions ( 20 R;  120 R;  220 R) of the variable absorption surface ( 20 ;  120 ;  220 ) and the reflective sides ( 22 R;  122 R;  222 R) of the shutters ( 22 ;  122 ;  222 ) are light in colour, particularly white. 
   
   
       11 . Heat transfer apparatus according to one of  claims 1  to  10 , characterized in that it comprises an actuator ( 28 ) for moving the shutters ( 22 ;  122 ;  222 ) in synchronism. 
   
   
       12 . Heat transfer apparatus according to one of  claims 1  to  11 , characterized in that the circulation passages ( 16 ,  18 ) for the insulating module ( 14 ) allow natural circulation of the heat-carrying fluid. 
   
   
       13 . Heat transfer apparatus according to  claim 12 , characterized in that the circulation passages comprise:
 first circulation channels ( 16 ) connecting an external space ( 26 ) for heat-carrying fluid located between the transparent wall ( 12 ) and the variable absorption surface ( 20 ;  120 ) and an internal space ( 30 ) for heat-carrying fluid arranged in contact with the second thermal mass (M 2 ), these first circulation channels terminating in absorbent regions ( 20 A;  120 A) of the variable absorption surface and passing upwardly through the insulating module ( 14 ) from the absorbent regions; and   second circulation channels ( 18 ) connecting the external space ( 26 ) for heat-carrying fluid and the internal space ( 30 ) for heat-carrying fluid, these second circulation channels terminating in reflective regions ( 20 R;  120 R) of the variable absorption surface ( 20 ;  120 ) and passing downwardly through the insulating module ( 14 ) from the reflective regions;   so that, in an absorbent position of the shutters, the first circulation channels ( 16 ) are open, while the second circulation channels ( 18 ) are closed and that, in a reflective position of the shutters, the first circulation channels ( 16 ) are closed, while the second circulation channels ( 18 ) are open.   
   
   
       14 . Heat transfer apparatus according to  claim 13 , characterized in that:
 in the absorbent position of the shutters, natural circulation of the heat-carrying fluid takes place only if the temperature of the heat-carrying fluid in the external space ( 26 ) is greater than the temperature of the heat-carrying fluid in the internal space ( 30 ), thus permitting heat transfer from the external space to the internal space, and   in the reflective position of the shutters, natural circulation of the heat-carrying fluid takes place only if the temperature of the heat-carrying fluid in the external space ( 26 ) is below the temperature of the heat-carrying fluid in the internal space ( 30 ), thus permitting heat transfer from the internal space to the external space.   
   
   
       15 . Heat transfer apparatus according to one of  claims 1  to  14 , wherein the second thermal mass (M 2 ) is a generally vertical wall of a building, characterized in that said transfer apparatus ( 10 ) is arranged in a generally vertical direction along the wall of the building, the transparent wall ( 12 ) and the insulating module ( 14 ) extending in said direction. 
   
   
       16 . Heat transfer apparatus according to one of  claims 1  to  14 , wherein the second thermal mass (M 2 ) is an internal wall ( 32 ) arranged below a roof (T) with a selected slope, characterized in that the transparent wall ( 12 ) of the apparatus is provided so as to integrate in the slope of the roof, while the insulating module ( 14 ) is adapted to extend in a generally vertical direction. 
   
   
       17 . Heat transfer apparatus according to  claim 16 , characterized in that it comprises at least one heat conducting element ( 34 ) connected in heat contact with the internal wall ( 32 ) and arranged along the insulating module ( 14 ) opposite the variable absorption surface ( 20 ). 
   
   
       18 . Heat transfer apparatus according to one of  claims 1  to  11 , characterized in that the circulation passages ( 40 ,  42 ) of the insulating module ( 14 ) permit forced circulation of the heat-carrying fluid. 
   
   
       19 . Heat transfer apparatus according to  claim 18 , characterized in that the circulation passages comprise two openings ( 40 ,  42 ) passing through the insulating module ( 14 ), one of which ( 42 ) is provided with a controlled-operation fan ( 44 ), and provides communication between an external space ( 26 ) located between the transparent wall ( 12 ) and the variable absorption surface ( 20 ) and defining a U shaped circulation pathway for the heat-carrying fluid, and an internal space ( 30 ) arranged in contact with the second thermal mass (M 2 ) and defining a U-shaped circulation pathway for the heat-carrying fluid, the fan ( 44 ) being capable of being put selectively into at least one of the following states:
 an open state that allows heat-carrying fluid to circulate between the external space ( 26 ) and the internal space ( 30 ) and thus permits heat transfer between the first thermal mass (M 1 ) and the second thermal mass (M 2 ); and   a closed state that prevents heat-carrying fluid from circulating between the external space ( 26 ) and the internal space ( 30 ) and thus prevents heat transfer between the first thermal mass (M 1 ) and the second thermal mass (M 2 ).   
   
   
       20 . Heat transfer apparatus according to one of  claims 1  to  19 , characterized in that the heat-carrying fluid is air.