IT202100005219A1 - WALL WITH VARIABLE THERMAL TRANSMITTANCE - Google Patents

Description

Patent application for industrial invention entitled:

?VARIABLE THERMAL TRANSMITTANCE WALL?

FIELD OF THE INVENTION

The present invention relates to techniques for making adaptive walls that change their properties? thermophysical according to the internal comfort conditions required and the external environmental conditions, with consequent significant energy savings.

PRIOR NOTE TECHNIQUE

As far as the knowledge of the inventors is concerned, there is no similar proposal in the building panorama, as no variable thermal transmittance system is yet available, with the exception of devices which include walls with modifiable air spaces, but whose effect on the variation of the properties? overall thermal insulation is limited and with low capacity? control. SUMMARY OF THE INVENTION

The present invention relates to techniques for making walls with dynamic thermal behaviour, i.e. walls for buildings which are capable of varying their capacities? of thermal insulation according to the temperatures outside and inside the buildings. This property? ? obtained through the embedding in any horizontal, vertical or oblique wall, made of any material, of pipes made of plastic, metal or other materials normally used for the transport of liquids, inside which flows a heat transfer fluid moved by a thrust member such as a pump, whose function is to transport heat in the direction of the thickness of the wall, from the inside to the outside and vice versa.

The problem that the invention aims to solve? is to create adaptive walls that change their properties? thermophysical conditions according to the internal comfort conditions required and the external environmental conditions, with negligible energy expenditure and in any case considerably lower than the energy savings achieved. System check? linked to two temperature sensors, one placed in the external environment and one placed inside: their differential value guides the switching on and off of the pusher or pump.

If in the winter season the walls are generally much more? performing how much greater? their ability? of thermal insulation, in the intermediate seasons and in the summer the physics of the building is more? complex.

In late autumn and early spring, solar radiation can heat the external surfaces of the walls and the heat can? be transported immediately inside buildings, providing ambient heating.

In summer, for a non-negligible part of the day (especially at night), the outside temperature is ? lower than the internal set point for thermal comfort. During these periods, the transmission of heat (from inside to outside) is facilitated by the device, which drastically reduces the thermal insulation of the wall.

When the thrust organ (pump) ? switched off, the wall behaves thermally like a traditional wall.

The object of the present invention is achieved thanks to an adaptive wall comprising, embedded inside the wall, a duct which develops more in the uppermost layer. inside the inner wall and in the layer pi? exterior of the outer wall. Inside the duct ? present a heat transfer fluid that normally ? still in the condition of rest and ? free to move and circulate inside the duct thanks to a push member. The thrust organ? designed to move the fluid from its rest condition to make it flow inside the duct. A first internal surface temperature probe and a second external surface temperature probe are provided in the wall which are positioned embedded, respectively in the uppermost layer. inside the inner wall and in the layer pi? exterior of the outer wall to measure the internal and external temperature. The adaptive wall also includes a control unit which acquires the data measured by the first and second temperature probes, compares them and commands the pusher to leave the heat transfer fluid stationary or flow depending on the result of this comparison between the indoor temperature and outdoor temperature.

In embodiments the wall ? made of any material and the two layers where ? drowned the pipe that makes the conduit are made of high conductivity material? thermal.

In various embodiments, the high conductivity material is thermal ? chosen from plasterboard, concrete and other building materials of similar conductivity? thermals. Furthermore, preferably the adaptive wall comprises an outer wall, an intermediate wall which can understand in turn one or more? layers, and an inner wall. In various embodiments, the internal temperature probe ? positioned in the center of the wall away from thermal bridges and away from heat sources and ? drowned inside the inner wall.

Similarly also the external temperature probe ? positioned in the center of the wall possibly in correspondence with the internal temperature probe, also away from thermal bridges and protected from rain and is? drowned inside the external wall.

Preferably, the pipes that form the duct have a part of the trajectory that is in the vicinity of the external wall and a part of the trajectory that is in the vicinity of the external wall. of the inner wall.

Preferably, but not necessarily, the pipes forming the conduit have a serpentine trajectory or a round-trip development.

In some embodiments the adaptive wall ? divided into more parts each crossed by an independent duct trajectory, and there is a thrust member for each part of the wall.

Alternatively, a single pusher and manifold system has been associated with control of each trajectory at the manifold V-valve.

In some variants ? is it possible to provide that the control unit also works with mode? Proportional-Integral-Derivative type adjustment system which optimizes the on/off times of the pusher according to the heat transfer in the desired direction.

In various embodiments, does the thrust member ? chosen between a pump with a fixed number of revolutions, a pump with three speeds of rotation, or a body equipped with an inverter which allows you to vary it continuously? the characteristic curve.

Preferably, the pipes forming the conduit are made of a material selected from plastic, copper, iron.

The heat transfer fluid? chosen between pure water and water added with other substances such as additives, in particular glycol which inhibits freezing.

The additive ? with variable percentages between 10% and 40% depending on the climatic zone in which the device is installed.

Temperature probes (Tpi, Tpe) are thermocouple probes, in particular T-type probes with constantan copper junction.

The duct has a continuous exchange path in which the pipe alternates internal sections contained in the internal wall with external sections contained in the external wall (PE), in which there are connecting sections between the internal sections and the external sections.

In some embodiments the conduit has a spiral path from the periphery to the center and from the center to the periphery in both the inner wall and the outer wall.

BRIEF DESCRIPTION OF THE FIGURES

Further characteristics and advantages of the invention will become apparent from reading the following description provided by way of non-limiting example, with the aid of the figures illustrated in the attached tables, in which:

- Figure 1 shows an example of a perspective view of a wall according to the invention,

- Figures 2 show implementation details of the wall of Figure 1, - Figure 3 shows a flow chart of the functioning algorithm of the wall,

- Figure 4 shows an example of an embodiment,

Figure 5 shows an example of an embodiment with multiple walls, e

- Figures 6, 7 and 8 show some alternative embodiments.

The parts according to the present description have been represented in the drawings, where appropriate, with conventional symbols, showing only those specific details which are pertinent to the understanding of the embodiments of the present invention, so as not to highlight details which will be immediately apparent, to those skilled in the art. skilled in the art, with reference to the description reported herein.

DETAILED DESCRIPTION OF THE INVENTION

The solution described here is based on techniques for creating adaptive walls that vary their properties? thermophysical conditions according to the internal comfort conditions required and the external environmental conditions.

Technology ? extremely simple, since it is a conduit crossed by a fluid and a small pump connected to a control system that allows it to operate when necessary. The fluid flowing in the duct can? be simply water, but a mixture of water with added glycol is more suitable for preventing the fluid from freezing during the winter.

The installation consists in placing a series of pipes in the walls to cover the surface of the walls and ? executable by a plumber; the electronic part requires you to connect the temperature probes with the pump and with the control unit. The main areas of application are all new buildings and all constructions for which ? possible to intervene on the internal and external side of the enclosure.

The operating logic will come? now described with reference to Figure 2, where all the components that make up the solution proposed here can be identified.

The solution provides for the use of a conduit or a pipe 1 embedded in the wall which puts the lowest layer in thermal communication. interior SI of the wall with its layer pi? external SE.

The wall P in its entirety can? be made of any material, as long as? the two layers where ? drowned the pipe 1 that makes the conduit, or the pi? external SE and the one pi? inside SI are made of high conductivity material? such as, for example, plasterboard or concrete. In particular, the wall P comprises an external wall PE, an intermediate wall PM, which can also be formed by pi? of a layer, and an inner wall PI.

Inside the duct or pipe 1 ? present a fluid 2 that normally ? in the condition of rest and pu? be made to flow inside the pipe 1 thanks to a movement pump 5. The movement pump 5 pushes the fluid 2 and makes it flow inside the pipe 1.

Furthermore, two surface temperature probes 3 are provided, one internal Tpi and one external Tpe to be positioned, drowning them, respectively in the layer SI pi? interior of the wall, i.e. in the internal wall Pi, and in the SE layer pi? outside of the wall, i.e. in the external wall PE of the wall P.

In preferred embodiments, the Tpi probe will have to? be positioned inside the room, in the center of the wall, away from thermal bridges (for example fixtures, balconies, windows or window sills) and away from heat sources (radiators, fireplaces, stoves, convectors); embedding a few millimeters inside the inner wall PI guarantees its effectiveness.

In a similar way, also the Tpe probe will have to? be positioned outside the building, in the center of the external PE wall, possibly in correspondence with the Tpi probe, away from thermal bridges and protected from rain; embedding a few millimeters inside the external PE wall guarantees its effectiveness.

? a control unit 4 is also provided which acquires the data measured by the two temperature probes Tpi and Tpe and which consequently controls the switching on and off of the movement pump 5.

With reference to the block diagram of Figure 3, ? It is necessary to distinguish operation in the hot summer season from that in the cold winter season. In a step 10 the temperature probes 3 Tpi and Tpe respectively measure the internal temperature Ta and the external temperature Tb.

In a step 20 the control unit 4 reads the temperatures Ta and Tb measured by the temperature probes 3 Tpi and Tpe.

In a step 30, in the case of a winter period, the control unit 4 makes a comparison between the two temperatures Ta and Tb measured by the probes Tpi and Tpe. If the external temperature Tb measured by the probe Tpe is lower than or equal to the internal temperature Ta measured by the probe Tpi, in a step 35 the movement pump 5 is kept off. If the external temperature Tb measured by the probe Tpe is higher than the internal temperature Ta measured by the probe Tpi, in a step 40 the movement pump 5 is turned on and the fluid 2 is made to flow inside the pipe 1 which forms the duct. Both from step 35 and from step 40 the control returns to step 20, for example every 5 minutes, to define the new condition evolved over time.

In a step 50, relating to the summer period, the control unit 4 makes a comparison between the two measured temperatures Ta and Tb measured by the probes Tpi and Tpe. If the external temperature Tb measured by the probe Tpe is lower than the internal temperature Ta measured by the probe Tpi, in a step 55 the movement pump 5 is turned on and the fluid 2 is made to flow inside the pipe 1. In case the temperature temperature Tb measured by the probe Tpe is greater than or equal to the internal temperature Ta measured by the probe Tpi, in a step 60 the movement pump 5 is kept off. Both from step 55 and from step 60 the control returns to step 20, for example every 5 minutes, to define the new condition evolved over time.

In the cold winter season, as long as the temperature Tb of the external wall PE remains lower than that of the internal wall Pi, the pump 5 is inactive and wall P behaves from the point of view of thermal insulation like a classic insulating wall. When the two temperatures are inverted, i.e. when the temperature Tb of the external wall PE becomes higher than the internal one Ta for any reason (arrival of solar radiation, increase in air temperature in hot climates and away from winter minimums), the pump 5 is activated since? one has every interest in transferring the heat from the outside to the inside. The starting input to the pump 5 is given by the control unit 4, following the reading of the internal temperatures Ta measured by the probe Tpi and external Tb measured by the probe Tpe. With the pump 5 in operation, the fluid 2 flows in the pipe 1 and becomes the heat carrier from the outside to the inside.

In summer, the operating principle? exactly the same, except for the mode? start-up of pump 5, which is activated only when the temperature Tb of the external wall PE ? lower than the temperature Ta of the internal wall PI, since? in the hot season the heat must be transported from the inside to the outside.

The diameter of the pipes 1 pu? assume any value and the path of the same pipes pu? go in any direction, as long as? there is a part of the trajectory that is in the vicinity of the external wall PE and a part of the trajectory that is in the vicinity? of the inner wall PI.

An example of a first trajectory? illustrated in Figure 2, while a second type of trajectory different from the first, ? shown in Figure 4.

The closed path of pipe 1 can? be applied to a portion of a wall, an entire facade or the entire envelope of a building.

In the case of subdivision of the walls of a building in pi? parts, each crossed by an independent loop, you can? use a pusher or pump 5 for each subdivision as in Figure 2, or a single pump 5a and a DC manifold system with the control of each loop on the DC manifold valve V (as in domestic heating manifold systems, Figure 5).

The control unit 4, pu? also work with mode? PID (Proportional-Integral-Derivative) type regulation or other types, which in any case optimize the switch-on and switch-off times of pump 5 or 5a according to the fixed objective, i.e. heat transfer in the desired direction. The optimization of the control system lies in the application of functionalities? aimed at quantifying the inertia phenomena inherent in the structure. In other words, c?? the need? not only to set a threshold for switching on and off the pump 5, 5a on the temperature difference Ta and Tb measured by the internal probes Tpi and external probes Tpe but also to analyze the trend of this difference over time so? to predict the eventual change of state of the pump. The PID system through the time evolution of the input signals tries to activate or switch off the operating pump in a predictive way with respect to the simple threshold condition so? to optimize the desired heat transfer.

The thrust member or pump 5 can? be of various kinds: with a fixed number of revolutions or with three rotation speeds or still it can? be equipped with an inverter that allows you to vary it with continuity? the characteristic curve.

However, it is any pump already? existing on the market, such as those, for example, for moving the heat transfer fluid in radiant floor systems.

The pipes 1 can be made of any material (plastic, copper, iron, etc..).

Do pipes made of metallic material (for example steel or copper) have high conductivity? thermal and therefore make it more? the entire proposed system is efficient. Plastic material pipes (e.g. polyethylene or PVC) are less conductive, but more? light and cheap.

The heat transfer fluid 2 can? be water or any other substance. In areas where it is expected to reach outside temperatures below 0?C, ? an additive (for example glycol) is required to inhibit freezing, with percentages varying between 10% and 40% depending on the climatic zone in which the device is installed. The flow rate of the fluid 2 reach any value and render? all the more effective the system all the more? will be high, in any case seeking a compromise between the benefits obtained and the energy expended for pumping.

The temperature sensors can be of any type, as long as? suitable for measuring the expected values for each specific application. The application in question does not require high accuracies, typical of resistance thermometers, but the accuracies which characterize thermocouple type probes are sufficient. There are different types of thermocouple probes that are sensitive within a certain temperature range. T-type probes (constantan copper junction) generally have a measurement range between -200 and 200°C, a range which largely includes the temperatures relating to the phenomenon linked to the invention.

The first results of the walls analyzed through calculation codes (finite element simulations) show a possible variation of the thermal transmittance of the proposed walls from 0.23 to 2.50 W/m<2>K.

The simplicity? of the technical solution makes success in terms of effectiveness probable even on real test walls, which will be the subject of future experimental tests.

In addition to the configurations described in Figures 2 (serpentine) and 4 (a round trip), any possible path of the pipes 1 in the walls P and between one wall and the other falls within the scope of the present invention.

As an example, in Figure 6 ? an example of a route (with continuous exchange) is shown, in which the pipe 1 alternates sections of flow in the internal wall PI with sections in the external wall PE.

In Figure 7 ? an example of a (spiral) path is shown, in which pipe 1, in each wall PI and PE, performs a spiral path from the periphery to the center and from the center to the periphery.

In Figure 8 ? reported a system in which the pipes 1 have a variable center distance; this configuration? particularly useful if you want to accentuate the heat exchange in particular areas of the walls P.

The pipes can be run in any layer of the adaptive wall, with decreasing efficiency the more the? the layers chosen are far from those immediately facing the internal and external environment.

Naturally, the principle of the invention remaining the same, the details of construction and the embodiments may vary widely with respect to what is described and illustrated purely by way of example, without thereby departing from the scope of the present invention.

Claims (20)

1) An adaptive wall (P) comprising, drowned inside the wall, a duct (1), in which said duct (1) develops more in the layer more? internal (SI) of the internal wall (PI) and in the layer pi? external (SE) of the external wall (PE) of the wall (P), in which inside said duct (1) is present a heat transfer fluid (2) which normally ? stationary in the rest condition, in which said fluid (2) ? free to move and circulate inside the duct (1) thanks to a thrust member (5), in which the thrust member (5) is? adapted to move said fluid (2) from its rest condition to make it flow inside said conduit (1), in which in said wall (P) a first internal surface temperature probe (Tpi) and a second probe ( Tpe) of external surface temperature, in which said first (Tpi) and second (Tpe) surface temperature probes are positioned embedded, respectively in the pi? internal (SI) of the internal wall (PI) and in the layer pi? (SE) of the external wall (PE) to measure the internal (Ta) and external (Tb) temperature, and in which said adaptive wall (P) also includes a control unit (4) which acquires the measured data (Ta, Tb) from said first (Tpi) and said second (Tpe) temperature probe, compares them and commands said thrust member (5) to leave said heat transfer fluid (2) stationary or flow depending on the result of this comparison between the internal temperature (Ta) and the external temperature (Tb). 2) The adaptive wall (P) according to claim 1, wherein the wall (P) is made of any material, and the two layers (SI, SE) where ? embedded the pipe that makes the duct (1) are made of high conductivity material? thermal. 3) The adaptive wall (P) according to claim 2, wherein said high conductivity material? thermal ? chosen from plasterboard, concrete and other building materials of similar conductivity? thermals. 4) The adaptive wall (P) according to one or more? of the preceding claims, wherein the wall (P) comprises an outer wall (PE), an intermediate wall (PM), wherein said intermediate wall (PM) comprises one or more? layers, and an inner wall (PI). 5) The adaptive wall (P) according to one or more? of the previous claims, wherein the internal temperature probe (Tpi) ? positioned in the center of the wall (P), away from thermal bridges and away from heat sources and ? drowned inside the inner wall (PI). 6) The adaptive wall (P) according to claim 5, wherein the external temperature probe (Tpe) ? positioned in the center of the wall (P), possibly in correspondence with the internal temperature probe (Tpi), away from thermal bridges and protected from rain and ? embedded inside the external wall (PE). 7) The adaptive wall (P) according to one or more? of the previous claims, wherein the pipes which form the duct (1) have a part of the trajectory which is in the vicinity of the external wall (PE) and a part of the trajectory which is in the vicinity of the inner wall (PI). 8) The adaptive wall (P) according to claim 7, wherein the pipes forming the conduit (1) have a serpentine trajectory or a round-trip development. 9) The adaptive wall (P) according to claim 7 or claim 8, wherein with a wall (P) divided into several? parts (A, B, C), each crossed by an independent duct trajectory (1), there is a thrust member (5) for each part (A, B, C,) of the wall (P). 10) The adaptive wall (P) according to claim 7 or claim 8, wherein with a wall (P) divided into several? parts (A, B, C), each crossed by an independent duct trajectory (1), a single thrust member (5a) and a DC manifold system are associated with the control of each trajectory on the valve V of the DC manifold . 11) The adaptive wall (P) according to one or more? of the previous claims, wherein the control unit (4) also works with mode? Proportional-Integral-Derivative type regulation which optimizes the on/off times of the pusher (5, 5a) according to the heat transfer in the desired direction. 12) The adaptive wall (P) according to one or more? of the preceding claims, in which the thrust member (5) is? chosen between a fixed number of revolutions pump, a three-speed pump, or a thrust element equipped with an inverter that allows you to vary it with continuity? the characteristic curve. 13) The adaptive wall (P) according to one or more? of the preceding claims, wherein the pipes forming the conduit (1) are made of a material selected from plastic, copper, iron. 14) The adaptive wall (P) according to one or more? of the preceding claims, wherein said heat transfer fluid (2) is chosen between pure water and water with added other substances. 15) The adaptive wall (P) according to claim 14, wherein said substances are additives, in particular glycol which inhibits freezing. 16) The adaptive wall (P) according to claim 15, wherein said additive ? with variable percentages between 10% and 40% depending on the climatic zone in which the device is installed. 17) The adaptive wall (P) according to one or more? of the preceding claims, wherein said temperature probes (Tpi, Tpe) are thermocouple probes, in particular T-type probes with constantan copper junction. 18) The adaptive wall (P) according to one or more? of the previous claims, in which the duct (1) has a continuous exchange path in which the pipe (1) alternates internal sections (1a) contained in the internal wall (PI) with external sections (1b) contained in the external wall (PE) , in which connecting sections (1c) are present between said internal sections (1a) and said external sections (1b). 19) The adaptive wall (P) according to one or more? of the previous claims, wherein the duct (1) has a spiral path from the periphery to the center and from the center to the periphery both in the internal wall (PI) and in the external wall (PE). 20) Method of operation of an adaptive wall (P) according to any one of the preceding claims, wherein said method comprises the steps of: - measure in one step (10) the internal temperature (Ta) and the external temperature (Tb) using the temperature probes (3, Tpi, Tpe), - read in one step (20) the temperatures (Ta, Tb) measured by the temperature probes (3, Tpi, Tpe) via a control unit (4), - in the case of winter, using the control unit (4), compare in a decision step (30) the two temperatures (Ta, Tb) measured by the probes (Tpi, Tpe), - in one step (35) if the external temperature (Tb) measured by the probe (Tpe) ? lower than or equal to the internal temperature (Ta) measured by the probe (Tpi), keep the movement pump off (5), or alternatively - in one step (40) if the external temperature (Tb) measured by the probe (Tpe) ? greater than the internal temperature (Ta) measured by the probe (Tpi), turn on the movement pump (5) to make the fluid (2) flow inside the duct (1), - at the end of step (35) or step (40) the control returns to step (20), - in the case of summer, using the control unit (4), compare in a decision step (50) the two temperatures (Ta, Tb) measured by the probes (Tpi, Tpe), - in one step (55) if the external temperature (Tb) measured by the probe (Tpe) ? lower than the internal temperature (Ta) measured by the probe (Tpi), turn on the movement pump (5) to make the fluid (2) flow inside the duct (1), or alternatively - in one step (60) if the external temperature (Tb) measured by the probe (Tpe) ? greater than or equal to the internal temperature (Ta) measured by the probe (Tpi), keep the movement pump off (5), - at the end of step (55) or step (60) the control returns to step (20).