WO1997016684A1

WO1997016684A1 - Process for generating by radiation warm air from transformation of electric energy directly into diffused heat

Info

Publication number: WO1997016684A1
Application number: PCT/IT1996/000054
Authority: WO
Inventors: Aldo Stabile
Original assignee: Cadif S.R.L.
Priority date: 1995-11-03
Filing date: 1996-03-20
Publication date: 1997-05-09
Also published as: ITMI952275A1; AU5119196A; IT1281333B1; ITMI952275A0

Abstract

Process for generation of warm air by radiation from panels comprising conductors made from continuous strips (31) through which electric current passes placed in one or more parallel units inside the chamber (17) of a stove (10) into which cold air enters spontaneously through lower holes (40) and emerges, after heating, through upper holes (41).

Description

Process for generating by radiation warm air from transformation of electric energy directly into diffused heat

A great many processes and means exist for warming environments by generation of heat based essentially on combustion especially of gas, => and on electric resistance

In both cases a thermal chain is set up which conditions thermal efficiency of the installation

In the first case, for example, a combustible gas feeds a burner whose flame transforming into heat the energy from the gas heats the water in I 0 a boiler connected to radiators,

In the second case, for example, electric current circulating in heating elements, heats them so transforming electric energy directly into thermal energy

These heating elements reach very high temperatures even 500°C

1 3 In both cases, however, there will clearly be considerable heat losses along the whole thermal chain especially because of the great difference in temperature between the flame, or electric heating element and ambient temperatures Particularly as regards heating by electricity, there is a double thermal ° jump and a correspondingly double loss of efficiency the one that occurs during heating of the elements and the other that occurs when heat is transferred from the elements to the environment

The result is that, when .compared with the energy available and consumed, very little is in fact distributed 2 5 The inventor of this present application has already disclosed a process for obtaining heat from conversion of electric energy into diffused warmth, by passing current through a continuous conducting body of a thickness expressed in microns and of a section whose ratio between width and thickness is very high

On matching said conducting body, by electrical means of connection 5 and of installation, with a supporting and heat diffusing body, substantially bidimensional, with an approximate ratio of 1 /1 between the surface through which electric current passes and the supporting body, a uniform diffusion of heat is obtained from said body, through which current passes, to the supporting body, and transmission of heat from l o this body to the environment by radiation as soon as the temperature of the supporting body, substantially equal to that of the body through which current passes, exceeds ambient temperature by a few degrees Therefore, with the invented process, in view of the very low thermal jump between the heating element and the environment, and thanks to the fact

1 5 that heat is already diffused when generated, a very great increase in efficiency is obtained from present generators

Subject invention discloses a process for transfer of diffused heat by means of the above process to the atmosphere, the purpose of this being to obtain the positive effects of efficiency, very low thermal inertia, 0 simplicity of generating apparatus and others, even in the many cases where warm air is useful and advisable by greater environmental diffusion, by suitably directing the warmth and other important uses Subject of the invention is a process for generation of warm air, by means of which air is heated by radiation from large heat exchanging surfaces 5 obtained from extended strips of continuous conductors of a thickness measured in microns and of a section having a very high ratio between width and thickness, through which electric current passes Cold air is made to pass against one or more radiating surfaces obtained from extended strips of conductors. _Q Temperature of the continuous conductors is low corresponding to a low thermal jump between the continuous conductors and the environment Temperatures of the continuous conductors are about 100°-150°C Movement of air is spontaneous or else is moved by fans The metal sheets are of anodized aluminium 5 The continuous conductor can be supported by one or more sheets of plastic

The continuous conductor can be held firm inside a panel made of two opposing sheets of anodized aluminium, air being made to pass up 5 against one or more of such panels

In advantageous forms of utilization the radiating panels are placed in one or more parallel units, at a certain distance one from another, in the chamber of a stove This chamber, made of two opposing parallel walls of the stove's casing, o forms lower and upper freely communicating compartments

In the lower and upper areas of the casing, lower and upper holes are made for free passage of air so that cold air spontaneously enters the chamber through the lower holes and leaves through the upper holes having been heated on the way by radiation from the panels 5 The upper holes are made in approximately the upper part of the casing The shape of said casing is parallelepiped

The casing is made from continuous metal sheeting creating two flat parallel faces joined uppermost by a common cylindrical surface that forms the top of the casing 0 At the lower end said faces terminate in two cylindrical surfaces facing in opposite directions and meeting a plate that forms the base of the stove The lower holes are made in the cylindrical surface at the lower end of one face of the casing constituting the front of the stove The casing of the stove may be of metal or of plastic 5 The conductor is made of a strip of copper or other material

Voltage of the current is preferably 220 Volt

The thermal jump between radiating bodies and the environment is roughly 50° - 100°C

The invention offers evident advantages Diffused warmth is transferred to the air by radiation, said diffused heat being obtained by transformation of electric energy, warming the environment both by the warmed air itself and by radiation towards any point of use requiring warm air with minimum thermal jump and maximum diffusing surface, therefore operating at a high level of efficiency by simple and inexpensive means

Characteristics and purposes of the invention will become still clearer from the following example of its execution illustrated by a diagrammatically drawn figure.

Fig.1 . Perspective view of a stove obtained by the process subject of the invention. The stove 10 comprises the casing 1 1 obtained from a piece of metal sheeting 12 curved in the arc of a circle at 1 80 at the top 13 and at 45^c outwards at the lower ends 14 and 15 where it is fixed to the lower plate

1 6 forming an inner chamber 17 of a volume 1 8 below and a volume 19 above

At a substantially intermediate position between the two main parallel walls 20 and 21 of the casing and inside it is a panel 30 made from a continuous strip of copper 31 laid serpentinewise, held firm and flat between two sheets of anodized aluminium 32, 33

At the lower end of the front wall 20 are holes 40 while at the upper end 13 are holes 41 The copper strip 31 has terminals 35 and 36 connected to the main electricity supply by a wire 37

On closing the electric circuit cold air 50 enters spontaneously through the lower holes 40, said air being heated by passing over the surface of the panel 30 and, transformed into warm air 51 leaving through the upper holes 41 The apparatus therefore supplies warmth to the environment by the warm air 51 and by radiation, indicated by the arrows 51 , from the panel 30

Claims

1 Process for generating warm air characterized in that the air is heated by radiation, heat being diffused from large heat exchanging surfaces obtained from extension of strips of 5 continuous conductors (31 ), whose thickness is expressed in microns and whose section shows a very high ratio between width and thickness, through which conductors electric current passes

2 Process as in claim 1 , characterized in that cold air is caused to pass against one or more l o radiating surfaces obtained from extension of strips of conductors (31 )

3 Process as in claim 1 , characterized in that temperature of the continuous conductors (31 ) is low corresponding to a low thermal jump between the continuous conductors and the environment I 5 4 Process as in claim 1 , characterized in that temperature of the continuous conductors (31 ) is in the region of 100° - 150°C

5 Process as in claim 1 , characterized in that movement of air is spontaneous 0 6 Process as in claim 1 , characterized in that air is forced in by fans and the like

7 Process as in claim 1 , characterized in that the continuous conductor (31 ) is supported by one or more metal sheets (32, 33) against which air is caused to pass 5 8 Process as in claim 7, characterized in that the metal sheet (32, 33) is of anodized aluminium 9 Process as in claim 1 , characterized in that the continuous conductor (31 ) is supported by one or more sheets of plastic 0 10 Process as in claim 1 , characterized in that the continuous conductor (31) is held firm inside a panel (30), made from two opposing sheets of anodized aluminium (32, 33), air being caused to pass up against one or more of such panels 1 1 Process as in claim 1 , characterized in that the radiant panels (30) are placed in one or more parallel units at a certain distance one from another inside the chamber (17) of a stove (10) formed of two opposing parallel walls there being 5 made in the lower and upper areas of said chamber respectively, lower holes (40) and upper holes (41 ) through which the air passes freely so that cold air spontaneously enters the chamber by the lower holes and leaves by the upper holes, said air having been heated by radiation from the panels

I O 12 Process as in claim 1 1 , characterized in that the upper holes (41 ) in the stove (10) are made substantially in the upper part (13) of the stove (10)

13 Process as in claim 1 1 , characterized in that the stove is parallelepiped-shaped

1 5 14 Process as in claim 1 1 , characterized in that the stove (1 0)exhιbιts a parallelepiped-shaped casing (1 1 ) made from a continuous piece of metal sheeting (12) forming two flat parallel faces (20, 21 ) joined uppermost by a common cylindrical surface (13) constituting the top of the casing terminating at the bottom

2 0 in cylindrical surfaces facing in opposite directions fixed to a plate (1 6) that forms the base of the stove 15 Process as in claim 14, characterized in that there are holes (40) made on and near the lower cylindrical part (15) of a front face (21 ) of the casιng(1 1 )of the stove (1 0)

2 5 16 Process as in claim 14 characterized in that the casing (1 1 ) of the stove (1 0) is of metal

17 Process as in claim 14, characterized in that the casing (1 1 ) of the stove (1 0) is of plastic

18 Process as in claim 1 ,

30 characterized in that the conductors (31 ) are made of a strip of copper

19 Process as in claim 1 , characterized in that the preferred voltage for the current is 220 Volt

20 Process as in claim 1 , characterized in that the thermal jump between the radiating bodies (30) and the environment is comprised substantially between 50° and 100°C. 21 . Apparatus (10) obtained by the process described in the preceding claims.