Decentralized heat recovery air handling unit

Abstract

This decentralized heat recovery air handling unit (19) comprises an indoor module (16), a recessed module (17), and an outdoor module (18), said modules (16, 17, 18) being compactly connected to one another, said recessed module (17) being intended for installation in an exterior wall of a building and comprising a corrugated heat exchanger (5). The heat exchanger (5) comprises several U-shaped cross-sectional heat exchange air ducts arranged equidistant from one another and forming a continuous corrugated space of heat exchange segments, separators (2) with an aerodynamic profile being arranged at the ends of the exchanger (5), a fan (8) being arranged on each distal surface of the separators (2) relative to the exchanger (5), the fans (8) being arranged non-coaxially to one another. Figure for the abbreviation: Figure 4

Description

Title of the invention: Decentralized air treatment unit with heat recovery Technical field

[0001] The invention relates to the field of ventilation, in particular the ventilation of residential and non-residential (commercial) premises. The invention relates more particularly to decentralized air treatment units with heat recovery and can be used to transfer heat and energy from a flow of stale air extracted from a room to a flow of fresh air drawn from outside the room and intended to replace the stale air in this room. Previous techniques

[0002] Many technical solutions of various shapes and designs for natural ventilation of residential and non-residential premises are known.

[0003] The search for optimal ventilation solutions is motivated by the desire to construct rooms in such a way as to ensure maximum energy savings in the building. However, an increase in the energy saving coefficient of the building leads to a proportional decrease in the self-regulation of the indoor climate.

[0004] In other words, due to the use of central heating, the operation of a large number of household appliances and other modern technological factors, these premises are subject to significant dehumidification and air pollution inside the premises, thus creating favorable conditions for the occurrence of allergic diseases and respiratory pathologies.

[0005] In spring and summer, energy-efficient buildings do not vent high humidity well, making it difficult for natural air circulation inside the building, creating favorable conditions for the development of harmful fungi and microorganisms.

[0006] The above statements have been known to mankind for a long time. Therefore, in many developed countries, medical institutions recommend frequent ventilation.

[0007] In most countries, regulations are in place to govern the standards for permanent air exchange systems.

[0008] Ventilation is mainly carried out by opening windows, thus ensuring natural circulation of air inside the room. However, ventilation by opening windows alone creates many inconveniences. In particular, in winter, an open window, due to its large surface area, cools considerably the room, and in summer it heats it up, which leads to significant energy consumption to ensure acceptable and comfortable working and living conditions. This is why the creation of ventilation systems takes a lot of time.

[0009] Document UA 148 372 - U describes a decentralized heat recovery air treatment system, which comprises a heat exchanger of a heat recovery ventilation system having the shape of a cylinder with several heat exchange segments and two covers, and the plurality of heat exchange segments are arranged radially and converge at the base, forming a transverse circular hole in the center, where each heat exchange segment has the shape of an elongated V-shaped plate, and the heat exchange segments are arranged equidistantly and with a certain offset, forming a continuous corrugated space of the heat exchange segments of the cylinder, each of the covers is equipped with an outer guide ring and an inner ring of smaller diameter, between which are located, spaced apart by a certain interval corresponding to the size of the space between the heat exchange segments adjacent to the covers,the outer and inner distribution holes of the front and rear covers, respectively, the holes are arranged in a checkerboard pattern relative to the smaller diameter inner ring, and the checkerboard order of the front and rear covers of the outer and inner distribution holes is offset by one step.

[0010] Document UA 146 223 - U describes a decentralized air treatment system with heat recovery and is considered to be the closest state of the art. This system contains a recuperator with air ducts, a fan and a heat exchanger interconnected and mounted in the wall of the room, between its outer and inner surfaces, and two concentric cylinders with a straight passage are installed in the opening between the outer and inner surfaces of the room, between which is fixed, on the outer surface of the inner cylinder, a reinforced corrugated heat exchanger Q-shaped in cross-section and, on the inner surface of the cylinder, an external and internal fan are installed oppositely, the openings of the system being equipped with corresponding external and internal covers,where the inner cover is respectively equipped with an air supply grille and an internal air leakage slot with an air diffuser, the outer cover is further equipped with a condensate discharge opening extending beyond the surface of the outer wall, an air receiving grille and a corresponding internal air outlet grille.

[0011] The disadvantages of the closest state-of-the-art system are as follows: inadequate technical specifications; • imperfect design of the recuperator, because when air passes along the heat exchange surface of the corrugated heat exchanger, the existing cutouts in the hollows of the heat exchanger reduce the heat exchange surface; • air flows are not balanced; • the power supply unit is located in the room module and, therefore, does not provide additional heating of the recuperator; • the design of the recuperator creates excessive condensation and leads to a risk of icing; • the ventilation hood with external grille is of the open type, which does not protect the exhaust duct from the wind. Statement of the invention

[0012] The objective of the invention is to create a decentralized air treatment unit with heat recovery which overcomes the drawbacks of the prior art.

[0013] The invention relates to a decentralized heat recovery air treatment unit comprising a room module, a built-in module and an outdoor module, said modules being connected to each other in a compact manner. The built-in module is intended to be installed in an external wall of a building and comprises a corrugated heat exchanger. The heat exchanger comprises several heat exchange air ducts, of U-shaped cross-section, arranged equidistant from each other and forming a continuous corrugated space of heat exchange segments, separators with an aerodynamic profile being arranged at the ends of the exchanger, a fan being arranged on each distal surface of the separators with respect to the exchanger, the fans being arranged non-coaxial to each other.

[0014] Such a unit has several advantages: • thanks to the corrugated heat exchanger placed in the module embedded in the wall with a plurality of equidistantly located heat exchange air ducts, forming a continuous corrugated space of heat exchange segments of the cylinder, the heat exchanger has a U-shaped cross-section and is not straight, but corrugated along its entire length, which allows increasing the heat exchange surface and transforming the laminar air flow into turbulent flow, while improving the transfer of thermal energy by mixing the air in the cells of the heat exchanger, which leads to an increase in the heat exchange efficiency between the incoming and outgoing air; • air flow resistance is reduced by placing aerodynamically profiled plastic separators on both sides of the heat exchanger in the wall-mounted module; • the amount of condensation is reduced, as well as the risk of frost inside the product and the appearance of ice accumulation on the street side; the reduction in the amount of condensation minimizes the formation of ice on the surface of the recuperator, which leaves the high efficiency and aerodynamic properties of the recuperator unchanged, and improves the performance of the product as a whole;

[0015] Preferably, the ambient module comprises a housing provided with an electronic screen for visual monitoring of the operation of the unit, the housing comprising at least one valve for blocking an air flow.

[0016] Advantageously, the housing comprises in its middle an inclined partition so as to change the direction of the supply and exhaust air flows passing through a wall air duct of the heat exchanger. Such a configuration makes it possible to improve the circulation of the air flows.

[0017] According to one characteristic, the partition is provided with an air purification filter.

[0018] For example, the unit includes a noise absorber installed on the housing of the room module.

[0019] Preferably, the outdoor module is provided with an external ventilation cover with a grille, the cover being provided with an inclined portion so as to protect the unit from winds perpendicular to the exterior wall.

[0020] According to another characteristic, the separators comprise external and internal distribution openings offset by a checkerboard pitch.

[0021] For example, the unit includes a chassis for a distribution / switching card configured to allow resizing of the unit.

[0022] For example, the unit includes heating elements installed near the heat exchanger. Brief description of the drawings

[0023] Other aims, characteristics and advantages of the invention will appear on reading the following description, given solely by way of non-limiting example, and made with reference to the appended drawings in which:

[0024] [Fig-1] is a perspective view of a decentralized heat recovery air treatment unit according to the invention;

[0025] [Fig.2] is a perspective view of a room module of the unit of [Fig.l];

[0026] [Fig.3] is a front view of the ambient module of [Fig.2];

[0027] [Fig.4] a sectional view along axis IV-IV of [Fig.l];

[0028] [Fig.5] a sectional view along the VV axis of [Fig.l];

[0029] [Fig.6] is a side view of a built-in module of the unit of [Fig.l];

[0030] [Fig.7] is a front view of the embedded module of the module of [Fig.6]; and

[0031] [Fig.8] is a sectional view along axis VIII-VIII of [Fig.7]. Detailed description of at least one embodiment

[0032] A decentralized heat recovery air treatment unit according to the invention is described with reference to Figures 1 to 8.

[0033] The unit 19 may comprise three modules: an ambient module 16, a recessed module 17 for example in a wall and an external module 18. The modules 16, 17 and 18 are connected to each other in a compact manner and form a single structure.

[0034] The room module 16 consists of a housing 12 with flaps 9 on the right and left sides to block the air flow. On the one hand, the stale air from the room is extracted to be discharged outside, and on the other hand, fresh air, heated or cooled (depending on the season) is injected. In the middle of the housing there is an inclined partition 11 which serves as a separator and guide for the supply and exhaust air flows which pass through the embedded coaxial duct of a heat exchanger 5 to the right and left sides of the housing 12 of the room module 16. Preferably, the partition 11 is provided with an air purification filter 10. An electronic display 13 is installed at the bottom of the housing and displays certain information on the operating mode and the air parameters (time, temperature and humidity of the incoming and outgoing air, flow rate, air quality and other information).The arrangement of the control elements of a card 4 in the housing 12 and the inclination of the screen 13 allow better visual control of the product while improving performance. The chassis 6 of the distribution / communication board is designed to allow dimensional modifications. The front part of the housing 12 comprises a main panel 14 and a screen panel 15. Preferably, the screen panel 15 is made of a translucent material through which the information of the screen 13 is visible. Preferably, a sound absorber for example made of polymer (not shown) is placed on the housing 12 of the room module 16 so as to help reduce the noise generated by the air flow and also to reduce the risk of condensation caused by the temperature difference between the air and the air entering the room.

[0035] The built-in module 17 comprises a corrugated metal heat exchanger 5 or counter-flow recuperator, on both sides of which are installed plastic separators 2 with an aerodynamic profile in order to reduce the resistance to the air flow. The built-in module 17 also comprises two axial fans 8 located oppositely, but not coaxially, on one side and the other of the heat exchanger 5, behind the separators 2. The heat exchanger 5 has a U-shaped cross-section and is not straight, but corrugated or with other geometric shapes similar along its length, so as to increase the heat exchange surface area and transform a laminar air flow into a turbulent flow 20, thereby improving the transfer of thermal energy by mixing the air in the heat exchanger cells. These two factors generally lead to an increase in the efficiency of the heat exchange between the incoming and outgoing air. The plastic separators 2 having an aerodynamic profile to reduce the airflow resistance ensure a smooth entry and exit of air to the heat exchanger 5, which reduces the aerodynamic resistance of the unit 19 as a whole and has a positive effect on reducing aerodynamic noise and energy consumption. The plastic separators 2 significantly reduce the amount of condensation, which decreases the risk of icing inside the product and the occurrence of ice accumulation outside.Furthermore, the material of the separators 2, by reducing the amount of condensate, minimizes the formation of ice on the surface of the recuperator, which leaves the high efficiency and aerodynamic properties of the recuperator unchanged, thus improving the performance of the unit 19 as a whole. Inside the heat exchanger 5 there is a power supply (not shown) and a controller of the unit (not shown). The heat inevitably generated by the power supply and by the controller is not lost, but is used to heat the heat exchanger 5 and then the incoming air. Air monitoring sensor boards (temperature, humidity, CO2) are installed on both sides of the heat exchanger 5 (not shown).All board connections are made using connectors, without the need for bulky terminal blocks or cumbersome cables, which increases the reliability of connections and saves internal space for unhindered airflow. The axial fans 8 are equipped with specially profiled rotating blades (not shown), which are less noisy than conventional rotating blades and provide a balanced air flow. Preferably, heating elements 7, 21 are installed near the heat exchanger 5, so as to provide protection against icing and possible condensation, and to provide additional heating of the air when outside temperatures are low.

[0036] A ventilation hood with an external grille 18 protects the unit 19 from atmospheric precipitation and solid elements coming from the street (leaves, birds, insects and other debris). The hood 18 is designed to protect the unit 19 from the perpendicular direction of the wind, relative to the wall of the building (not shown). The bottom of the hood 18 has an orifice for discharging condensation (not shown) which may form in the unit under certain conditions.

Claims

Claims

1. Decentralized heat recovery air treatment unit (19) comprising a room module (16), a built-in module (17) and an outdoor module (18), said modules (16, 17, 18) being connected to each other, said built-in module (17) being intended to be installed in an external wall of a building and comprising a corrugated heat exchanger (5), said unit (19) being characterized in that said heat exchanger (5) comprises several heat exchange air ducts, of U-shaped cross-section, arranged equidistant from each other and forming a continuous corrugated space of heat exchange segments, separators (2) with an aerodynamic profile being arranged at the ends of the exchanger (5), a fan (8) being arranged on each distal surface of the separators (2) with respect to the exchanger (5), the fans (8) being arranged non-coaxial to each other to the other.

2. Unit (19) according to claim 1, wherein the ambient module (16) comprises a housing (12) provided with an electronic screen (13) for visual monitoring of the operation of the unit, the housing (12) comprising at least one valve (9) for blocking an air flow.

3. Unit (19) according to claim 2, in which the housing (12) comprises in its middle a partition (11) inclined so as to change the direction of the supply and exhaust air flows passing through a wall air duct of the heat exchanger (5).

4. Unit (19) according to claim 3, wherein the partition (11) is provided with an air purification filter (10).

5. Unit (19) according to any one of the preceding claims, comprising a noise absorber installed on the housing (12) of the ambient module (16).

6. Unit (19) according to any one of the preceding claims, in which the external module (18) is provided with an external ventilation cover with grille, the cover being provided with an inclined part so as to protect the unit (19) from winds perpendicular to the external wall.

7. A unit (19) according to any preceding claim, wherein the dividers (2) comprise outer and inner dispensing openings offset by a checkerboard pattern.

8. A unit (19) according to any preceding claim, comprising a chassis for a distribution / switching card (4) configured to allow resizing of the unit.

9. Unit (19) according to any one of the preceding claims, comprising heating elements (7, 21) installed near the heat exchanger (5).

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