FI117965B - Heat Transfer arrangement - Google Patents

Description

117965 Heat transfer arrangement

Field of the Invention

The invention relates to a heat transfer device for varying the temperature of the interior of a vehicle, comprising at least one heat transfer element if at least one fluid passage for fluid medium flow; at least one pump communicating with said fluid passage for circulating a fluid medium through a heat transfer element; at least one heating / cooling unit for varying the temperature of the fluid medium; a shell surrounding the heat transfer element and having at least one air channel inside the shell; at least one fan for generating a flow of air into said air channel; at least one flow aperture through which the hating air in the air duct is arranged to vent outside the shell; and at least one narrow aperture through which air hating from the air duct to the flow port is arranged to flow.

The invention further relates to a heat transfer element for varying the interior temperature of a vehicle, comprising at least one fluid channel and at least one fluid channel member adapted to transfer heat between the fluid channel and the surrounding air space, the heat transfer element comprising: a casing surrounding a heat transfer element; 20 for conducting air hate of at least one longitudinal air channel from the first end of the heat transfer element to the second end thereof; at least one • V flow port communicating with said air channel to allow at least: **]: at least partial discharge of the hype outside the shell; and at least one narrow aperture disposed between the flow aperture and the air passage, and • · 25 having an air hate flowing through the narrow aperture adapted to hate.

. ···. The invention further relates to a heat transfer method for a vehicle, wherein the heat transfer device comprises at least one heat transfer element, at least one pump, and at least one: ..7 heating / cooling unit, and wherein: * ··· * 30 la liquid medium in the fluid passage in the heat transfer element; · · · ·: influences the temperature of the liquid medium with the heating / cooling unit; forming: *** airflow into the air channel inside the heat transfer element shell; and conducting at least a portion of said air flow through at least one narrow opening in the heat transfer element and further through at least one flow opening communicating with said * 35 closed opening.

117965 y 2

Background of the Invention

Radiators for controlling the passenger compartment temperature of vehicles such as buses typically include a fluid passageway for passing heating fluid 5 through the radiator and lamellae arranged around the fluid passageway to increase the heat transfer surface of the radiator. Flow through the radiator may be provided in either direction only, or the heating system may be connected in a closed loop so that a returning liquid flow is also passed through the radiator. These types of radiators are usually fitted in the bus under the windows 10, in the passenger's foot space. The problem is that the heat in the cold air does not rise enough to heat the wall and window surfaces, which makes the cold wall surface uncomfortable and water vapor can accumulate in the vehicle windows. Raising the temperature of the radiators is not a solution, as hot radiators feel uncomfortable in the passenger's foot area and can even cause injury. In addition, dust and other dirt build up on the surface of a hot coil.

BRIEF DESCRIPTION OF THE INVENTION An object of the present invention is to provide a novel and improved heat transfer arrangement.

The heat transfer device according to the invention is characterized in that the heat transfer element comprises a labyrinth having a plurality of successive and divergent narrow apertures through which the air flowing from the air duct to the flow aperture is adapted to flow, and the narrow apertures of the maze are dimensioned so that | that the flow velocity of the airflow exiting the flow orifice is greater than the flow velocity in the air duct.

The heat transfer element according to the invention is characterized in that the heat transfer element comprises a labyrinth having a plurality of successive narrow openings in different directions.

The heat transfer method of the invention is characterized by passing at least a portion of the air flow through a plurality of successive and non-directional openings in the labyrinth of the heat transfer element, and ·: **: directing the outflow air flow. from the flow opening to the wall surface, wherein: ***: said wall surface is adapted to act as a heat emitting surface.

It is an essential idea of the invention to pass a fluid medium flow through at least one fluid channel in a heat transfer element, a flow through an air channel in the heat transfer element in the longitudinal direction of the element. The heat transfer element further has at least one flow port through which heated or cooled air in the element is allowed to flow out of the space defined by the element shell. The flow port directs the outgoing air flow as desired. The air flow from the air duct to the flow port is arranged to flow through at least one narrow aperture 5 so that the air exiting the flow port has a higher flow rate than the air filing in the air duct. As the flow rate increases, the transfer of heat from the surfaces that restrict said narrow opening to the air flow is enhanced.

The heat transfer element according to the invention may be quite small in external dimensions but nevertheless extremely effective. Its small size makes it easier to fit, for example. vehicle structures. Further, the heat transfer element according to the invention is light, which is an important feature in vehicle designs. The air jet is used to move the heat away from the element. The air jet can then be directed from the 15 flow openings, for example to the wall surface of the vehicle body, whereby the wall warms up and thus acts as a comfortable and high heat-releasing surface. Since the exterior surface of the heat transfer element does not significantly heat up when the interior of the vehicle is heated, passengers will find the element of the invention comfortable. Furthermore, compared to previous radiators assembled from a plurality of lamella plates, for example, the heat transfer element according to the invention is simple in construction, which makes it easier and less expensive to manufacture.

It is an essential idea of a preferred embodiment of the invention that there are lamellae inside the shell of the heat transfer element which add to the surface and form a labyrinth. The airflow flowing to the flow opening is arranged to pass through a series of successive narrow openings ·: ··· in the maze. This increases the flow rate of the airflow through the maze, thereby enhancing the heat transfer between the airflow and the lamellae. Further, the lamellae are arranged so that the labyrinth changes the direction of the air flow, causing turbulence in the flow, which further improves heat transfer.

It is an essential idea of another advantageous embodiment of the invention that, for example, a large number of very small openings are formed in the shell of the heat transfer element through which the air flow is discharged. The openings may be spaced together to form the desired blow pattern.

* · ·]. The essential idea of a third preferred embodiment of the invention is that the size of the flow opening can be adjusted. In this case, the airflow exiting the heat transfer element can be adjusted along the length of the heat transfer element so that just the right amount of airflow is achieved for the desired objects, for example windows. At some points, mere radiation through the element shell is sufficient, whereby the flow openings 5 may even be completely closed at these points. Further, when the heat transfer line is long and limited blowing power is supplied to it, adjusting the outgoing airflow can ensure that sufficient airflow is also achieved through flow openings remote from the air supply point.

It is an essential idea of a fourth preferred embodiment of the invention that the flow opening is a longitudinal elongated lip opening of the heat transfer element. In this case, the outgoing air flow forms a wide air curtain, which can be used e.g. effectively prevent vapor from forming on the vehicle's window surface and reduce draft sensation.

It is an essential idea of a fifth preferred embodiment of the invention that the heat transfer element is an integrated body formed by extrusion in a single step, comprising at least the shell, the lamellae, the fluid passage and the air passage. Making such a profile by extrusion is cost effective. Element structure may not require any separate components. When installing the heater, it is extremely fast and convenient to cut out the elements according to the application and connect them to the liquid and air supply ducts using the extruded profile rod 20.

An essential idea of a sixth preferred embodiment of the invention is that the heat transfer element is extruded in open I *. · 'Form, whereby the extrusion tool may be simpler. In addition, the extrusion process is easier to carry out. A longitudinal hinge member, such as a thinned portion, is formed in the casing of the heat transfer element, · · ·: * ··. which binds the open halves together and which allows the halves to be closed against each other after extrusion.

It is an essential idea of a seventh preferred embodiment of the invention that the heat transfer element comprises a separately manufactured first half and a second half which are connectable to each other; to form a uniform shell. At least one of said halves has an integrated fluid channel. Further, the air channel is bounded by the first and .. * second halves together. Assembling the element from individually manufactured • · ': * 35 rails facilitates extrusion. In addition, halves of different structure and appearance can be formed and combined to produce 5117965 elements of different properties. For example, the number of lamellae and the number and location of fluid channels may vary. Thus, the element may have the advantages of a modular structure.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be explained in more detail in the accompanying drawings, in which Fig. 1 schematically shows a heat transfer device according to the invention, Fig. 2 schematically shows another cross-section of the heat transfer device according to the invention; Figure 5 is a schematic and end view of one half of an element 15 applicable to the structure of Figure 4; Figure 6 is a schematic view of a third heat transfer element of the invention. Figure 7 is a schematic and plan view of a portion of the heat transfer element of Figure 3; Figure 8 is a schematic and plan view of a portion of the invention. Fig. 9 is a schematic and side elevational view of a connection between two heat transfer elements, Fig. 11 is a diagrammatic and side elevational view of a heat transfer element of the invention, Fig. Fig. 12 shows a schematic and top view of a batch of heat transfer elements according to the invention. The heat transfer element according to the invention is in sectional and longitudinal direction.

* ·· * 'In the figures, the invention is illustrated in simplified form.

·: ··: Similar parts are identified by like reference numerals in the figures.

DETAILED DESCRIPTION OF THE INVENTION The heat transfer device shown in Fig. 1 comprises three series-connected heat transfer elements 1a to 1c which together with the heating / cooling unit 35 2, the connecting pipes 3 and the pump 4 form a closed loop. In the loop 6117965, the same flow of liquid medium circulates through each heat transfer element Laic. Typically, the liquid medium is water mixed with the necessary additives, such as corrosion inhibitors, but other suitable media may, of course, be used. Prior to the first heat transfer element 5, the heating / cooling unit 2 is set at the desired temperature of the fluid medium, after which it begins to cycle through the heat transfer elements 1a to 1c. The fluid channels of the heat transfer elements 1a to 1c are interconnected by connecting pipes 3 or alternatively the heat transfer elements 1a to 1c are arranged in succession to one another. The fluid medium is circulated in the heat transfer device by one or more pumps 4. Furthermore, each of the heat transfer elements 1a to 1c has a fan 5a to 5c for supplying the air flows to be generated to the longitudinal air ducts in the heat transfer elements 1a to 1c. In this case, the pressure in the air ducts is higher than the air pressure. The heat transfer elements 1a - 1c are provided with flow openings 15 through which air stream A heated or cooled by the liquid medium can be discharged. In the element 1a of Fig. 1, the flow opening is a longitudinal lip opening, whereby the exiting air flow A is a wide jet. The element 1b is provided with a plurality of substantially point openings, whereby the air currents A discharged from the element 1b are of the form 20 beams. The flow opening of element 1c is closed so that no air flow is discharged from it, but element 1c only heats the environment by heat radiation.

· · ·: Further, the system may be configured so that the fluid medium circulates through channel 45 in a closed circuit. In this case, the control unit 30 controls: 25 valves 46 which, if necessary, allow the • / ·; fluid medium for fluid circulation.

. ** ·. Figure 2 shows an alternative solution in which the heat transfer element 1 comprises two liquid channels, whereby the flow supplied from the pump 4 flows in one direction in one channel and returns to the pump 4 in the opposite direction through the other channel. At the end of the tumbler 1, the first and second fluid ducts are connected, for example, by a ** connection pipe 3. It is clear that, in this case too, several heat transfer elements may be arranged in series. 2, two fans 5a and 5b are fed into the air duct. The fans 5a and 5b are arranged at a distance from the ends of the heat transfer element 1 in order to distribute the airflow as evenly as possible. The number and power of the fans 5 will naturally be dimensioned according to the particular need. In some cases, the required blowing may be achieved by using only one effective blower 5d to direct airflow along the supply channels 6a and 6b to the desired Correspondingly, a centralized fan 5d can be located and additionally effectively insulated so that it does not cause substantial noise, for example in the vehicle's passenger compartment, via a suitable supply duct. of.

The heat transfer element 1 shown in Figure 3 comprises a casing 7 which is substantially airtight except for the flow opening 8 at the top of the element 1. This allows a portion of the airflow supplied to the air channel 9 of the heat transfer element 1 to exit through the flow opening 8 wherein the flow of fluid medium is led. The shell 7 of the heating element 1 acts as a heat radiating surface, so that by varying the size, coloring and surface quality of the shell 7, the thermal power transmitted from the element 1 can be controlled. Preferably, the element 1 is tapered at its top. Further, the upper part of the element 1 is provided with lamellae 11 which are heated by the heat from the fluid passage 10 20. The fins 11 are provided on both sides of the inner surface of the shell 7. The heat is also provided along the shell 7 to the lamellae 11 opposite to the fluid passage 10. Further, the lamellae 11 are arranged so that: they form a narrow labyrinth before the orifice 8 through which the air flowing to the orifice 9 is forced to flow! **: 25 the other in mind. In the labyrinth, the flow velocity of the air increases due to the narrow gaps ·: ···. Increased flow rate enhances heat transfer from lamellae to air. ** ·. flow. Further, when the flow through the outlet 8 has a high velocity, the effect of the outgoing air flow extends a greater distance from the outlet 8, which is advantageous, for example, in the evaporation of vehicle windows. In addition, the amount of air discharged can be kept relatively small for passenger comfort. The size of the outlet 8 ·: **: size B is selected to achieve the desired airflow. Preferably, the lip opening is about 0.5 mm wide. It is, of course, clear that element 1 may include a plurality of flow openings 8 which may additionally be directed in different directions.

* *] The heat transfer element 1 shown in Fig. 3 is preferably manufactured by extrusion of a metal such as aluminum alloy. In this case: '00'.

: 8 117965 can be pre-extruded with a rod having the desired cross section profile and only when cutting the heat transfer device cut off the necessary sections of such a profile bar.

Fig. 4 shows another constructional variant of the heat transfer element 1. In this case, the element 1 consists of two pieces, namely the first half 1a and the second half 1b, which are manufactured separately, for example by extrusion. The manufacture of such halves is technically easier than the unitary structure shown in Figure 3. In addition, extrusion tools can be up to 10 times more simple. The first half 1a comprises a wedge-shaped slot 12 at the bottom of the shell 7, into which the wedge-shaped connecting surface 13 at the bottom of the second half 1b can be tightly inserted when the element 1 is assembled. The joint may further be secured by welding, brazing, gluing or any other suitable means. The joint may also be a compression joint or a form-locked joint. Further, the upper ends of the half-strips 1a and 1b can be fixed to each other at predetermined intervals, for example by means of screws. Preferably, there is a good contact surface between the halves 1a and 1b so that heat is conducted and equilibrated effectively between the halves. The element 1 formed from the halves 1a and 1b is substantially in accordance with the unitary element shown in Fig. 3. The element 1 is mounted to a heated space such as a driving 20, a cabin wall or a similar mounting surface, for example by an integral mounting part 22 integrated on the outer surface of the second half 1b, wherein the second half 1b is on the mounting surface and the first half 1a forms the visible surface.

Figure 5 shows a half 1c which can be attached to a half 1b instead of the half half 1a shown in Figure 4. Such a modular structure allows versatile modification of element 1. Half 1c comprises another fluid ···. a duct 15 in which a liquid medium return flow can be conducted. The liquid medium flowing in the second fluid channel 15 enhances the transmission of thermal radiation .. from the half 1c. Further, the outer surface of the hemisphere 1c may have protrusions 16 which enhance the scattering of the heat radiation into the environment.

Fig. 6 shows another possibility for manufacturing the *: **: heat transfer element 1 according to the invention. The element 1 is extruded in an open configuration, wherein the sides 17a and 17b of the element 1 are spaced apart at their upper ends. The sides 17a and 17b are connected at the lower end of the element 1 by a hinge member 18. The hinge member 18 may in its simplest form be a thinned portion which allows the flanks 17a and 17b to be bent around the hinge member 18 against one another. Such a construction facilitates fabrication.

Fig. 7 is a top view of an element 1 according to the invention. As can be seen, the flow opening 8 in this case is a longitudinal elongated opening of the element 1, whereby the air flow formed by it is a relatively thin but wide air curtain. A similar effect is also achieved by using several successive and parallel elongated flow openings.

Fig. 8 is a top view of an element 1 according to the invention. In this case, there are several flow openings 8 and are spaced apart. The flow of air discharged from the point flow openings 8 forms a beam-like jet. By influencing the number and size of the flow openings 8, the properties of the element 1 can be arranged as desired.

Figure 9 shows part of the upper end of the heat transfer element 1 according to the invention. The element comprises an adjusting member 19, such as an adjusting screw, for adjusting the size B of the flow opening 8. In this case, the adjusting screw is adapted to bend the right cover plate 20 with respect to the left chamber plate 21. If necessary, the flow opening 8 can be completely closed at desired positions 20 by means of the adjusting member 19. Further, the adjustment of the flow opening 8 may in some cases be made by bending the cover plates 20 and 21 relative to each other so that they remain permanently in the desired position. It is also possible to arrange the flow aperture control by means of an actuator which: * · \ · is controlled by the heat exchanger control unit 30. Such control unit 30 can centrally control the flow size of all elements included in the heat exchanger * * ·: ··: blowing power and temperature of the fluid flow.

. ···. Fig. 10 shows one way of interconnecting the heat transfer elements of the invention. A seal 23, for example a sealing strip, is provided between the first element 1a and the second element 1b. Further, the fluid channels 10 of the elements 1a and 1b are interconnected by an adapter tube 24 sealing against the inner surface of the fluid channels.

*: ··: The heat transfer element shown in Fig. 11 does not comprise a maze, but a large number of small diameter openings are formed in the shell 7.

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ducts 40 through which air flow is led from the air duct 9 to the openings 8 in the outer surface of the casing 7 35. In the narrow openings 40, the flow rate increases, thereby increasing heat transfer from the heated or cooled casing 7 of the fluid duct 10. Further, the length of the openings 40 is dimensioned to provide the necessary heat transfer. The apertures 40 typically have a diameter of less than 1 mm, preferably less than 0.5 mm. Such apertures are relatively easy and inexpensive to make by beam machining methods, such as laser, after the preparation of the blank. In this case, the blank is very simple to manufacture, for example by extruding. The adjacent openings 40 need not be parallel, but the openings 40 may be oriented as desired.

Figure 12 shows that the locations of the openings 40 can be arranged to form a desired blow pattern. The apertures 40 may be provided 10 in a linear manner 41, wherein the resulting blow pattern is curvilinear, or alternatively, the apertures 40 may be provided in delimited areas 42, wherein the resulting blow pattern is dot-like. On the other hand, the casing 7 may be laser-machined with a longitudinal, very narrow aperture 43 forming a curved blowing pattern.

The drawings and the related description are intended only to illustrate the idea of the invention. The details of the invention may vary within the scope of the claims.

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Claims (13)

A material transfer device for changing the temperature within a vehicle, comprising: at least one heat transfer element (1, 1a-1c) having at least one liquid channel (10, 15) for the flow of a liquid medium; eating at least one pump (4) which communicates with said fluid channel (10, 15) for circulating the liquid medium through the heat transfer element (1,1a-1c); at least one heating / cooling unit (2) for changing the temperature of the liquid medium; a sheath (7) surrounding the heat transfer element (1, 1a-1c) and within which sheath (7) there is at least one air duct (9); at least one fan (5a-5d) for forming an air stream to said air duct (9); At least one outlet port (8) through which the air flowing in the air duct (9) is arranged to discharge outside the manifold (7); and at least one narrow opening, through which the air flowing from the air duct (9) to the outlet opening (8) is arranged to flow, characterized in that the heat transfer element (1, 1a-1c) comprises a maze with several consecutive and different openings. through which the air • flowing from the air duct (9) to the outlet opening (8) is arranged: * · *: to flow, and that the narrow openings of the maze are dimensioned so that the flow velocity of the air flow which is discharged from the discharge port. ···. (8) is greater than the flow rate in the air duct (9). • » 2. A heat transfer device according to claim 1, characterized in that the maze is formed by slats (11) in the inner surface of the sheath (7). ♦ · 3. A heat transfer device according to claim 1 or 2, characterized in that the heat transfer element (1, 1a-1c) is an elongated ·: ··: piece, and that the flow opening (8) is a elongated gap in heat transfer: ***. longitudinal direction of the ring element (1,1a-1c). * · · .. * 4. Heat transfer device according to any of the preceding claims, characterized in that the size of the outlet opening (8) "**: 35 can be regulated. 15 1 1 7965 A heat transfer device according to any of the preceding patent claims, characterized in that the heat transfer device comprises several heat transfer elements (1, 1a-1c) connected in series, and that the heat transfer elements (1, 1a-1c) are connected to a common fan (5). . 5 A heat transfer element for changing the temperature inside a vehicle, said heat transfer element comprising at least one fluid channel (10, 15) and at least one member which is in communication with the fluid channel (10, 15), which means is arranged to transfer heat between the fluid channel (10, 15) and the air space surrounding it, and which heat transfer element (1, 10 1a-1c) comprises: a jacket (7) which surrounds the heat transfer element; at least one longitudinal air duct (9) for conducting an air flow from the first end of the heat transfer element (1, 1a-1c) to its second end; at least one outlet port (8) which interferes with said air duct (9) allowing at least partial discharge of the air stream outside the manifold (7); and at least one narrow orifice disposed between the outlet orifice (8) and the air duct (9), through which the orifice of the discharge air stream is arranged to flow, characterized in that the heat transfer element (1, 1a-1c) comprises a maze with several consecutive and unequal narrow congestions. 7. A heat transfer element according to claim 6, characterized in that the maze is formed by slats (11) in the inner surface of the sheath (7). I · · • V 8. A heat transfer element according to claim 6 or 7, characterized in that the heat transfer element (1, 1a-1c) is an elongated portion: and the outlet port (8) is an elongated gap in the heat transfer element. **. the longitudinal direction of the guide element (1,1a-1c). 9. Heat transfer elements according to any of the preceding patents: ·. claims 6-8, characterized in that the size of the outlet opening (8) can be regulated. • * A heat transfer element according to any of the preceding patents: claims 6-9, characterized in that the heat transfer element (1,1 a-1 c) is a unitary piece formed by extrusion. ./ 11. Heat transfer element according to claim 10, characterized by *. Characterized in that the heat transfer element (1, 1a-1c) comprises a first side (17a) and a second side (17b), and that the sides (17a, 17b) are joined at a 16 1 7965 edge by a longitudinal hinge member (18). ), wherein the sides (17a, 17b) can be pivoted in relation to said hinge means (18). A heat transfer element according to any one of the preceding claims 6-9, characterized in that the heat transfer element (1, 1a-1c) comprises a first half (1a) and a second half (1b), at least one half (1a, 1b). comprises a fluid channel (10, 15), and the halves (1a, 1b) comprise at least one fastener (12) for joining them together. A heat transfer method for a vehicle in which a heat transfer device comprising at least one heat transfer element (1, 1a-1c), at least one pump (4) and at least one heating / cooling unit (2) is used. and in which method: a liquid medium is circulated by means of a pump (4) in the liquid channel (10, 15) in the heat transfer element (1, 1a-1c); the temperature of the liquid medium is affected by the heating / cooling unit (2); an air stream is formed into the air duct (9) within the jacket (7) of the heat transfer element (1, 1a-1c); and at least a portion of said air stream is passed through at least one narrow opening in the heat transfer element (1, 1a-1c) and further via the eating-at least one outlet opening (8) which starts in connection with said narrow opening outwardly inside the manifold (7), k characterized by the fact that • φ · at least a portion of the air stream is passed through several of each other: ·! The discharging air stream is directed from the outlet opening (8) *: ··: towards a wall surface, said wall surface being arranged to act as a surface; ***; which radiates heat. · · · · · · · · ··· · · · ····· · · · ···· · · · · ···