WO1999058398A1

WO1999058398A1 - A system for air-conditioning environments, particularly cabins on board ships and barges

Info

Publication number: WO1999058398A1
Application number: PCT/IT1999/000127
Authority: WO
Inventors: Stefano Udina
Original assignee: Fincantieri Cantieri Navali Italiani S.P.A.
Priority date: 1998-05-11
Filing date: 1999-05-11
Publication date: 1999-11-18
Also published as: EP1076626B1; ITPD980111A1; DE69905032D1; DE69905032T2; ATE231459T1; EP1076626A1; AU3847499A

Abstract

The air-conditioning of environments such as cabins on passenger ships is performed by means of a static cooling system. Water, particularly chilled water, is used directly for bringing about the thermal exchanges necessary to reduce the temperature in the environment, and is circulated through radiators (1) or similar heat-exchange units disposed in the region of at least one of the walls (W) of the environment to be air-conditioned. There is also provision for possible combination with means (6 to 8) for the supply of a limited quantity of air to the environment in order to ensure the oxygen content, humidity and temperature necessary for the general comfort of the occupants.

Description

1 A SYSTEM FOR AIR-CONDITIONING ENVIRONMENTS, PARTICULARLY CABINS ON BOARD SHIPS AND BARGES TECHNICAL FIELD

The present invention relates to systems for air-conditioning environments and has been developed with particular attention to its use for air-conditioning environments such as, for example, cabins on board large and small ships, barges of various types, etc... TECHNICAL BACKGROUND At the moment, the selection conventionally adopted for air- conditioning (or climate-control, the two terms are used herein as being equivalent to one another) is that of distributing into the environment air which is produced in suitable production centres and is then distributed to various environments by means of distribution ducts.

Although broadly successful, this solution has a whole series of disadvantages, such as:

- the poor efficiency of the thermal exchange performed by means of air which is a poor conductor, - the considerable space taken up by the air-conditioning stations and by the ducts, which results in a reduction in the useful space available on board,

- the overall size, and considerable weight, of the ducts used for distributing the air and of the stations for producing the air (air-conditioning stations) which require the installation of heavy machinery,

- the noise resulting from the flow of large amounts of air through the distribution ducts, and

- the intrinsic complexity of the system which also has adverse effects in terms of maintenance costs. 2

DESCRIPTION OF THE INVENTION

The object of the present invention is to provide an innovative system for air-conditioning environments of this type which can eliminate the above-mentioned disadvantages. According to the present invention, this object is achieved by means of a system for air-conditioning environments having the characteristics recited in the following claims. Briefly, the system according to the invention is based on the use of the technique known as "static cooling" which provides for the direct use of a diathermic liquid, typically water, for performing the thermal exchanges necessary to condition the climate-controlled environments. When, as is most usual, the environments are to be cooled, the water is used directly for rendering some surfaces such as ceilings and/or floors colder than the environment to be conditioned. The thermal exchange is much more effective than that with air - which is a poor conductor of heat - offering many advantages in comparison with the conventional solution. The solution according to the invention can be used in combination with a system for conveying air to the environments to be conditioned. In this case, however, it is possible to reduce the amount of air supplied to the smallest quantity which suffices to ensure the oxygen content, humidity and temperature necessary for general comfort in the air-conditioned environment.

The advantages of the solution according to the invention can be summarized in the following terms. In the first place, it is possible to achieve a considerable overall energy saving (tests carried out by the Applicant indicate an energy saving of the order of 40%) in comparison 3 with conventional systems. This saving is achieved not only by the greater efficiency of the thermal exchanges which are performed with water instead of with air, but also by the fact that, on many occasions, it is possible to perform natural cooling with water, without the need to use water cooled positively by means of a refrigeration machine (chilled water) .

In the second place, the invention achieves a considerable reduction in weight since the air-distribution ducts can be replaced by small water-distribution pipes. Moreover, the fact that the air-conditioning stations are eliminated, with the consequent elimination of heavy machinery for producing cooled air, is al1- important . In the shipping field and particularly for passenger ships, the reduction in weight offers a considerable competitive advantage.

Moreover, the invention achieves a considerable reduction in the space occupied by the air-conditioning stations in the central regions of the ship in which the cabins and public rooms are located, permitting a considerable increase in useful space (so-called "marketable" space) .

The solution according to the invention achieves static thermal exchanges without artificial air movement and is therefore intrinsically quiet. Further advantages of the invention can be attributed to a reduction in overall costs on account of the simplification of the system, and a reduction in maintenance problems (a reduction in the number of machines necessary, a reduction in insulating masses, reduced use of control locks, etc.), and to a general improvement in comfort on board both on account of the noise attenuation and on account of more natural heat 4 exchanges which are appreciated in the form of greater comfort for the human body.

In summary, the application of the "static cooling" technique in the shipping field, for example, in passenger ships, adds to the overall advantages that of increasing the marketable space, with considerable advantages from the technical point of view since it permits the use of a single circuit for controlling the oxygen, the humidity, and the temperature in the environments, and with considerable benefits in terms of comfort and weight . Advantages are also achieved in terms of the operation of the craft since problems of the maintenance and regulation of the systems are reduced to the minimum. BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described, purely by way of non- limiting example, with reference to the appended drawings, in which:

Figure 1 is a general plan view of a cabin of a craft provided with an air-conditioning system according to the invention, and Figure 2 shows the specific characteristics of the system according to the invention in greater detail . PREFERRED EMBODIMENT OF THE INVENTION

As already stated, the view of Figure 1 corresponds to a general plan view of a cabin situated on board a ship or a barge; typically it may be a passenger cabin on board a merchant ship of any type.

Of the cabin, which is generally indicated C and has a portion or room T for sanitary facilities, Figure 1 shows the floor P, which is covered by a set of strips so as to give rise to a structure which is reproduced in almost identical 5 manner in the ceiling W of the cabin, part of which is shown in Figure 2.

As will be explained further below, the solution according to the invention is based upon the concept of the use of at least one of the walls of the cabin C (and hence the floor P and/or the ceiling W and/or any of the other walls of the cabin C) to perform a thermal exchange with a diathermic fluid, typically water, in the manner illustrated in detail in Figure 2 with reference to the ceiling W. These surfaces, which are colder than the environment to be conditioned by about 10°C, absorb the heat according to need, unlike conventional systems which admit cold air to the environment. It is, however, intended that the solution shown in the drawing with reference to the ceiling W may be transferred in almost identical manner to any one of the other walls of the cabin C.

If Figure 2 is examined in greater detail, it can be seen that the strips D forming the covering of the ceiling W carry, immediately above them, associated heat-exchange units, typically configured as radiators 1. These are preferably finned radiators such as those used, for example, as heat-exchangers in motor-vehicle cooling or air- conditioning systems or in air-conditioners, etc. The radiators 1 are preferably disposed immediately behind the strips D which, also preferably, are usually made of metallic material so as to improve the thermal exchange. The radiators 1 are connected in a network for the circulation of water which is preferably positively cooled (chilled water) . The water-circulation network comprises, in the portion of the system visible in Figure 2, a delivery pipe 2 and a 6 return pipe 3 from which respective local distribution delivery and return pipes 4 and 5, respectively, branch out. It will, however, be appreciated that the solution shown in the drawing, in which the radiators 1 are concealed from the exterior by the strips D, is not essential. In fact it is possible to consider configuring the radiators 1, at least on their lower faces, in a manner such that they can be exposed directly to the environment to be conditioned. Similarly, although the use of radiators 1 such as the finned radiators shown in Figure 2 is preferable, it is not essential; an effective exchange function can also be achieved simply by configuring the water-distribution network in the form of a coil of small-diameter tubes forming a water-distribution network spread out over the wall which is represented, in the embodiment shown, by the ceiling W.

The main delivery and return pipes 2 and 3 are connected to a station for the supply of water which, as already indicated above, is usually constituted by chilled water produced in one or more centralized cooling stations (not shown but of known type) fitted on board the ship or the barge. It will however, be appreciated that, at least in environmental conditions which are not particularly critical, effective air-conditioning can be achieved simply by circulating water at the temperature at which it is stored on board (or at the temperature at which it is drawn from the expanse of water in which the ship or barge is disposed at the time in question, possibly after desalination/filtering) and hence without the need for an operation to reduce its temperature positively with the resulting energy absorption. An air-distribution pipe, indicated 6, is connected, by means of a respective local distribution pipe 7, to a diffuser 8 7 (preferably of the silenced type) which opens into the cabin C, so that it is possible in any case to ensure that the cabin is supplied with a minimum quantity of air which suffices to ensure the oxygen content, humidity and temperature which can ensure the general comfort of the people occupying the cabin.

Naturally, the principle of the invention remaining the same, the details of construction and forms of embodiment may be varied widely with respect to those described and illustrated, without thereby departing from the scope of the present invention.

Claims

1. A system for air-conditioning environments, particularly cabins on board ships and barges, characterized in that it comprises, in the region of at least one (W) of the walls of the environment, heat-exchange means (1) supplied with a diathermic liquid such as water.

2. A system according to Claim 1, characterized in that it comprises distribution means (2, 3) for supplying chilled water to the heat-exchange means (1) in order to bring about the thermal exchanges necessary to reduce the temperature in the air-conditioned environment.

3. A system according to Claim 1 or Claim 2, characterized in that the heat-exchange means (1) comprise radiators (1) .

4. A system according to Claim 3, characterized in that the radiators (1) are finned radiators.

5. A system according to any one of the preceding claims, characterized in that the heat-exchange means (1) are located in a position adjacent the at least one wall (W) of the environment to be air-conditioned and are concealed from view by facing elements (D) of thermally conductive material.

6. A system according to any one of the preceding claims, characterized in that it further comprises means (6 to 8) for diffusing air into the air-conditioned environment in controlled quantities.

7. A system according to any one of the preceding claims, characterized in that the heat-exchange means (1) are associated with the ceiling (W) of the environment to be air- conditioned.