WO2008139224A1

WO2008139224A1 - A heating appliance

Info

Publication number: WO2008139224A1
Application number: PCT/GB2008/050343
Authority: WO
Inventors: Saffet Kalender
Original assignee: PITACS Ltd
Current assignee: PITACS Ltd
Priority date: 2007-05-11
Filing date: 2008-05-12
Publication date: 2008-11-20
Anticipated expiration: 2009-11-11
Also published as: GB2454861A; GB0709124D0

Abstract

In the design of radiators it is necessary to make a compromise between providing good heat transfer characteristics and achieving a visually attractive visual style. The problem is addressed by threading heat dissipation blocks (3) onto tubes (1) that carry heating fluid. The elements (3) provide visual appeal and an increased surface area from which heat can be transferred. The blocks (3) are preferably spherical and formed with slots, defining fins between them so as to maximise the surface area. They can be arranged on adjacent tubes in staggered configuration so that the tubes can be more closely spaced than would otherwise be possible. In one design variation, the spherical blocks carry a photoluminescent coating to help to create a feeling of warmth.

Description

[0001] A HEATING APPLIANCE

[0002] This invention relates to a heating appliance comprising a path for hot fluid defined by at least one tubular member and a heat dissipation element attached to the tubular member and designed to provide an increased surface area from which heat can be transferred to the surrounding environment. The invention was conceived for use in so- called "radiators" in water circulation central heating systems. Although this term "radiator" will be used in this specification it will be understood that the majority of heat from such "radiators" is dissipated by convection rather than radiation.

[0003] In the design of radiators, particularly for domestic use, there are conflicting requirements for heat transfer efficiency and for stylish appearance. Conventional finned radiator designs which aim to optimise heat transfer efficiency are not popular because of their lack of visual appeal. This invention is believed to provide a useful technique by which it is possible to manufacture radiators, particularly wall mounted radiators, having good heat transfer characteristics in a variety of attractive visual styles.

[0004] According to the invention there is provided a heating appliance comprising a path for hot fluid defined by at least one tubular member and a heat dissipation element attached to the tubular member and designed to provide an increased surface area from which heat can be transferred to the surrounding environment characterised in that the heat dissipation element fits at least partially around the tubular member.

[0005] The heat dissipation member preferably takes the form of a metal sleeve or block that will slide over the tubular member during assembly in the factory and can then be fixed at a desired position along the tube e.g. with a heat-conducting adhesive or, more preferably, a retaining member such as a circlip. Preferably there are a plurality of such members distributed along the length of the tubular member; and a plurality of tubular members, each carrying additional heat dissipation members. The distribution of the heat dissipation members can be selected to be non-uniform for visual appeal and/or to distribute the heat transfer characteristics in the most effective way.

[0006] The heat dissipation member can be in any desired shape but a generally spherical shape has been found to be effective and attractive. It is preferably formed with slots, defining fins between them so as to maximise the surface area, and it can be manufactured by machining from a solid block of aluminium or an aluminium alloy selected for its efficient heat transfer properties.

[0007] The tubular member or members are preferably of stainless steel to avoid rusting and for visual appeal. They can be of any desired shape, but straight tubes are preferred for ease of assembly with the sliding heat transfer members. Where more than one tube is included, these tubes are preferably generally parallel and the heat transfer members are arranged on them in staggered configuration so that the tubes can be more closely spaced than would be possible without such staggering, thereby maximising heat transfer capability for a given size of appliance.

[0008] It is known that the perceived warming effect of a domestic appliance can be improved by visual stimulus and for this reason it is conventional to employ a lamp as part of electric convector heaters that would not otherwise produce a light output. However, this effect is not so easily achieved with a radiator in a water circulation central heating system because a convenient source of electric power may not be available. The inventor has now discovered that a particularly effective solution to this problem can be achieved by providing, on selected surface parts of such a radiator, a luminescent (preferably photoluminescent) coating.

[0009] Thus, in accordance with a second aspect of this invention, there is provided a heating appliance designed for connection in a water circulation central heating system, carrying a luminescent coating.

[0010] The coating is preferably applied to heat dissipating elements, e.g. fins, projecting from a surface of the appliance and this technique can be particularly visually effective where the heat dissipating elements are sleeves, blocks or other devices fitting around a tubular member.

[0011] The photoluminescent material preferably contains at least one rare-earth metal such as Europium, Gadolinium, Terbium, Samarium or Cerium; and a base material comprising at least one of the following: An Alkaine earth metal Aluminosilicate, an Alkaline rare earth metal aluminate, an Alkaline rare earth metal Aluminosilicate; and a dopant comprised of at least one rare-earth metal.

[0012] The preferred composition is an Alkaline Rare Earth Silicate-aluminate Oxide Europium Doped luminescent material

[0013] One way in which the invention may be performed will now be described by way of example with reference to the accompanying drawings in which: -

[0014] Fig 1 is a front elevation of a heating appliance constructed in accordance with the invention; and

[0015] Fig 2 is an axial cross-section through one of many heat dissipating elements forming part of the appliance of Fig 1 ;

[0016] Referring first to Fig 1, the illustrated heating appliance comprises an array of parallel straight stainless steel tubes 1 welded at their bottom ends to a rectangular- section stainless steel tube 2 and at their top ends to a similar tube 6. The tubes 2 and 6 are provided with wall fixing brackets (not shown). The bottom tube 2 is divided by a separator 2A into a distribution chamber 2B having an inlet 2C and a collection chamber 2D having an outlet 2E. The top tube 6 has no separator and serves to join the top ends of all the tubes 1. [0017] Onto each tube 1 is threaded a number of identical spherical heat distribution members 3 which are distributed at non-uniform spacings along the tube so that there are more towards the top of the appliance. This provides improved heat transfer capacity towards the top of the radiator which tends to be hottest.

[0018] The spheres 3 are staggered on alternate tubes as shown, allowing the tubes to be spaced more closely than would be possible if a non-staggered arrangement were used. In this connection it is to be noted that the axial separation of the tubes is less than the diameter of a spheres" 3.

[0019] One of the heat distribution spheres 3 can be seen in more detail in Fig 2. It is fabricated from a solid block of aluminium alloy of a type selected for its good heat transfer properties. It is machined to form a central bore having a diameter greater than that of the tube 1 by a very small amount, just sufficient to allow for the member 3 to slide along the tube during assembly. As can be seen from Fig 2 the tube 1 has been machined with grooves on its external surface to receive circlips 4 retaining the spheres 3 in their locations as shown in Fig 1. These circlips are received within recesses machined into the top and bottom surfaces of the spheres 3.

[0020] Each aluminium alloy sphere 3 is machined to form its generally spherical shape and grooves 5. The latter define, between them, fins 7 having a large surface area so as to maximise heat transfer into the surrounding medium.

[0021] In use, hot water from a water circulation central heating system enters, through the inlet port 2C, into the distribution chamber 2B from whence it passes into the tubes shown on the left hand side of Fig 1 and rises into the chamber defined by tube 6 at the top of the appliance. From here it flows down the tubes shown on the left hand side of Fig 1 and is collected in chamber 2D and passes to the outlet 2E.

[0022] During passage of the hot water through the tubes, 1 heat is conducted through the stainless steel walls of the tubes and into the aluminium body 3 from where it is distributed into the surrounding air via the large surface area provided by the surfaces of the fins 6.

[0023] The surfaces of the heat transfer spheres 1 carry a coating IA alkaline Rare Earth Silicate-aluminate Oxide Europium Doped luminescent material. This is applied as a powder to the bodies 1 and baked at 180° to provide a permanent photoluminescent coating. This provides a visual effect of warmth and energy, which reinforces the feeling of warmth as perceived by the user. The luminescent material can be selected to emit a red, blue or yellow/green light.

[0024] An appliance manufactured substantially as illustrated has been found to have especially good heat transfer properties as well as a highly attractive appearance. However, it will be appreciated that the embodiment of the invention that has been described is just one example of an unlimited number of variations of design that can be employed within the scope of the invention as defined by the accompanying Claims. For example, the arrangement of Fig 1 could be turned through 90° so that the tubes 1 are horizontal. The shape and distribution of the members 3 could be varied in any desired way to achieve the desired visual effect and heat distribution properties. The members 3 could be held in their desired positions using heat conductive adhesive instead of circlips and they could be fabricated by a casting process instead of by machining.

Claims

[0001] A heating appliance comprising a path for hot fluid defined by at least one tubular member and a heat dissipation element attached to the tubular member and designed to provide an increased surface area from which heat can be transferred to the surrounding environment characterised in that the heat dissipation element fits at least partially around the tubular member.

[0002] A heating appliance according to Claim 1 characterised in that the heat dissipation element is a metal sleeve.

[0003] A heating appliance according to Claim 2 characterised in that an outer surface of the sleeve is profiled to provide a large surface area

[0004] A heating appliance according to Claim 3 characterised in that the sleeve is formed with slots, defining fins between them.

[0005] A heating appliance according to any preceding claim characterised in that the heat dissipation element is defined by a metal block.

[0006] A heating appliance according to any preceding Claim characterised in that the heat dissipation element is generally spherical.

[0007] A heating appliance according to any preceding Claim characterised by a retaining element for locating the heat dissipation element at a desired position along the tubular member.

[0008] A heating appliance according to any preceding Claim characterised by more than one heat dissipation element on the tubular member.

[0009] A heating appliance according to any preceding Claim characterised by more than one tubular member.

[0010] A heating appliance according to Claim 9 characterised in that the tubular members are generally parallel and are connected so that some receive fluid entering from an inlet and others discharge fluid to an outlet.

[0011] A heating appliance according to Claim 9 or 10 characterised in that the heat dissipation elements are arranged on adjacent tubular members in a staggered configuration.

[0012] A heating appliance according to Claim 11 characterised in that the spacing of the tubular members and the sizes of the heat dissipation elements are such that the profiles of the heat dissipation elements overlap when viewed in the direction of the tubular members.

[0013] A heating appliance according to any preceding Claim characterised by a surface coating on the heat dissipation element or elements, the surface coating containing a photoluminescent material.

[0014] A heating appliance according to Claim 13 characterised in that the photolu- minescent material contains at least one rare-earth metal.

[0015] A heating appliance according to Claim 14 in which the rare-earth metal is

Europium, Gadolinium, Terbium, Samarium or Cerium.

[0016] A heating appliance according to Claim 14 characterised in that the photolu- minescent material is formed from a base material comprising at least one of the following: an Alkaine earth metal Aluminosilicate, an Alkaline rare earth metal aluminate, an Alkaline rare earth metal Aluminosilicate; and a dopant comprised of at least one rare-earth metal

[0017] A heating appliance according to Claim 13 characterised in that the surface coating comprises an Alkaline Rare Earth Silicate-aluminate Oxide Europium Doped luminescent material.

[0018] A heating appliance designed for connection in a water circulation central heating system, carrying a luminescent coating.

[0019] A heating appliance according to Claim 18 characterised in that the coating is applied to heat dissipating elements projecting from a surface of the appliance.

[0020] A heating appliance according to Claim 19 characterised in that the heat dissipating elements are sleeves, blocks or other devices fitting around a tubular member for carrying circulating water.

[0021] A heating appliance according to Claim 18, 19 or 20 characterised in that the photoluminescent material preferably contains at least one rare-earth metal; and a base material comprising at least one of the following: an Alkaine earth metal Aluminosilicate, an Alkaline rare earth metal aluminate, an Alkaline rare earth metal Aluminosilicate.