IL107008A

IL107008A - Combined cooling and heating process and equipment for room air conditioning

Info

Publication number: IL107008A
Application number: IL10700893A
Authority: IL
Original assignee: Hagenuk Fahrzeugklima Gmbh; Normalair Garrett Ltd
Priority date: 1992-10-14
Filing date: 1993-09-14
Publication date: 1996-03-31
Also published as: IL107008A0; JP2635287B2; EP0592833B1; CA2108501A1; ES2114579T3; ATE162608T1; RU2062964C1; DE4235217C2; EP0592833A1; DE59308030D1; DK0592833T3; DE4235217A1; JPH06213521A

Abstract

The invention relates to a combined cooling and heating process for air-conditioning a compartment (8) and also to a device for carrying out the process, in particular for use in passenger train carriages. With this process and device, it is possible to either cool or heat a compartment (8). If the compartment (8) is no longer to be cooled but heated, according to the invention two valves (23, 24) are reversed, and the process air flows through the units required for cooling, heat exchanger (5) and regenerator (6), without heat exchange. The air heated by the compressor (2, 3) passes to the useful-heat exchanger (7) via a bypass pipe (31). The air cooled in the useful-heat exchanger (7) but still under pressure is conveyed via a further bypass pipe (22) to a turbine (4), where it is relieved of pressure and is released to the environment. The air of the compartment (8) to be heated is here sucked in by a pre-compressor. <IMAGE>

Description

Tina PROCESS COMBINED COOLING AND HEATING Φ-Β€» ίφϋ« AND EQUIPMENT FOR ROOM AIR CONDITIONING HAGENUK FAHRZEUGKLIMA GMBH NORMALAIR-GARRETT LTD.

Combined cooling and heating technique and equipment for room air conditioning Description The invention concerns a combined cooling and heating process for room air conditioning as well as a device to carry out the technique, especially for use in passenger trains .

The task of cold air units is to cool a room by using thermodynaiuic properties of air in a Joule cycle. Several methods have been known to carry out this process. A single expansion machine-engine-set as well as two ambient heat exchangers on the warm and the cold side (Bosnjakowic: "Technische Thermodynamic" , part 1, 4th edition, Leipzig and Dresden, p. 291 - 295). To improve the efficiency this basic technique has been further supplemented by multistage compression with and without intermediate cooler, with regenerative heat exchange, by opening the cyclic process on the cold, the warm or on either side (Kauffeld, KiSnig, ruse; "Luft als κalt«f-ittel,,, 1991, . 217 - 237.

Another improvement 1st described in DE-PS 31 39 398, where in an open cold air unit process with two-stage compression the air humidity condensing in the aftercooler is at least partly conducted back regenerafcively to the process in front of the compressor ot the second sta e, to ake use of the energ nnntpnt nf the water by evaporating and thus to improve the efficiency of the unit, Any of these techniques have the disadvantage tnat they need more motive energy per refrigeration than comparable cold air unit processes, so that their application is restricted to special cases.

Cold air units are frequently used for cooling plane cabines. There is the energetic advantage that the difference of the capacities of the turbine and compressor is produced by supplying compressed engine air, which must already be generated for the functioning of the engine. Otherwise supplying energy by means of a process of combustion has proven to be too expensive.

In DE-PS 38 37 052 this solution has been supplemented by a technique for producing heat and cold simultaneously with energy supply in a combustion chamber, two turbine-expansion machine sets and corresponding heat exchangers. This method has the disadvantage that there must be a need for both heat and cold, even though it is possible to shift the capacities to a certain extent by switching on a store. This, however, affects energetic effectiveness.

The invention is based on the task to develop a technique and a device for air conditioning a room, which can be used either for heating or for cooling and with which the annual energy consumption can be decreased considerably.

The present invention thus consists in a combined cooling and heating process for room air conditioning, during which the room is no longer cooled but heated by switching over valves, heat exchanger and regenerator are switched off and process air flows through them without heat exchange, with the characteristic that the air heated by compressor gets to load heat exchanger via a bypass line and the air cooled down in the load heat exchanger but still under pressure is conducted to the inlet side of the turbine via another b - ass line and iven off to the outside via switch In a preferred embodiment, the condensing water of the supply air consisting of return air and fresh air, which is obtained during the cooling process in load heat exchanger, is conducted together with the exhaust air to regenerator via pipe, possibly by switching in a pump.

The present invention also consists in a device for carrying out the above process with a motor-driven pre-compressor, a combined compressor-turbine-unit with interposed heat exchanger consisting of ambient heat exchanger and regenerator, subsequently added load heat exchanger for cooling supply air of the room to be air conditioned, and corresponding connecting pipes, with the characteristic that between the outlet side of ambient heat exchanger and the inlet side of load heat exchanger there is a by-pass line with a switch valve and between the outlet side of load exchanger and the inlet side of turbine there is a by-pass line with a switch valve.

The technique invented is a combined cooling and heating process for air conditioning a room, especially of passenger trains, according to which either cooling or heating can be applied. When the room shall no longer be cooled or heated, two valves are switched and the process air flows through the sets necessary for cooling, heat exchanger and regenerators without heat exchange. The air heated by the compressor flows to the load heat exchanger via a by-pass line. The air cooled down in the load heat following, the invention will be explained in a more detailed way by means of examples of operation.

In the drawing, the following is showni Figure 1: circuit scheme for cooling a room Figure 2i circuit cohomc for heating a veem The unit consists of a pre-compreesor 2 driven by an electric motor 1, a compressor 3 switched as second stage, which is driven by the expansion turbine 4.

Furthermore there are an ambient heat exchanger 5 with regenerator 6 between compressor 3 and turbine 4 and a load heat exchanger 7 for eeding air of room 8 cnnduflfcfiri hy fan 18 via ducts 15 and 16 is also cooled by heat exchange. The efficieny of regenerator 6 is improved by supplying the air humidity condensing in load heat exchanger 7 via pipe 32 to it. The share of fresh air necessary for room 8 is sucked from the outside via duct 20 by adjusting flap 19 accordingly. The exhaust aix &LjitHuuf the vulmue of which corresponds to the fresh air stream, flows via duct 17 to jjejwiie-LciLot δ and there it improves the 'cooling effect achieved in heat exchanger 5. The air from pipe 14 heated in the load heat exchanger flows to compressor 2 via pipe 14. Thus, the circuit is closed.

For the heating process according to figure 2 valves 23 and 24 are switched over and the efficiency of heat exchanger 5 and regenerator 6 is eliminated, so that the air heated by the compressor flows to load heat exchanger 7 via by-pass line 31 and pipe 13 and then to the turbine via another by-pass line 22. The expanded air gets to the outside via pipe 12 by switching over valve 25 via pipe 26. The air of room 8 is heated in the load heat exchanger 7. The share of fresh air coming in at opening 20 gets to the inlet of compressor 2 by switching over valve 27 via pipes 30 and 14. At opening 29 compressor 2 sucks air from the outside if valve 28 is switched over. In this case room 8 is not supplied with fresh air during heating . - 6 -

Claims

1. Combined cooling and heating process for room air conditioning, during which the room is no longer cooled but heated by switching over valves, heat exchanger and regenerator are switched off and process air flows through them without heat exchange, with the characteris- tic that the air heated by compressor gets to load heat exchanger via a by-pass line and the air cooled down in the load heat exchanger but still under pressure is conducted to the inlet side of the turbine via another by-pass line and given off to the outside via switch valve and pipe. Process Teokni-que according to claim 1, with the characteristic that the condensing water of the supply air consisting of return air and fresh air, which is obtained during the cooling process in load heat exchanger, is conducted together with the exhaust air to regenerator via pipe, possibly by switching in a pump. , process Device to carry out the teohn- tes according to ciaim^ 1 or •end- 2 with a motor-driven pre-compressor, a combined compressor-turbine-unit with interposed heat exchanger consisting of ambient heat exchanger and regenerator, subsequently added load heat exchanger for cooling supply air of the room to be air conditioned, and corresponding connecting pipes, with the characteristic that between the outlet side of ambient heat exchanger and the inlet side of load heat exchanger there is a by-pass line with a switch valve and between the outlet side of load exchanger and the inlet side of turbine there is a bypass line with a switch valve.