Apparatus for cyclic air supply into a room with standard and high flow-rate

Abstract

 An apparatus for conducting supply air into an inside space of a building, more particularly into a room, wherein the supply air is arranged to flow for most of the time with a certain air volume, which apparatus comprises at least a first supply air pipe (1), which comprises apertures or nozzles (3) for conducting air into a room. The invention is implemented such that the apparatus comprises at least one second supply air pipe (2), or part of a supply air pipe, which comprises more apertures or nozzles (3) than the first supply air pipe (1).

Description

[0001] The object of this invention is an apparatus for conducting supply air into an inside space of a building, more particularly into a room, wherein the supply air is arranged to flow for most of the time with a certain air volume, which apparatus comprises at least a first supply air pipe, which comprises apertures or nozzles for conducting air into a room.

[0002] The ventilation of an inside space of a building, such as a room, more particularly a classroom, an office or a corresponding space, which typically contains numerous people, is challenging. People generate a thermal load, which endeavors to gradually raise the inside temperature of the room. To compensate this, there are in principle two solutions: the room can be cooled mechanically, or more air can be supplied to the room. Mechanical cooling is rather expensive to install and consumes a lot of energy. Additional (uncooled) air flow can, for its part, result in air flow velocities that are too high, which produce discomfort and a continuous draft for those people in the room.

[0003] Hans Wigö's doctoral thesis "Technique and human perception of intermittent air velocity variation, September 2005, University of Gavle, Sweden" has investigated these problems. The doctoral thesis endeavors to show that it is, in fact, more pleasant for people in a room if momentarily "excess" air flows into the room. This more abundant air flow can last for e.g. five minutes, after which a smaller amount of air is brought to the room for e.g. 15 minutes. An abundant air flow for five minutes was experienced as cooling and the feeling of an unpleasant draft was not experienced. The temperature does not in this case need to be mechanically cooled, but instead sufficiently pleasant indoor air was achieved.

[0004] The aim of this invention is to apply the concept of a stronger supply air flow occurring intermittently as presented in the aforementioned doctoral thesis. This is achieved with an apparatus that is characterized in that the apparatus also comprises at least one second supply air pipe, or part of a supply air pipe, which comprises more apertures or nozzles than the first supply air pipe.

[0005] One preferred embodiment of the apparatus according to the invention is characterized in that the second supply air pipe, or part of a supply air pipe, comprises 6-8 times more apertures or nozzles than the first supply air pipe.

[0006] A second preferred embodiment of the apparatus according to the invention is characterized in that the first supply air pipe and the second supply air pipe are disposed side-by-side, in which case air is conducted into them alternately in turns at certain regular intervals.

[0007] Yet a third preferred embodiment of the apparatus according to the invention is characterized in that the first supply air pipe and the second supply air pipe are disposed one after the other such that at first in the flow direction of the air is the aforementioned first supply air pipe and after it the aforementioned second supply air pipe is fixed, and in that an openable and adjustable valve is disposed between them, in which case the valve is in the open position when more supply air is desired and in the closed position when less supply air is desired.

[0008] One of the advantages of the invention is that with a simple apparatus the distribution of supply air can be implemented in pulses, i.e. at times more air, at times less, at certain regular intervals.

[0009] In the following, the invention will be described in more detail by the aid of some preferred embodiments with reference to the attached drawings, wherein

Fig. 1 presents a simplified embodiment of the invention, wherein the first supply air pipe and the second supply air pipe are disposed one after the other.

Fig. 2 presents a simplified embodiment of the invention, wherein the first supply air pipe and the second supply air pipe are disposed side-by-side.

[0010] In the invention the technology presented in the aforementioned doctoral thesis is utilized in the form of a concrete apparatus. The principle of the technology in question is thus that supply air is brought into the inside space of a building, e.g. into a room, which can be e.g. a classroom or corresponding, for a certain time e.g. 15 minutes. After it, considerably more supply air is brought, e.g. for five minutes. Although the temperature of the room is not cooled any more than before as measured by a thermometer, the persons in the room experience the air pulses as pleasantly cooling, and do not experience the feeling of a draft. The aforementioned duration times of the air flows can be varied, but the basic principle is that the basic flow always lasts longer than the stronger flow.

[0011] The apparatus according to the invention is presented in the figures in simplified form. Fig. 1 presents a first supply air pipe 1 and a second supply air pipe 2, which are connected to each other one after the other. The joint of the pipes is presented with the reference number 4. The flow direction of the supply air is marked with an arrow V. A valve is between the supply air pipes 1 and 2, which valve is not shown in the drawings. By means of the valve the flow connection of the supply air pipes can be opened and closed.

[0012] The first supply air pipe 1 is e.g. a supply air pipe of FläktWoods Oy's UNO system, which is in itself known in the art and which comprises nozzles 3 in a row in the longitudinal direction of the pipe. The nozzles are formed from nine nozzle units containing nine small nozzle apertures. These types of nozzle units are disposed at regular intervals in the longitudinal direction of the pipe. In normal use only this type of supply air pipe is used, in which case the small air jets of the nozzles are mixed effectively into the room air. In this situation the valve between the supply air pipes 1 and 2 is closed, in which case air is not able to flow into the second supply air pipe.

[0013] When the smaller air volume has been supplied for a certain period of time, e.g. 15 minutes, the valve between the supply air pipes 1 and 2 is opened, in which case is able to flow also into the second supply air pipe 2. As is observed from the drawings, this supply air pipe 2 comprises a number of rows of nozzles 3. There can be 6-8 times more of them than in the first supply air pipe 1. This can vary to a greater extent also, but the principle is that the apparatus comprises one or more second supply air pipes 2, or parts of a pipe, in which there are manifestly more nozzles than in the first supply air pipe 1.

[0014] The nozzle rows are disposed e.g. at essentially regular intervals on the rim of the supply air pipe. Their more accurate placement and number can be determined according to need. In any case the second supply air pipe gives a considerably stronger supply air flow into the room. This stronger air flow can be continued e.g. for five minutes, after which the valve between the supply air pipes 1 and 2 is closed again and the supply air flow decreases to the basic flow again. After this the supply of the supply air is continued following the same pattern.

[0015] Fig. 2 presents a second embodiment of the invention, wherein the first supply air pipe 1 and the second supply air pipe 2 are disposed side-by-side. These are connected to a supply air duct, which is not shown. Neither are the valve or splitter, with which the supply air flow is conducted into these pipes, shown. Such a valve or splitter is, however, easy for a person skilled in the art to implement.

[0016] The principle of the embodiment according to Fig. 2 is the same as in the preceding embodiment. Air is supplied e.g. for 15 minutes via the first supply air pipe, after which the air flow is connected to come via the second supply air pipe e.g. for five minutes. In this case for a period of five minutes considerably more air comes into the room. After that the basic air flow is again connected via the first supply air pipe for 15 minutes, and so on.

[0017] It is obvious to the person skilled in the art that the invention is not limited to the embodiments presented above, but that it can be varied within the scope of the claims presented below. Thus the supply air pipes do not need to be exactly of the type presented in the drawings. For example, the number, alignment and size of the nozzles 3 can be varied according to need. Likewise, it is possible that there are a number of such inlet pipes in different parts of the room.

Claims

1. An apparatus for conducting supply air into an inside space of a building, more particularly into a room, wherein the supply air is arranged to flow for most of the time with a certain air volume, which apparatus comprises at least a first supply air pipe (1), which comprises apertures or nozzles (3) for conducting air into a room, characterized in that the apparatus comprises at least one second supply air pipe (2), or part of a supply air pipe, which comprises more apertures or nozzles (3) than the first supply air pipe (1).

2. Apparatus according to claim 1, characterized in that the second supply air pipe (2), or part of a supply air pipe, comprises 6-8 times more apertures or nozzles (3) than the first supply air pipe.

3. Apparatus according to claim 1 or 2, characterized in that the first supply air pipe (1) and the second supply air pipe (2) are disposed side-by-side, in which case air is conducted into them alternately in turns at certain regular intervals.

4. Apparatus according to claim 1 or 2, characterized in that the first supply air pipe (1) and the second supply air pipe (2) are disposed one after the other such that at first in the flow direction of the air is the aforementioned first supply air pipe (1) and after it the aforementioned second supply air pipe (4) is fixed, and in that an openable and adjustable valve is disposed between them, in which case the valve is in the open position when more supply air is desired and in the closed position when less supply air is desired.

5. Apparatus according to any of claims 1-4, characterized in that the first supply air pipe (1) is per se a known supply air pipe, comprising nozzles (3) in one row in the longitudinal direction of the pipe, and in that the nozzles of the second supply air pipe (2) are disposed n a number of longitudinal rows, e.g. at regular intervals on the rim of the pipe.

Drawing