GB2260191A

GB2260191A - Cooling air

Info

Publication number: GB2260191A
Application number: GB9120948A
Authority: GB
Inventors: W Hrynlazak
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-10-02
Filing date: 1991-10-02
Publication date: 1993-04-07
Also published as: GB9120948D0

Abstract

In a process for cooling air a regenerative or recuperative heat exchanger 1 is combined with an electric heat pump 2 which works on the Peltier principle in an energy saving way. This process can be used to dehumidify air or to cool spaces with forced ventilation, and waste "cold" recovery. <IMAGE>

Description

COOLING WITH WASTE "COLD" RECOVERY.

It is generally recognised that by saving heat otherwise wasted in a thermodynamic cycle for example by recycling it in an efficient way, to a considerable extent reductions in energy consumption are possible.

However, adopting a similar process when cooling is involved can lead to even more desirable results; after all the different methods of cooling are usually more energy consuming that when heating. Especially if cooling devices such as the electric heat pumps employing what is called a Peltier device are used, the modules of such devices being relatively expensive, reducing the electric input required by the device is of great importance.

In accordance with the invention this is achieved by combining a regenerative or recuperative heat exchanger (1) with an electric heat pump (2) in such a way that the air moved by a blower (3) after passing through the cooling side (4) of the heat exchanger flows through the cooling side (5) of the heat pump , such process leading to a two-step reduction in the temperature of the air.

On the other hand air, usually at such low temperature after passing through the heating side (6) of the heat exchanger is partly or fully used to remove the heat generated on the heating side (7) of the heat pump. Between the cooling and tht heating side of this heat pump the module (8) is situated.

Therefore a very efficient basis for cooling in an economical way has been created.

Instead of blowing, extracting of the air can be employed. Media other than air may be involved in the process mentioned above.

One application of the thermodynamic process just described is shown in Fig.2.

In this case the wet air provided by the blower (3) passes through the cooling side (4) of the regenerative heat exchanger (1) driven by way of example by a belt (8) a pinion (9) and an electric motor (10), then the temperature of the cooled air is further reduced in the cooling side (5) of the electric heat pump (2).

This cooling side could consist of a number of fins through which the air flows, these fins being cooled by the module (8).

In a separator (11) the condensed water is extracted and the air is then passed through the heating side (6) of the heat exchanger, is then directed through the heating side (7) of the heat pump, this again consisting of a number of fins through which the air passes before returning in a more or less dry state back to the space from which the wet air was taken.

A further advantage of the process is that the temperature of the dry air is about the same as that of the wet air, so no heat is lost.

From a control point of vlew two phases can be distinguished. The first phase exploits the full cooling capacity of the heat pump: after a number of revolutions of the regenerative heat exchanger disc the desired end temperature of the air has been reached and at this stage and as a second phase of operation, the cooling effect of the heat pump has to be turned back to a point where stable conditions are being maintained.

The rotational speed of the disc can additionally be used to further extend controllability, For environmental reasons the trend is towards avoiding the use of refrigerants especially chlorofluorocarbons when it comes to cooling say of air. In view of the importance to offer complete air conditioning, that means heating or cooling of air together with forced ventilation, adding cooling to an already existing appliance becomes more and more attractive. In many cases such a heating capability exists in one form or another and what is required is to add to it a cooling appliance avoiding the use of refrigerants.

The basic thermodynamic process as described (Fig.l) allows the design of such an additional cooling appliance (Fig.2). The blower (3) conveys fresh air through the cooling side (4) of a recuperative heat exchanger (1), further cooling takes place in the electric heat pump (2), such cooling mainly catering for the heat gain in the space to be cooled. The stale air from the space passes through the heating side (6) of the heat exchanger; the movement of the air being supported by an extractor (12). This stale air is then used as already described to remove the heat from the electric heat pump. The two fans (3) and (12) can be jointly driven by an electric motor (13).

Fig. 4 shows schematically a frontal view of the recuperative heat exchanger together with the arrangement of the electric heat pump with the two modules (8), the cooling side with its horizontal fins in the centre and the two heating sides (7) with their vertical fins.

In such a way a small compact unit with low energy consumption can be created for the purpose visualised.

Claims

CLAIMS.

1. Process for cooling with waste "cold" recovery characterised by combining a heat exchanger with an electric heat pump which works on the Peltier principle in such a way that the air moved by a blower after passing through the cooling side of the heat exchanger flows through the cooling side of the heat pump, the cooling side being characterised by a temperature drop and where the heat is removed from the heating side of the heat pump by air leaving the heating side of the heat exchanger, the heating side being characterised by a temperature rise.

2. Dehumidifier using a process in accordance to Claim 1 whereby in a single circuit the wet air is moved by the blower through the cooling side of the heat exchanger and that of the heat pump and where a separator arranged after the cooling side of the heat pump extracts the water from the air and where the thus dried air after being heated in the heating side of the heat exchanger is further heated to more or less its original temperature in the heating side of the heat pump.

3. Dehumidifier in accordance to Claim 2 where a regenerative heat exchanger is used and where the control is such that the heat pump is initially used to its full capacity until after a number of revolutions of the rotor the desired operating conditions have been reached and where then the cooling effect of the heat pump is adjusted in accordance.

CLAIMS (contd).

4. Dehumidifier in accordance to Claim 3 where the speed of the rotor of the heat exchanger is adjusted so as to achieve optimum performance together with optimum controllability.

5. Air cooling for air conditioning with forced ventilation using a process in accordance to Claim 1 where two circuits are used, one for the fresh incoming air, the other for the stale outgoing air, and where the fresh air is pushed by a blower through the circuit in such a way that it is first cooled - in the cooling side of the heat exchanger and then in the cooling side of the heat pump before being distributed in the space to be air conditioned and where the stale air taken out of this space is sucked by a blower through the heating side of the heat pump.

6. In accordance to Claim 5 where the cooling in the heat pump mainly caters for the heat gains through the walls of the space to be air conditioned.

7. Air cooling for air conditioning with forced ventilation using a process in accordance to Claim 5 where the impeller of the pushing blower and that of the extracting blower are rotated by one common electric motor.