WO2012032422A1

WO2012032422A1 - Decentralized recuperator

Info

Publication number: WO2012032422A1
Application number: PCT/IB2011/052542
Authority: WO
Inventors: Virginijus Rutkauskas
Original assignee: Virginijus Rutkauskas
Priority date: 2010-09-06
Filing date: 2011-06-10
Publication date: 2012-03-15
Also published as: LT2010064A; EP2614313A1; LT5829B

Abstract

The object of this invention is a special design of counter-flow exchange recuperator, which is easily integrated into the partition, and lengthening of its dimensions longitudinally does not increase transverse dimensions. This guarantees not only easy mounting and compactness, but also ensures very good heat exchange in heat exchanger of recuperator. The basis of heat exchanger is made of a corresponding system, which can be rotated around its longitudinal axis and in this way operate in not only ventilation mode, but also in ventilation and cooling mode. Recuperator system has holes, where material is placed, ensuring not only heat exchange, but also moisture transfer. After the corresponding accordion-shaped endings are cut off in the design of heat exchanger, moisture and / or heat permeable fibres are inserted between loosely hanging plates. These fibres do not let air or hardly let air, reduce system vibration and improve general system moisture permeability. To reduce electricity consumption, surrounding surfaces of the protective elements, which protect airstreams, are covered with photocell layer that converts solar energy to electrical energy.

Description

DECENTRALIZED RECUPERATOR

Technical Field

This invention pertains to a field of ventilation equipment, especially decentralized recuperators and heat exchangers, designed for ventilation of premises and retaining / maintaining of heat.

Background Art

The issue of ventilation of premises has been relevant even in the old days, however, now, when people living in cities spend approximately 80% of their time indoors, this issue becomes especially important. Excluding the issue of ventilation of premises, there is another relevant issue: together with the air outlet from the premises, heat and moisture come out as well. Therefore, people make efforts to design various types of devices, which could ensure not only good ventilation, but also save heat and maintain moisture. Over time, as new needs and requirements arise, novel recuperators were designed having new features and exclusive designs.

There is a known Russian patent No. RU2328683, published on July 10^th of 2008. This patent describes the passive ring-shaped plate multidirectional recuperator, where the incoming airstreams, going through in parallel arranged metal plates, which make a ring-shaped design, transfer their heat to the plates and are indrawn into the premises or extruded from the premises. The advantage of this design is that few airstreams of different directions can inflow into this design, however, this ring-shaped design significantly restricts the path length of the airstreams going through the design. Due to this reason, few issues are typical to this type design: this system does not ensure good heat exchange between the incoming and outgoing airstreams; moreover, the mounting process of this design is complicated, because the whole system has to be fully mounted to the wall.

There are known another, Korean patent No. KR20040059267 (EP1621824), published on February 1^st of 2006. This patent presents the ventilation system, which, when using ventilators, extrudes the air of the premises to the outside, and draws specially prepared air into the premises. In this system, the air supplied from the outside goes through specially prepared medium, where the outside air is suitably prepared: heated, moistened and etc. For this aim, water supply system is provided in the equipment. However, this solution is not economical, because the incoming and outgoing airstreams go through separate channels and there is no heat exchange between them, i.e. the heat of the air in the premises is extruded to the outside and is not recovered. Furthermore, this equipment is very complicated in respect of its mounting and control, because control of the water supply system is added to control of the ventilation system.

There is one more known, Chinese patent No. CN201269705 , published on July 8^th of 2009. This patent describes the tube-type heat exchanger. Air for the premises is supplied via the tubes, and heat is abstracted from the tubes, inserted in the separate closed area, by using a complex tunnel system. This design is quite cumbersome, since it requires a complex heat abstraction system. The tubes are long and have small diameter, therefore strong resistance to airstream occurs inside them. Moreover, tubes of this type can easily be blocked with fat or other undesirable objects of small sizes.

The closest patent according to the prior art is the Swiss patent No. CH699308, published on February 26^th of 2010. This patent describes the cross-exchange heat exchanger design, which is integrated to a wall and designed for ventilation of the premises. The system is comprised of the area, where heat exchange of the airstreams is performed, ventilators and electronic control area. Despite the fact that the whole system is quite mobile and does not require additional heat abstraction system, it has a few drawbacks. One of those drawbacks is difficult assembly works, because in the cross-exchange heat exchanger, the incoming and outgoing airstreams are arranged at a 90⁰ angle, and, when increasing the air path length, all overall dimensions of the device must increase, while higher dimensions significantly increase the prime cost of the device. The other drawback is that the maximum theoretic heat transfer efficiency of the cross-exchange recuperator reaches only 50%. Furthermore, this analogue design does not include cooling (bypass circuit) mode.

Technical Problem

The goal of the present invention is a special counter flow-heat exchange recuperator, which is easily integrated into the partition (for example, wall) and the increase of its dimensions in longitudinal direction does not influence the increase of transverse dimensions, i.e. recuperator can be long and have small diameter. This guarantees not only easy mounting and compactness, but also ensures very good heat exchange in the heat exchanger of the recuperator, the theoretical efficiency of which can reach η=1. The heat exchanger, mounted inside the recuperator, which can be long and have small diameter, is inserted into a round tube-shaped design, having tight or tightly screwed endings with specially formed corresponding holes on the side for warm / cold airstream outlet / inlet.

The main feature of this invention is that:

this counter flow-heat exchange recuperator can be sufficiently long and have narrow diameter, which ensures good heat exchange;

heat exchanger, when using the mode switch, can be rotated around its longitudinal axis and in this way acts not only in ventilation mode, but also in ventilation and cooling (heat abstraction) (bypass) mode;

recuperator system has special holes into which material can be placed, ensuring not only heat exchange, but also moisture transfer from warm airstream to cold airstream;

heat exchanger design can have moisture and / or heat permeable fibres, which do not let or hardly let air, reduce system vibration and improve overall system moisture permeability;

there are corresponding ventilators for airstreams direction;

accumulators are placed into the recuperator system for accumulation of electrical energy and its supply;

there are filters for cleaning directed airstream from rubbish, undesirable objects of small dimensions and unpleasant smell; and

there is a suitably mounted electronic control equipment, which can have transducers of temperature, pressure, moisture and other parameters, as well as control ventilators and other related auxiliary electronic equipment.

Technical Solution

Advantageous Effects

Description of Drawings

Fig. 1 shows a principal scheme of the counter-exchange recuperator design (side view).

Fig. 2 shows a principal scheme of the counter flow-exchange recuperator design in a cross-section (in ventilation and cooling modes).

Fig. 3 shows a principal scheme of the counter-exchange recuperator design in a cross-section (in ventilation mode).

Fig. 4 shows an overall view of the counter-exchange recuperator design (additional illustrating drawing).

Best Mode

Two types of recuperators are normally used worldwide: cross-flow or counter flow-heat exchange recuperators. Cross-flow heat exchange recuperators are most common, however, this type of design has a few drawbacks. One of these drawbacks is related to assembling: when mounting cross-flow recuperators, two additional holes have to be drilled in the partition (for example, wall): for warm and cold air. This makes mounting very difficult and increases linear heat losses (which are accumulating in the places of fixation) of the ventilation system. Moreover, in case of cross-flow recuperator, when aiming to lengthen the paths of warm and cold airstreams, the longer the path of the airstream is, the longer (longer period of time) takes the heat exchange in the recuperator, it is necessary to increase the transverse dimensions of the recuperator, which is usually not reasonable. On the other hand, theoretic efficiency of heat transfer of the cross-flow recuperator reaches only η=0.5, while theoretic efficiency of heat transfer of the counter-exchange recuperator can reach even up to η=1.0. However, counter-exchange recuperators are normally implemented as a tube system or ring-shaped plate system. The tube system has sufficiently high impedance, can be easily blocked, is difficult to clean and requires additional heat abstraction equipment. The ring-shaped plate system is similar to cross-flow recuperator (for example, RU2328683) and has alike drawbacks: difficult mounting due to big dimensions and too low efficiency of heat abstraction due to insufficiently long path in heat exchanger.

To achieve the highest possible efficiency η of heat transfer and to avoid recuperator mounting difficulties, basically new design of counter-exchange recuperators is provided, the overall scheme of which is presented in Fig.1. This recuperator (1) consists of these main structural components: cold part of recuperator (2), warm part of recuperator (3), partition design (4) and special heat exchanger (5) design, placed inside recuperator (1). Ideally, the mentioned cold (2) and warm (3) parts of recuperator are tube-shaped, the length of which, when the diameter of recuperator (1) is not changed, can be long enough and can be changed depending on the need. To ensure compactness of the design, recuperator (1) is integrated into the partition (4), the function of which can be performed by the internal / external wall of the ventilated building or premises. This way, in respect of the partition (4), cold part of recuperator (2) is directed to the outside, while warm part of recuperator (3) - into the premises. The heat exchanger (5) design itself is placed into a round tube (2, 3), cold (6) and warm (7) endings of which are tightly closed or tightly screwed. To ensure the functions of ventilation and heat exchange, the mentioned recuperator (1) has four special vents (8, 9, 10, 11). Warm part (3) of recuperator has two vents arranged one in front of another (8, 10): one vent (8) is for the premises air inlet into the heat exchanger (5), the other vent (10) is for the outside air outlet from the heat exchanger (5) into the premises. Cold part (2) of recuperator also has vents (9, 11) arranged one in front of another: one vent (9) is for the premises air outlet from the heat exchanger (5) to the outside, and the other vent (11) is for the outside air inlet into the heat exchanger (5). The area of the mentioned vents (8, 9, 10, 11) can differ, i.e. height and width can be changed depending on the need. Ventilator is mounted close to the vent (8), extruding or drawing the premises air to the heat exchanger (5), ventilator is mounted close to the vent (11), extruding the outside air to the heat exchanger (5). Moreover, if necessary, to avoid additional reduction of heat exchanger permeability resistance, two more ventilators can be connected and put into operation close to the vents (9, 10). Furthermore, to ensure cleanliness and to protect heat exchanger (5) from undesirable small objects or rubbish, specially selected air filters are mounted in front of ventilators. The mentioned recuperator (1) can also have mode switch (12), which can rotate and change the arrangement of the heat exchanger (5) in the recuperator (1) in respect of the mentioned switch (12) rotation axis. The mentioned mode switch (12) can be rotated by hand or specially adjusted electronic and / or mechanical gearwheel or mechanism of similar purpose. All mentioned parts (2, 3, 5, 6, 7, 12) of recuperator (1) are made of suitable firm heat and water resistant materials, for example, metal, glass, ceramics, hard plastic or composite materials. Dimensions of all mentioned parts can be recorded and recalculated and adjusted for every separate installation case.

Fig. 2 provides a cross-sectional view of counter-exchange recuperator (1) design. Heat exchanger (5) integrated into recuperator (1) is closely linked with the mode switch (12), which can rotate the heat exchanger (5) of the recuperator (1) longitudinally around the axis of the mentioned switch (12). One of the ways of implementation provides heat exchanger (5), the basis is which is made of heat exchanger plates (13) arranged in parallel to one another, along which incoming and outgoing airstreams flow from different sides in opposite directions. Depending on the design of recuperator (1), the distance between heat exchanger plates (13) can be fixed, equal, different or adjusted. Heat exchanger plates (13) can be made of good heat conducting stainless material, for example, metal, glass, ceramics, carbon, plastic, special heat and water resistant paper, composite materials and etc. For the incoming and outgoing airstreams not to mix, heat exchanger plates (13) are connected based on 'accordion principle' so that on the sides of those plates cone-shaped joints are formed, not allowing airstreams to mix. The mentioned cone-shaped joints can be more or less sharp and can have rectangular or other irregular form. Every plate (13) of the heat exchanger meets different airstreams, i.e. from one side of the plate the air extracted from the premises is transferred, while from the opposite side of the plate the air indrawn into the premises is transferred. Heat exchanger plates (13) conduct heat well; therefore warm air outlet from the premises transfers its heat to heat exchanger plates (13), and these plates transfer collected heat to cold outside airstream flowing from the other side. In this way, the premises are ventilated and the heat is also preserved and maintained. The mentioned plates (13) can have different shapes: flat, rough (sponge type) and etc.

Since heat exchanger (5) design is square or rectangular, after mounting it into round tube (cylinder) (2, 3), four arc-shaped cavities are formed in the inner perimeter of the mentioned tube. To direct air only to heat exchanger (5), two opposite cavities can be sealed with material (14), and the rest two - not sealed, i.e. left free. This material (14), presented in Fig. 3, performs not only sealing function, but also reduces vibration in heat exchanger (5); moreover, which is very important, it transmits moisture of the premises air, which passes to the outside airstream and together with this stream it is transferred to the premises again. In this way, air outgoing from the premises leaves not only part of its heat in the heat exchanger (5), but also part of its moisture. To minimize system vibration and maximize moisture transfer in the heat exchanger (5), the mentioned cone-shaped joints or joints of other shape, present between the plates (13), are cut off, and between loosely hanging plates, close to their endings, along the heat exchanger (5), (soft) moisture and / or heat permeable fibres are hermetically attached, which do not let air or hardly let air.

Heat exchanger (5) is not stationary fixed in the tube (2, 3), therefore, when using mode switch (12) and rotating heat exchanger (5) around its longitudinal axis, recuperator (1) can work in a few modes: ventilation and cooling (by pass heat abstraction) mode (Fig. 2) and ventilation mode (Fig. 3). Ventilation mode involves premises air extrusion to the outside, outside air supply to the premises, heat and moisture exchange in the heat exchanger (5). Ventilation and cooling mode includes premises air extrusion to the outside, outside air supply to the premises, heat abstraction to the outside and moisture exchange in heat exchanger (5). Device (1) merges premises air with outside air, therefore, no additional pipe fitting is needed.

Due to direct air flow into heat exchanger, air supply path is shortened and pressure losses are reduced. This results in lower electricity costs. Recuperator (1) of this type is very compact and is easily mounted onto the wall of the building, because during the mounting it is only necessary to drill one hole in the wall, diameter of which is very close to the transverse diameter of recuperator (1). Since there is only one hole, linear heat losses in the perimeter of the system reduce.

With the aim to electronically control provided recuperator (1) system, corresponding control equipment is installed in the system and close to it, which can have temperature, pressure, moisture and other parameters sensors as well as control ventilators and other related auxiliary electronic devices.

To reduce electricity consumption, surfaces of the surrounding protective elements, protecting the mentioned airstream waves (8, 9, 10, 11), are covered with photocell layer, which converts solar energy into electric energy. Moreover, accumulators are integrated inside recuperator (1), designed for electric energy collection and supply to recuperator (1) parts / blocks depending on the need.

Heat exchanger (5) of recuperator (1) can be made of electrically conductive material and, when conducting electric current, it can be warmed / heated. In this way, it is possible not only to cool, but also to heat the air that is inlet into the premises. Furthermore, when heating heat exchanger (5), it is possible to defrost and evaporate the condensate, which is collected in heat exchanger (5) during the usage of recuperator (1).

Design of the provided recuperator (1) reaches very high technical characteristics, is easy and cheap to manufacture, compact during mounting and exploitation in ventilation, ventilation and cooling as well as air warming modes.

If luminous element is integrated into one surface of the ending of recuperator (1), which is seen from the outside, then, when using the combination of these recuperators, it is possible to illuminate the walls of the building and, depending on the direction of luminous elements, surroundings of the building.

Mode for Invention

Industrial Applicability

Sequence List Text

Claims

1. Decentralized recuperator, comprising of heat exchanger, ventilators and / or electronic control unit, c h a r a c t e r i z e d in that it consists of:

warm recuperator part (3), placed in the premises in respect of partition design (4);

cold recuperator part (2), placed on the outside in respect of partition design (4);

cold (6) and warm (7) endings, designed for sealing the mentioned parts (2, 3) of recuperator;

holes designed for airstreams flow (8, 9, 10, 11);

square or rectangular heat exchanger (5), integrated into the mentioned parts of recuperator (2, 3);

material (14), performing the functions of sealing, vibration reduction and moisture transfer;

ventilators, designed for airstreams direction;

filters, designed for airstreams cleaning; and

electronic control unit,

which can have temperature, pressure, moisture and other parameters sensors / transducers

and control the mentioned ventilators and other related auxiliary electronic devices;

where

the mentioned cold (2) and warm (3) parts of recuperator are tube-shaped, the length of which, when the diameter of recuperator (1) does not change, can be sufficiently long and adjustable depending on the need;

cold (6) and warm (7) endings are tightly closed or screwed;

there are two vents (8, 10), arranged one in front of another, in the warm part (3) of recuperator, where one vent (8) is for the premises air inlet to heat exchanger (5), while the other vent (10) is for the outside air outlet from heat exchanger (5) to the premises;

there are also two vents (9, 11), arranged one in front of another, in the cold part (2) of recuperator, where one vent (9) is for premises air outlet from heat exchanger (5) to the outside, while the other vent (11) is for outside air inlet to heat exchanger (5);

in the ventilation mode, heat exchanger (5) performs ventilation, heat transfer and moisture transfer functions, while in the ventilation and cooling mode, it performs ventilation, cooling (heat abstraction) and moisture transfer functions.

2. Decentralized recuperator according to claim 1, c h a r a c t e r i z e d in that the basis of the mentioned square or rectangular heat exchanger (5), integrated into the mentioned recuperator parts (2, 3), is made of in parallel arranged heat exchanger plates (13), along which airstreams flow from different sides in opposite directions,

where

heat exchanger plates (13) are connected in 'accordion principle' so that cone-shaped joints are made on the sides of the heat exchanger (5), not allowing the airstreams that flow along the plates to mix;

the mentioned cone-shaped joints can be more or less sharp, as well as these mentioned cone-shaped joints can be rectangular or have other incorrect form.

3. Decentralized recuperator according to any of the preceding claims 1-2, c h a r a c t e r i z e d in that ventilator, extruding or drawing air from the premises to heat exchanger (5), is mounted close to the vent (8), and ventilator, extruding or drawing air from the outside to heat exchanger (5), is mounted close to the vent (11); in order to additionally reduce permeability resistance of heat exchanger, two more corresponding ventilators are connected and put into operation close to the vents (9, 10).

4. Decentralized recuperator according to any of the preceding claims 1-3, c h a r a c t e r i z e d in that it additionally has a special mode switch (12), which, aiming to switch recuperator (1) from ventilation and cooling mode to ventilation mode or vice versa, can rotate and change the arrangement of heat exchanger (5) in recuperator (1) in respect of the rotational axis of the mentioned switch (12), where the mentioned mode switch (12) can be rotated by hand or by specially adjusted electronic and / or mechanical gearwheel or mechanism of similar type.

5. Decentralized recuperator according to any of the preceding claims 1-4, c h a r a c t e r i z e d in that all mentioned parts of recuperator (1) and heat exchanger are made of the same or different hard and heat and water resistant materials, for example, metal, glass, carbon, ceramics, hard plastic, special paper, composite materials.

6. Decentralized recuperator according to any of the preceding claims 1-5, c h a r a c t e r i z e d in that aiming to minimize system vibration and maximize moisture transfer in heat exchanger (5), the mentioned cone-shaped joints or joints of other irregular shape, present between the plates (13), are cut off, and between loosely hanging plates, close to their endings, moisture and / or heat permeable fibres are hermetically placed, which do not let air or hardly let air.

7. Decentralized recuperator according to any of the preceding claims 1-6, characterized in that aiming to reduce electrical energy consumption, surrounding surfaces of the protective elements, which protects the mentioned airstreams (8, 9, 10, 11), are covered with photocell layer, which converts solar energy to electrical energy, which can be collected in accumulators, integrated inside recuperator (1).

8. Decentralized recuperator according to any of the preceding claims 1-7, c h a r a c t e r i z e d in that aiming to heat the air, coming from the outside to the premises, as well as defrost and evaporate the condensate, which is collected in the heat exchanger (5) during the usage of recuperator (1), heat exchanger (5) of recuperator (1) is made of electrically conductive material and, when conducting electric current, it can be warmed / heated.

9. Decentralized recuperator according to any of the preceding claims 1-8, c h a r a c t e r i z e d in that a luminous element is integrated into the surface, seen from the outside, of one ending of recuperator (1), which can illuminate walls of the building and / or surroundings of the building.