GB2164135A

GB2164135A - Regenerative air conditioning unit

Info

Publication number: GB2164135A
Application number: GB08417236A
Authority: GB
Inventors: Waldemar Hryniszak
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-07-06
Filing date: 1984-07-06
Publication date: 1986-03-12
Also published as: GB8417236D0; GB2164135B

Abstract

A heating and ventilating unit consists of a regenerative heat exchanger whereby its heat exchanger part, i.e. the matrix being contained in a rotating disc 1, is preferably made from a ceramic engineering material. This matrix is sub-divided into at least two circular sectors 2,3 each of which fulfils a different heat exchanging function. Furthermore, a combustion chamber 4, two blowers 5,6, one for the fresh air the other for the stale air as well as means for driving the disc and controlling the performance of the unit are included. A cooling capability is achieved by expanding the stale air in an expander (turbine) 10 thus reducing its temperature before passing through the matrix of the heat exchanger and raising the pressure of this stale air after leaving the matrix in a compressor before being expelled to the atmosphere. <IMAGE>

Description

SPECIFICATION A regenerative air conditioning unit with waste heat recovery As the envelope of a building is made tighter thus reducing heat losses through the fabric as well as due to uncontrolled ventilation, controlled ventilation, i.e. a continuous replacement of stale air by fresh air becomes essential, otherwise not only condensation but also hazards to health can occur. In other words, "tighter" walls, doors and windows require a controlled ventilation.

Increasingly not only heating in winter but cooling in supper is the prerequisite of a healthy environment in the rooms of a building. The increased use of electronic devices for all sorts of purposes increase the heat generated and the need to cool.

In accordance with the invention, a cooling capability is added to a heating and ventilating unit as described in detail in patent application No. 8227321.

Such a unit consists (see Fig. 1) of a regenerative heat exchanger, its heat exchanging part, the matrix, is contained in a rotating disc (1) made from a ceramic engineering material.

This matrix in turn consists of a multitude of small flow channels surrounded by thin walls.

Two circular sectors, a peripheral (2) and a central (3) are foreseen fulfilling different heat exchanging functions. Furthermore, there is a combustion chamber (4) as well as two preferably single stage radial compressors (blowers) (5) and (6) driven by electric motors (7) and (8) respectively, together with the auxiliaries for driving the disc, for injecting and controlling the fuel for ignition and its control and so on. Instead of two circular sectors three can be arranged in such a way that the colder air flows through the inner and outer sectors and the hotter through the central sector.

The operation of such a heating and ventilating unit is such that the by far largest portion (80-90%) of the fresh air (FA) passes through what could be called the airpreheating sector (2) and the rest 10-20% through what could be called the heating sector (3). After the preheated and heated part of the fresh air is mixed and thus its required delivery temperature is reached, it is conveyed by the compressor (5) to the space to be heated (9).

This side could be called the fresh air side.

On the other spent air side (SA) of the heat exchanger, the air to be expelled is drawn from the space (9) and as in the case of the fresh air, split up in two flows. The by far larger (80-90%) passing through the peripheral sector of the heat exchanger, the airpreheater (2) and the smaller part, after having been heated by the combustion of a preferably gaseous fuel in the combustion chamber (4), passes through the central sector (3) the air heater of the heat exchanger combination.

Finally, the two spent air flows coming from the preheater and heater sector are mixed and then exhausted by the compressor (6) to the atmosphere.

Instead of at the outlet of the fresh air side, the compressor (5) can also be arranged at its inlet. Similarly the spent air compressor (6) can also be arranged at the inlet instead of the outlet of the spent air side. Furthermore, each of the compressors can be driven individually or both compressors can be driven by a common power device suqh as an electric motor.

Preferably means for controlling the speed of the motor should be available.

In accordance to the invention a cooling capability is added to such a heating and ventilating unit. This is achieved by arranging at the inlet of the spent air side of the heat exchanger, an expander (turbine) (10) as well as flow regulating valve (11). The expander (10) can be linked via a coupling (12) with the electric motor (8) driving the spent air side compressor (6).

Whereas in the case of heating, this expander is by-passed by positioning the valve (11) in an appropriate way, and by separating the expander (10) by use- of the coupling (12) from the electric motor (8). Thus the expander is by-passed as far as the flow of the spent air is concerned.

By re-setting the valve (11) and linking the expander (10) through the coupling (12) with the electric motor (8), the spent air flows through the expander where the temperature of this air is reduced, depending on the speed of the electric motor (8). From the expander the spent air passes through sector (2) and (3) of the spent air side of the heat exchanging matrix, its pressure then being raised to atmospheric in the compressor (6) before being expelled. Due to the regenerative heat exchange process, the fresh air flowing through sectors (2) and (3) of the fresh air side is cooled before being conveyed by the compressor (5) into the space (9).

Of course during such cooling period the combustion chambers is out of action. Seeing that most of the air flows through the sectors (2) of the heat exchanger, it is possible by the arrangement of two valves, one at the inlet of the fresh air side and one at the inlet of the spent air side to eliminate flow through the central sector (3) of the matrix.

Therefore by the addition of an expander (turbine), a flow regulating valve (11) and a coupling (12), the heating and ventilating unit can be converted into a heating, cooling and ventilating unit, and this enables it to give a full air conditioning service.

1. Heating and ventilating unit consisting of a regenerative heat exchanger (1), its heat exchanging part, the matrix, being contained in a

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION A regenerative air conditioning unit with waste heat recovery As the envelope of a building is made tighter thus reducing heat losses through the fabric as well as due to uncontrolled ventilation, controlled ventilation, i.e. a continuous replacement of stale air by fresh air becomes essential, otherwise not only condensation but also hazards to health can occur. In other words, "tighter" walls, doors and windows require a controlled ventilation. Increasingly not only heating in winter but cooling in supper is the prerequisite of a healthy environment in the rooms of a building. The increased use of electronic devices for all sorts of purposes increase the heat generated and the need to cool. In accordance with the invention, a cooling capability is added to a heating and ventilating unit as described in detail in patent application No. 8227321. Such a unit consists (see Fig. 1) of a regenerative heat exchanger, its heat exchanging part, the matrix, is contained in a rotating disc (1) made from a ceramic engineering material. This matrix in turn consists of a multitude of small flow channels surrounded by thin walls. Two circular sectors, a peripheral (2) and a central (3) are foreseen fulfilling different heat exchanging functions. Furthermore, there is a combustion chamber (4) as well as two preferably single stage radial compressors (blowers) (5) and (6) driven by electric motors (7) and (8) respectively, together with the auxiliaries for driving the disc, for injecting and controlling the fuel for ignition and its control and so on. Instead of two circular sectors three can be arranged in such a way that the colder air flows through the inner and outer sectors and the hotter through the central sector. The operation of such a heating and ventilating unit is such that the by far largest portion (80-90%) of the fresh air (FA) passes through what could be called the airpreheating sector (2) and the rest 10-20% through what could be called the heating sector (3). After the preheated and heated part of the fresh air is mixed and thus its required delivery temperature is reached, it is conveyed by the compressor (5) to the space to be heated (9). This side could be called the fresh air side. On the other spent air side (SA) of the heat exchanger, the air to be expelled is drawn from the space (9) and as in the case of the fresh air, split up in two flows. The by far larger (80-90%) passing through the peripheral sector of the heat exchanger, the airpreheater (2) and the smaller part, after having been heated by the combustion of a preferably gaseous fuel in the combustion chamber (4), passes through the central sector (3) the air heater of the heat exchanger combination. Finally, the two spent air flows coming from the preheater and heater sector are mixed and then exhausted by the compressor (6) to the atmosphere. Instead of at the outlet of the fresh air side, the compressor (5) can also be arranged at its inlet. Similarly the spent air compressor (6) can also be arranged at the inlet instead of the outlet of the spent air side. Furthermore, each of the compressors can be driven individually or both compressors can be driven by a common power device suqh as an electric motor. Preferably means for controlling the speed of the motor should be available. In accordance to the invention a cooling capability is added to such a heating and ventilating unit. This is achieved by arranging at the inlet of the spent air side of the heat exchanger, an expander (turbine) (10) as well as flow regulating valve (11). The expander (10) can be linked via a coupling (12) with the electric motor (8) driving the spent air side compressor (6). Whereas in the case of heating, this expander is by-passed by positioning the valve (11) in an appropriate way, and by separating the expander (10) by use- of the coupling (12) from the electric motor (8). Thus the expander is by-passed as far as the flow of the spent air is concerned. By re-setting the valve (11) and linking the expander (10) through the coupling (12) with the electric motor (8), the spent air flows through the expander where the temperature of this air is reduced, depending on the speed of the electric motor (8). From the expander the spent air passes through sector (2) and (3) of the spent air side of the heat exchanging matrix, its pressure then being raised to atmospheric in the compressor (6) before being expelled. Due to the regenerative heat exchange process, the fresh air flowing through sectors (2) and (3) of the fresh air side is cooled before being conveyed by the compressor (5) into the space (9). Of course during such cooling period the combustion chambers is out of action. Seeing that most of the air flows through the sectors (2) of the heat exchanger, it is possible by the arrangement of two valves, one at the inlet of the fresh air side and one at the inlet of the spent air side to eliminate flow through the central sector (3) of the matrix. Therefore by the addition of an expander (turbine), a flow regulating valve (11) and a coupling (12), the heating and ventilating unit can be converted into a heating, cooling and ventilating unit, and this enables it to give a full air conditioning service. CLAIMS

1. Heating and ventilating unit consisting of a regenerative heat exchanger (1), its heat exchanging part, the matrix, being contained in a rotating disc (1) preferably made from a ceramic engineering material, this matrix sub-divided into at least two circular sectors (2), (3), fulfilling different heat exchanging functions, a combustion chamber (4), two preferably single stage radial compressors (blowers) (5), (6), driven by electric motors (7), (8), and the auxiliaries required for driving the disc and controlling the performance of the said unit, characterised by a cooling capability achieved by expanding the spent air, thus reducing its temperature before passing through the matrix (2), (3), of the heat exchanger (1), and raising the pressure of the spent air after leaving this matrix to the atmospheric in a compressor (6) before being expelled to the atmosphere.

2. A heating, cooling and ventilating unit in accordance to claim 1 incorporating an expander (turbine) (10), a valve (11) permitting regulation of the flow of the spent air and a coupling (12) between the expander and the electric motor (8) driving the compressor (6).

3. Unit in accordance with claims 1 and 2 where for heating operation the valve (11) is set so that the flow of the spent air bypasses the expander (10) with the coupling (12) being disengaged.

4. Unit in accordance to claims 1 and 2 where for cooling operation the valve (11) is set so that the flow of the spent air passes through the expander (10) with the coupling (12) engaged, and after leaving the expander flows through the matrix (2), (3), of the heat exchanger (1) before its pressure is raised in the compressor (6) to the atmospheric.

5. Unit in accordance to claims 1-4 where compressors (5) and (6) as well as expander (10) are driven by one electric motor (8).

6. Unit in accordance to claims 1-4 where the electric motor (8) can be speed controlled.