FR3038972A1 - SOLAR ENERGY SENSOR AND HOT AIR HEATING DEVICE HAVING SUCH A SENSOR - Google Patents

Abstract

Solar heat energy sensor comprising a box (2) having a wall (1) permeable to solar radiation (10), an insulating bottom (7), a peripheral frame (21) and a wall internal partition (3) extending under the upper wall (1) and sharing the box (2) between a closed space (4) on the side of the upper wall (1) and a space (5) forming a circulation duct of air to warm; this inner wall (3) transmits the heat of the solar radiation (10) to the air circulation space (5) and the latter contains an absorber (6) of this transmitted heat, which absorber (6) consists of at least one perforated metal structure (16) in the form of open honeycombs through which the air is able to circulate.

Description

Solar energy sensor and hot air heater comprising such a sensor

The present invention relates to a solar energy sensor and a hot air heating device comprising such a sensor.

The technical field of the invention is that of the manufacture and installation of sensors capable of absorbing and using the heat of the solar radiation by transmitting it to a fluid, which is air in the present invention, circulating in the sensor.

We already know such sensors that are available on the market, especially since the 1970s because of the then sharp increase in the price of oil and gas, the political will to protect the environment and save non-renewable energy and of individual considerations, both economic and ecological, which are pushing more and more to develop techniques for exploiting renewable energies such as those received directly from the sun.

For example, among the oldest French patent applications filed more than thirty years ago, in the field of air circulation solar energy sensors, the patent application FR2536156 filed November 12, 1982 by Alternative Research Institute Synopsis: this document describes a solar heat energy sensor of the type comprising a box having a front face receiving at least one wall permeable to solar radiation and a bottom carrying a wall constituting an absorber of this solar energy, these two walls defining a space in which circulates air (or another gas) which is heated in contact with the absorber which restores the calories it has captured; in one embodiment, inside the box, under and parallel to the front wall permeable to solar radiation, it can be mounted a second wall permeable to solar radiation, these two walls then being separated by an interval which constitutes a mattress insulating air; the invention described in this document is however very different from the present invention because it relates to a heat exchanger included in said box and in which circulates a heat transfer fluid which is heated by air (or any other gas) itself heated in contact with the absorber and circulating in closed circuit in a specific manner in the sensor box.

One can also cite the patent application FR2975759 more recent, because filed May 26, 2011 by the company Systovi, and which has for object a thermal solar collector with air circulation constituted by a box formed by a bottom, a peripheral side wall and an upper wall transparent to the light, said box containing a wall, absorbing the transmitted heat, extending under the upper wall, at a distance from the latter, for delimiting on the one hand, with said upper wall, a blade immobile still air (as already described in fact in the earlier application cited above) and on the other hand with the bottom of the box a volume called circulation in which the air will heat up (as also in the previous application cited above, but here not in closed circuit to heat another fluid circulating in a heat exchanger but in open circuit): and to help the air to load in calories, the bottom of the box means deviating the air flowing to the energy absorbing means, namely the intermediate wall extending under the upper wall, away from it.

However, despite this configuration and these air deflection means, the efficiency of such sensors is not satisfactory. Other manufacturers have also developed other techniques to improve this performance and filed patent applications, some of which are even older than the first mentioned above as Application for Certificate of Addition FR2400167 filed May 30, 1978 by US Union Carbide Corporation which teaches a solar energy air heater comprising: a housing having a front wall for transmitting incident solar rays and having an inlet and an outlet forming a circulation path of a gas to be heated; - a radiation-absorbing and gas-permeable collector disposed transversely to the gas flow path in the housing and for receiving incident solar rays through the front wall, and transferring the absorbed heat to the gas; passing along the circulation path and through the collector element and - a radiation trap placed in the b close to the surface of the front wall and having a cellular structure comprising a plurality of open cells communicating with the circulation path and having walls which are substantially perpendicular to the front wall and which constitute partitions preventing the flow of gas through the trap in a direction substantially parallel to the plane of the front wall, the cellular structure being formed of a material capable of transmitting light and which is opaque to the infrared rays emitted by the collecting element towards the front wall.

However, despite this collector element and radiation trap independent of each other, the performance of such sensors is not satisfactory either, while these sensors are quite complex and therefore expensive; moreover, they are not marketed at least in France to date, thirty-seven years after the filing of this application for a certificate of addition.

However, we can usefully refer to these documents as well as many other patent applications filed on this type of air-circulating solar energy sensors, also called aerothermal solar collectors, and which constitute a family in which can be attached the present invention; we will not repeat here the description of the principle of operation of these different processes and existing devices for which we can consider that the present application provides improvements.

The problem is, firstly, to improve the efficiency of such types of air-circulating solar energy sensors, secondly, to achieve them at a lower cost, both of these objectives being able to ensure a satisfactory development. commercial thanks to a rapid return on investment, and thirdly to be able to install a complete and integrated hot air heating system of a building comprising and using such sensors.

A solution to the problem posed is a solar heat energy sensor comprising, in a manner known for more than thirty years, a box with a so-called upper wall, permeable to solar radiation, an insulating bottom closing the box at its lower part, a peripheral frame and an inner wall extending under the upper wall and sharing the box between a closed space on the side of the upper wall and a space forming an air circulation duct to and, according to the invention, this internal wall transmits the heat of the penetrating solar radiation through the upper wall to the air circulation space and the latter contains an absorber of this transmitted heat, which absorber is consisting of at least one perforated metal structure in the form of open honeycombs and through which the air is able to circulate.

The objectives of the present invention are also achieved with a building hot air heating device using solar heat energy and comprising: at least one solar energy sensor, which is arranged outside the building, in which circulates air, entering this solar energy sensor and taken outside the building, towards the interior of the building and which is a sensor according to the definition given above and completed hereafter, - a circulation fan of this air, - an indoor air temperature sensor of the building, - an air temperature sensor at the output of the solar energy sensor, and - a fan control regulator.

In a preferred embodiment, the perforated metal structure is made from a continuous metal film cut in dotted lines along lines parallel to a single direction, the so-called dotted lines of two adjacent parallel lines being positioned in staggered rows, which film is then stretched perpendicularly to the parallel lines of cuts, which cuts, deforming, open and form cells that constitute the honeycomb structure, adapted to allow air circulation.

In a preferred embodiment, the heat absorber consists of several superimposed layers of metal films, stretched into open honeycomb shaped structures, all of these layers completely filling the air circulation space. and being adapted to allow said circulation through the open cells and along the uncut portions of the metal films.

Such provisions and features, as well as with those complementary described below, respond to the problem; in fact and in particular tests have shown, under the same operating conditions, namely a flow rate of 80 m3 / hour provided by the same fan, a sunshine of 1000 Watt / m2 and a surface of 1.5 m2, the following yields: on the one hand with a sensor made according to characteristics known to date (as for example described in the patent applications cited above), a difference in temperature of the air between the inlet and the the output of the solar energy sensor from 20 to 25 ° C, and - on the other hand with a sensor according to the present invention, with three superposed layers of metal films, stretched into open honeycomb shaped structures and crossed, and occupying all the air circulation space to be heated, but without of course be tight and create a significant loss of load that would curb the said air flow, the said space being (to accommodate these three layers of metal film drawn and having the characteristics given below by way of example in the explanation of their manufacture) with a width of about 750 mm, a thickness of about 20 mm and a length of about 2000 mm an air temperature difference is obtained between the inlet and the outlet of the solar energy sensor according to the invention of 58 ° C.

These results speak for themselves, and the goal of achieving such sensors at lower cost is also achieved because the manufacture of honeycomb shaped open structures from continuous metal films cut in parallel dotted lines and in quinconces, which film is then stretched perpendicular to the parallel lines of cuts, is inexpensive and fast.

The result is: - a new solar energy sensor which on the one hand transforms the energy of the sun's rays into calories stored in an innovative absorber and on the other hand thanks to this same absorber gives back these calories, with an unequaled yield and optimum for a solar collector aerothermal, in ambient air, and - a new hot air heating device comprising such a solar energy sensor.

Which solar energy sensor and which heating device respond to the problem, and the advantages mentioned above and completed in the description of the figures below prove the interest. The description and the accompanying figures give an example embodiment but other embodiments are possible within the scope of the present invention.

Figure 1 is an overall diagram of a hot air heater according to the invention and the dashed lines connecting the control controller 11 to all other components of the device there represent the electrical connections therewith.

Figure 2 is a sectional view along II, 11 'of Figure 1 of the solar energy sensor alone according to the invention.

Figure 3 is a cross-sectional view of the solar energy sensor according to the invention as in Figure 2 but in perspective view and in an angle.

FIG. 4 is a top plan view of a pre-cut metal film before deformation in order then to carry out, by stretching, the honeycomb metal structure of the sensor according to the invention, and as represented in FIG. 5.

As indicated above, the solar heat energy sensor comprises, in a known manner, a box 2 provided with: a so-called upper wall 1, permeable to the solar radiation 10 that it receives, when the box 2 of the solar energy sensor is disposed horizontally or inclined on any surface such as the roof of a building whose internal volume is to be heated, - an insulating base 7 closing the box 2 at its lower part, - a peripheral frame 2i and - an inner wall 3 extending under the upper wall 1, held and fixed at a given distance from it for example by a peripheral seal 25, and sharing the casing 2 between a closed space 4 on the side of the upper wall 1 and a space 5 forming an air circulation duct to be heated.

According to the invention, this inner wall 3, which is preferably a steel alloy sheet with a thickness of 3 to 5/10 °, preferably 4/10 ° mm, and whose face turned towards the upper wall 1 is black and the one facing the air circulation space 5 is instead radiating, transmits the heat of the solar radiation 10 penetrating through the upper wall 1 to the air circulation space 5.

In addition, this air circulation space 5 contains an absorber 6 of this transmitted heat, which absorber 6 consists of at least one perforated metal structure 16 in the form of open honeycomb 26 through which the air is able to move.

According to the representation of Figures 2 and 3, it is noted that it is difficult to represent in section and perspective the shape of open honeycomb 26 of the metal structure 16 which is the innovative absorber 6 solar heat, transmitted by the inner wall 3.

The shape of this perforated metal structure 16 will undoubtedly be better understood by describing how it is produced and as represented in FIGS. 4 and 5: - it is cut out according to a dotted line, preferably 9 mm long (i) every 3 mm (e), a continuous metal film and planar 16, preferably aluminum alloy and thickness of about 0.7 mm, along lines parallel to a single direction and spaced 1.5 mm (p the so-called dotted lines of two adjacent parallel lines being positioned in staggered rows so that a dot cut out on a line is framed by two uncut portions of the two adjacent lines, and vice versa, the film is then stretched perpendicular to the parallel lines of cutouts, which cuts, by deforming, open by twisting uncut portions and form cells 26 which constitute the honeycomb structure which promote the heat exchange of air which circulates in this structure and that warms all the better. The absorber 6 is preferably composed of several superimposed layers, such as three as in the aforementioned tests, of metal films 16 drawn into open honeycomb shaped structures: these superimposed layers best fulfill the space of air circulation 5, while being able to allow the said circulation without braking, through firstly the open cells 26 formed at the dotted cutouts, by the deformation of the film and secondly along uncut parts which transmit to it the absorbed heat; this circulation of air can thus be done both in the perpendicular direction and in the direction parallel to the cutting lines when the superposed layers are arranged by crossing alternately and perpendicularly, during their superposition on one another, their clean lines of cutouts.

The bottom 7, which isolates the casing 1 from the side opposite to the upper wall 1 receiving the radiation 10 from the sun and permeable thereto, and which delimits the air circulation space 5, can be constituted by a panel "Sandwich" 7 having at least two sheets of aluminum between which is disposed an insulating material.

Such a solar energy sensor according to the invention consists solely of 100% recyclable elements and can be positioned in any position (portrait or landscape) and on any location (roof, facade, ground, to flat, inclined).

It can be integrated, alone or with other sensors mounted one after the other in series and / or in parallel depending on the desired outlet temperature and air flow, in a complete building heating device using the solar heat energy, as shown schematically in Figure 1, and comprising: at least therefore such an external sensor 2 of solar energy in which air circulates, taken outside the building, inwardly 22 thereof, - a fan 14 for circulating this air, - a sensor 13 of the indoor air temperature 22 of the building, - a sensor 12 of the air temperature at the output of the sensor 2, and - a regulator 11 of the fan 14, and powered by a power supply 20. The circulation space 5 of the air to be heated in said sensor according to the invention comprises a fresh air inlet 8 equipped with a filter type dust and an outlet 9 adapted to be r granted either to the air intake of another sensor, or to a ventilation duct 24 connected to an air intake module, containing the fan 14, which sends the hot air into any volume 22 that the we want to warm up, like that of the said building.

The complete building heating device described above may also be connected, by a bypass 27 opening after the air circulation fan 14, to a duct 28 containing an air-water heat exchanger 21 in which then circulates on one side the air thus coming from the outlet 9 of the sensor 2 and the other of the domestic water 23 from a hot water tank 19 where it returns there.

To activate the opening of this bypass 27 the device comprises a motorized shutter 17 which is adapted to direct the hot air to the conduit 28 containing the air-water heat exchanger 21, and a water circulator 15 engages when the flap 17 is open towards the bypass 27 and therefore towards this exchanger 21.

For this, the control regulator 11 then drives not only the fan 14 but also the operation of all the elements of the device according to the invention, so that: the fan 14 is switched on or off according to a part of the measured ambient temperature 13 in the building 22 with respect to high and low data set values, and secondly of the measured temperature 12 at the output 9 of the solar energy sensor 2, however-even if the ambient temperature 13 is reached, the fan can continue to run if the measured temperature 18 of the domestic hot water tank is less than a set value, and in this case the motorized shutter 17 opens and the water circulator 15 is started, - when the measured temperature 18 of the domestic hot water tank reaches the set point, and / or, according to the priority given to one or the other, when the measured ambient temperature e 13 in the building 22 goes down below the given low setpoint value, the motorized shutter 17 returns to its initial position to direct the hot air towards the interior 22 of the building and the water circulation pump 15 stops, when the two high setpoint temperatures are reached both in the building 22 and the hot water tank 19, the fan 14 and the water circulator 15 are no longer powered and are thus stopped, and the motorized shutter 17 returns anyway to its original position.

Claims (9)

Solar heat energy sensor comprising a box (2) with a wall (1) said upper, permeable to solar radiation (10), an insulating base (7) closing the box (2) to its part said lower, a peripheral frame (2i) and an inner wall (3) extending under the upper wall (1) and sharing the box (2) between a closed space (4) on the side of the upper wall (1) and a space (5) forming an air circulation duct to be heated, characterized in that said inner wall (3) transmits the heat of the solar radiation (10) penetrating through the upper wall (1) to the space (5) for circulating air and the latter contains an absorber (6) for this transmitted heat, which absorber (6) is constituted by at least one perforated metal structure (16) in the form of nests. open bees through which the air is able to flow. 2- energy sensor according to claim 1 characterized in that the perforated metal structure (16) is made from a continuous metal film cut in dotted lines along lines parallel to a single direction, the so-called dotted lines of two lines adjacent parallels being positioned in quincunxes, which film is then stretched perpendicular to the parallel lines of cuts, which cuts, deforming, open and form cells (26) which constitute the honeycomb structure, adapted to allow a circulation of air. 3- energy sensor according to claim 2 characterized in that the absorber (6) consists of several superimposed layers of metal films (16) drawn into open honeycomb shaped structures, filling the space of air circulation (5) and able to allow said flow through the cells (26) open and along the uncut portions of the metal films (16). 4- energy sensor according to any one of claims 1 to 3 characterized in that the inner wall (3) heat transmitter is a steel alloy sheet 3 to 5/10 ° thick whose face turned towards the upper wall (1) is black. 5- energy sensor according to any one of claims 1 to 4 characterized in that the bottom (7), insulating the box (1) and defining the space (5) of air circulation, is constituted by a sandwich panel (7) having at least two sheets of aluminum between which is disposed an insulating material. 6- energy sensor according to any one of claims 1 to 5 characterized in that the circulation space (5) of the air to be heated comprises a fresh air inlet (8) and an outlet (9) adapted to be connected either to the air intake of another sensor or to a ventilation duct (24) connected to an air intake module (14) which sends the hot air into any volume ( 22) that we want to warm up. 7- A building hot air heating device using solar heat energy and comprising at least one outdoor solar energy sensor (2) in which air circulates to the inside (22) of the building, a fan ( 14), an indoor air temperature sensor (13) of the building and an air temperature sensor (12) output from the sensor (2) and a control regulator ( 11) of the fan characterized in that the solar energy sensor (2) is a sensor according to any one of claims 1 to 6 and the incoming air (8) therein is taken outside the building . 8- Device according to claim 7 characterized in that it is connected to an exchanger (21) of air-water heat in which flows on one side the air output of the sensor (2) and the other side of the sanitary water (23). 9- Device according to claim 8 characterized in that it comprises a motorized shutter (17) which is adapted to direct the hot air to the air-water heat exchanger (21) and a water circulator (15) which when the flap is open towards this exchanger (21).