WO1995033968A1

WO1995033968A1 - Fluid heating system

Info

Publication number: WO1995033968A1
Application number: PCT/CA1995/000331
Authority: WO
Inventors: Pierre Lambert
Original assignee: Lambert, Patrick
Priority date: 1994-06-06
Filing date: 1995-06-06
Publication date: 1995-12-14
Also published as: CA2125229A1; AU2559095A

Abstract

The present invention relates to a fluid heating system (10) to be used in connection with a boiler or the like and more particularly relates to a heat exchanger type device which can supply a large quantity of hot fluid such as water without the necessity of oversizing the boiler and with most effective heating performance. The heating system (10) comprises a primary fluid circuit (16) connected to the boiler and a secondary fluid circuit (18) supplying the necessary hot fluid typically for domestic use. The secondary fluid circuit (18) comprises a plurality of coiled tubes (38) of small diameter which are immersed in the fluid of the primary circuit (16) which is circulated in a tank (10). The coils of the coiled tubes (38) of the secondary circuit (18) are slightly spaced apart one from another thereby allowing for an optimum heat exchange between the fluids of the primary and secondary circuits (16, 18). The fluid to be heated which circulates in the secondary circuit (18) is preferably city water. An injection plate (24) is provided at the entry of the fluid of the primary circuit (16) in the tank (10) so as to distribute the heating fluid substantially uniformly in the tank (10) and which causes some turbulence in order that all of the coiled tubes (38) of the secondary circuit (18) are heated by the primary fluid in a substantially uniform manner and also in order to increase the heat exchange.

Description

FLUID HEATING SYSTEM

TECHNICAL FIELD

The present invention relates to a fluid heating system and, more particularly, to a high efficiency fluid heating system in the form of a heat exchanger having a plurality of coils immersed in a heating fluid and through which the fluid to be heated is circulated with the fluid to be heated and the heating fluid flowing in a substantially same direction.

BACKGROUND ART

Numerous systems have been developed for heating fluids such as water. When high volumes of hot water are required within a short period of time, while at other times smaller volumes are required, such as in apartment buildings or health clubs, the necessary equipments to achieve such heating needs must be sized so as to be able to supply hot water at a high and uniform temperature during the peak periods. Systems of this kind have previously been used and comprise generally a boiler and a heat exchanger, whereby heat in the form of hot water or oil is caused to circulate through a first piping system extending from the boiler to the heat exchanger so as to heat a fluid circulating in a second piping system.

Such heating requirements are also necessary in restaurants and other establishments employing automatic equipments having intermittent demands for hot water. This caused a major problem since it was necessary to provide the system with a boiler which is used at full capacity only intermittently.

An example of a similar system is disclosed in United States Patent No. 2,781,174

(Smith) in which a dual system for heating water is presented. This system comprises a boiler and a water heater.

United States Patents No. 361,803

(Andrews) and No. 3,341,122 (Whittell) disclose a water heater having two circuits in which the secondary circuit is generally arranged with a continuous coil of pipes through which water is permitted to pass for heating.

United States Patent No. 1,617,513 (Hartmann) discloses an apparatus for super-heating steam by means of a high pressure medium. This patent shows an incoming water pipe which is subdivided into a plurality of coils in the secondary circuit. However, since there is no means to adequately force the heat exchange between the primary and the secondary circuits, heat exchange in such a system is not appropriate.

United States Patent No. 4,347,972 (Hillerstroman et al. ) discloses an apparatus for producing hot water. This system also comprises a primary and a secondary circuit. However, the primary circuit only comprises a single coil pipe in which the exchange is possible.

United States Patent No. 4,084,546 (Schneebergen et al) shows a heat exchanger formed by two cylindrical shells defining annular chambers. This system uses mainly steam for heating the secondary circuit. Therefore, there is no particular problem with appropriate heat exchange.

Those systems are cumbersome because a large heat exchanger and a high capacity boiler are necessary for appropriate heat exchange between the primary and the secondary circuits since, as mentioned hereinabove, the heat exchange is not optimum and the boiler must be sized to be able to produce heat to meet short term demand.

Canadian Patent Application No. 2,028,693 which was laid-open on April 27, 1992 in the name of Pierre Lambert discloses a fluid heating system to be used in connection with a boiler or the like and which incorporates a heat exchange system which comprises a primary fluid circuit connected to the boiler and a secondary fluid circuit supplying the necessary heated fluid. The secondary fluid circuit comprises a plurality of coiled tubes through which the fluid to be heated is circulated with the coiled tubes being submerged in a tank through which the heating fluid coming from the boiler is circulated for allowing heat to be exchanged from the primary system's tank fluid to the fluid circulating in the coiled tubes of the primary circuit. Furthermore, a turbulence means in the form of a perforated pipe was added to the first circuit to increase such heat exchange. As opposed to the heating system of

Canadian Patent Application No. 2,028,693, it is noted that prior fluid heating systems comprised a primary circuit made of coiled tubes containing the heating fluid which would heat by heat exchange the fluid to be heated contained in the tank of the secondary circuit, whereby the heat transfer would occur from the coiled tubes to the tank.

Also, prior heating systems use coiled tubes which have large radii and in which the coils are in contact successively one with another.

DISCLOSURE OF INVENTION

It is therefore an aim of the present invention to provide an improved fluid heating system in which the fluid to be heated is circulated in a series of coiled tubes immersed in the heating fluid.

It is also an aim of the present invention to provide a fluid heating system which is very efficient and thus economical.

It is a further aim of the present invention to provide a fluid heating system in which the fluid to be heated and the heating fluid flow in a substantially same general direction.

It is a still further aim of the present invention to provide a fluid heating system in which the heating fluid is itself heated upstream of the heat exchanger by a heating source, such as a boiler, having a smaller heat output than that required with conventional fluid heaters.

It is a still further aim of the present invention to provide a fluid heating system in which the fluid can be rapidly heated. It is still a further aim of the present invention to provide a fluid heating system connected to a boiler or the like which will supply hot fluid for a considerable time after the boiler has been shut down.

It is a still further aim of the present invention is to provide a fluid heating system in the form of an energy accumulation system connected to a boiler or the like supplying hot fluid without the necessity of oversizing the boiler to meet short term demand and with effective heating performances.

It is a still further aim of the present invention to provide a heating system in which maximum efficiency is obtained when the fluid to be heated is water.

Therefore, in accordance with the present invention, there is provided a fluid heating device comprising a container means, primary fluid circuit means having first inlet and outlet means, secondary fluid circuit means having second inlet and outlet means, a heating fluid and a fluid to be heated circulating respectively in said primary and secondary fluid circuit means, said secondary fluid circuit means comprising at least one coiled tubing means extending in said container means between said second inlet and outlet means and being substantially immersed in said heating fluid, said heating fluid being supplied to and withdrawn from said container means respectively by said first inlet and outlet means with said heating flu-ι.ά and said fluid to be heated flowing substantially in a co-current manner, flow distribution means being provided for substantially uniformly distributing said heating fluid on said coiled tubing means while causing turbulence in said heating fluid so that said heating fluid substantially uniformly heats said coiled tubing means thereby improving the heat exchange between said primary and secondary fluid circuit means.

Also in accordance with the present invention, there is provided a fluid heating device comprising a container means, primary fluid circuit means having first inlet and outlet means, secondary fluid circuit means having second inlet and outlet means, a heating fluid and a fluid to be heated circulating respectively in said primary and secondary fluid circuit means, said secondary fluid circuit means comprising a series of coiled tubing means extending in a spaced apart and substantially parallel relationship in said container means between said second inlet and outlet means and being substantially immersed in said heating fluid, said heating fluid being supplied to and withdrawn from said tank means respectively by said first inlet and outlet means with said heating fluid flowing substantially co-current with said fluid to be heated, each of said coiled tubing means having slightly spaced apart coils and defining a substantially limited gyratory radius in order that said fluid to be heated flows therein with a substantially high centrifugal acceleration such that an efficiency of said fluid heating device is above 100%.

Further in accordance with the present invention, there is provided a method of heating a fluid comprising the steps of: a) submitting the fluid to a sufficient centrifugal force while substantially avoiding turbulence in the fluid; and

b) supplying to the fluid an energy input sufficient so as to release from the fluid potential energy thereof, whereby the fluid at least partly heats itself.

Still further in accordance with the present invention, there is provided a method of heating a fluid comprising the steps of:

a) submitting the fluid to a sufficient centrifugal force while substantially avoiding turbulence in the fluid; and

b) supplying to the fluid an energy input sufficient so as to convert potential energy of said fluid into thermal energy.

BRIEF DESCRIPTION OF THE DRAWINGS

Having thus generally described the nature of the invention, reference will now be made to the accompanying drawings, showing by way of illustration a preferred embodiment thereof, and in which:

Fig. 1 is a schematic isometric view of a fluid heating device in accordance with the present invention incorporating a heat exchanger;

Fig. 2 is a schematic plan view of an injection plate of the fluid heating device of Fig. 1; Fig. 3 is a schematic plan view of a suction plate of the fluid heating device of Fig. 1;

Fig. 4 is a schematic elevational view partly broken away of a fluid heating device similar to Fig. 1 and showing in more details some of the coiled tubes thereof, but wherein there is provided directly in the heat exchanger, as opposed to the heating device of Fig. 1, a heating device for the heating fluid; and

Fig. 5 is a schematic cross-sectional view of a modified tubing used in the coiled tubes of the present heating device.

MODES FOR CARRYING OUT THE INVENTION

In accordance with the present invention, Figure 1 is a schematic isometric view of a fluid heating device D in accordance with the present invention in the form of a heat exchanger. The fluid heating device D comprises a tank 10 in the form of a cylindrical shell having a rounded upper end 12 and a lower end 14 for closing the cylindrical shell or side walls of the tank 10 with the lower end 14 including a convex annular outer wall 15 and a concave dome-shaped inner wall 17. The fluid heating system is of the heat exchanger type and comprises a primary circuit 16 and a secondary circuit 18 through which are respectively circulated the heating fluid and the fluid to be heated. The heating fluid which will circulate generally in bulk in the tank 10 is fed thereto by way of a first inlet pipe 20 which extends through the lower end 14 of the tank 10 for supplying the heating fluid in the tank 10 downwardly towards the lower end 14 so that the heating fluid is substantially evenly distributed throughout the horizontal area of the lower end 14 of the tank, as shown by arrows 22. The heating fluid circulated in the primary circuit 16 is, upstream of the first inlet pipe 20, heated by a boiler (not shown) or other heat generating means.

Once the heating fluid of the primary circuit 16 has exited the first inlet pipe 20 at the lower end 14 of the tank 10, it is redirected upwardly (arrows 22) by the lower end 14 towards an injection plate 24 which extends transversely to the tank 10 and which defines a series of openings 26, as best seen in Figure 2. The downwardly extending end of the first inlet pipe 20 coupled with the configuration of the lower end 14 and with the hole distribution in the injection plate 24 ensure that the heating fluid of the primary circuit 16 is transversely distributed throughout the tank 10. The injection plate 24 further ensures that the heating fluid of the primary circuit 16 circulates above the injection plate 24 with turbulence. The heating fluid of the primary circuit 16 flows upwardly in the tank 10 right up to a suction plate 28 which defines a series of generally uniformly radially distributed openings 30, as best seen in Figure 3. The heating fluid of the primary circuit 16 exits the tank 10 through a first outlet pipe 32 extending through the upper end 12 of the tank 10. The heating fluid exiting the tank 10 returns through conduits (not shown) to the boiler, or the like, so that it can be reheated prior to returning to the tank 10 through the first inlet pipe 20, whereby the primary circuit 16 is normally a closed circuit. It is noted that the tank 10 is provided with standard fittings, such as a safety valve 34 provided at the upper end 12 thereof and a drain plug 36 provided at the lower end 14 of the tank 10. The tank 10 is supported by legs 37.

It is further noted that, for illustration purposes, only some of the openings 26 and 30 defined respectively in the injection plate 24 and in the suction plate 28 are shown in Figure 1 and, for a complete illustration of these openings 26 and 28, reference is made respectively to Figures 2 and 3.

The secondary circuit 18 comprises a plurality of coiled tubes 38 which extend parallelly and vertically throughout the tank 10 and which receive the fluid to be heated by the primary circuit, such as cold water from the public waterworks system, with only one such coiled tube 38 being shown in Figure 1 for illustration purposes. Lower ends 40 of the coiled tubes 38 are all connected to a lower end 42 of a second inlet pipe 44 which extends longitudinally through the tank 10 from the upper end 12 thereof so as to receive therein the fluid to be heated for distribution at the lower end 42 thereof to the lower ends 40 of the various coiled tubes 38. The fluid to be heated then circulates upwardly through the coiled tubes 38 right up to upper ends 46 of the coiled tubes 38 which are all connected to a lower end 47 of a second outlet pipe 48. The lower end 42 of the second inlet pipe 44 can take the form of a manifold to which the lower ends 40 of the coiled tubes 38 can be easily connected. Similarly, the lower end 47 of the second outlet pipe 48 can also take the form of a manifold adapted for connection to the upper ends 46 of the coiled tubes 38.

Figure 4 illustrates a variant 10 ' of the tank 10 of Figure 1 with the tank 10' further including at its bottom heating elements 49 in replacement of or in addition to the boiler which must be used in the fluid heating device D of Figure 1. Figure 4 better illustrates the secondary circuit 18 including the coiled tubes 38, the lower ends 40 of the coiled tubes 38 in fluid communication with the lower end 42 of the second inlet pipe 44, and the upper ends 46 of the coiled tubes 38 in fluid communication with the lower end 47 of the second outlet pipe 48.

Accordingly, the coiled tubes 38 of the secondary circuit 18 are in the illustrated embodiment completely immersed or submerged in the heating fluid of the primary circuit 16 which circulates generally in the tank 10.

An expansion area 50 is provided at the upper end 12 of the tank 10, above the suction plate 28, in order to allow room for any dissolved air liberated in the tank 10 by the heating fluid, e.g. water, of the primary circuit 16. An air vent (not shown) is provided at the upper end 12 of the tank 10 to allow for the evacuation from the tank 10 of any excess air. The size and shape of the tank 10 as well as the number of coiled tubes 38 depend on the quantity of hot water necessary for a specific application. The material used for the manufacture of the tank 10 should be chosen while taking into account the temperature and pressure involved. Thus, for different system capacities and applications, the size and the number of coiled tubes 38 will vary.

A supporting structure 52 provided in the tank 10 for supporting the coiled tubes 38 comprises a central column 54 and a series of vertically spaced apart and horizontally extending X-shaped frameworks 56 which are centrally connected to the central column 54 and which extend between the coils of the coiled tubes 38 for the support thereof in the tank 10. In Figure 1, the supporting structure 52 is shown in a substantially isometric way for better viewing of its shape.

With reference to Figure 2, the openings

26 of the injection plate 24 are grouped in a series of staggered rows with each grouping including, in the illustrated embodiment, five staggered openings 26. Each grouping of five openings 26 is located oppositely below a respective coiled tube 38, as it is illustrated in Figure 1 for one such grouping and one such coiled tube 38. Accordingly, with the injection plate 24 of Figure 2, the secondary circuit 18 comprises eleven coiled tubes 38 which extend vertically above the eleven groupings of five openings 26 shown in the injection plate 24 of Figure 2. The injection plate 24 and the distribution of the openings 26 thereof will ensure a better distribution of the heating fluid of the primary circuit 16 on the various coiled tubes 38 of the secondary circuit 18.

The suction plate 28 withdraws the heating fluid in a substantially homogeneous manner from the portion of the tank 10 located below the suction plate 28 in order to ensure that the heating fluid of the primary circuit 16 is removed uniformly from the whole area ;f the tank 10, and not only from a central portion hereof.

With the second inlet pipe 44 and second outlet pipe 48 extending in a substantially diametrically opposed manner in the tank 10, the length of the coiled tubes 38 will all be substantially identical as, for instance, a coiled tube 38 located, as in Figure 1, close to the second inlet pipe 44 will include a short lower end 40 but a long upper end 46. This is well seen in the embodiment of Figure 4 which illustrates four coiled tubes 38 distributed within the tank 10' and connected to the second inlet and outlet pipes 44 and 48, respectively.

The turbulence created in the heating fluid of the primary circuit 16 by way of the injection plate 24 improves the heat exchange between the primary and secondary circuits 16 and 18 thereby considerably reducing the size of the heat exchanger since the temperature of the water within the tank 10 is substantially uniform. The turbulence caused by the injection plate 24 will create a high velocity of heating fluid of the primary circuit 16 from the lower portion of the tank 10 which will allow for the heating fluid to replace fluid in the vicinity of the coiled tubes 38 which has been cooled by the transfer of heat between the primary and secondary circuits. The cooled fluid of the primary circuit 16 then escapes upwardly at the upper end 12 of the tank 10. Due to the aforementioned turbulence, the colder fluid of the primary circuit 16 which would normally move down due to its relatively greater density, will be forced upwards through the tank 10. By doing so, an optimum heat exchange is achieved between the primary and secondary circuits 16 and 18. The turbulence in the heating fluid of the primary circuits 16 also causes the air to separate from the water when water is used as a heating fluid, with the liberated air being vented from the tank 10.

Using the fluid heating device D of Figure 1, the following results have been obtained. The tank 10 has substantially a diameter of 24 inches and a straight height of 68 inches with an additional 6 inches at the lower end 14 thereof and additional 4 inches at the upper end 12 of the tank 10. There are twenty (20) coiled tubes 38 each having an inside diameter of 0.3125 inch. The outer diameter of each coiled tube 38 is 4.375 inches and the thickness of the copper tubing is 0.375 inch, whereby the mean diameter of the coiled tube 38 is 4 inches. There are 100 gallons per minute (GPM) circulating in the twenty coiled tubes 38, that is 454.6 liters per minute. Thus, there is five gallons per minute (or 20 liters) circulating in each coiled tube 38. The cross-sectional opening in the coiled tube 38 is 0.4948315 cm². The length of each coiled tube 38 is one hundred (100) feet and the fluid to be heated circulates in a coiled tube 38 in 3.981293 seconds. The fluid to be heated therefore circulates in the coiled tube 38 at a speed of 27.560896 km/hr. The centrifugal acceleration in the coiled tube 38 is 1153.7665 meter/sec², or 117.61127G.

Therefore, with reference to Figure 1, 100

GPM are introduced in the second inlet pipe 44 for distribution by way of the manifold provided at the lower end 42 to the various coiled tubes 38. The tests having been made with city water, the water introduced in the secondary circuit 18 has a temperature of 55°F. With respect to the primary circuit 16, the heating fluid which is water in the present example is supplied to the tank 10 by the first inlet pipe 20 at a rate of 45 GPM and at a temperature of 160°F (12 psi).

Under these conditions, the heated water exiting at a flow of 100 GPM from the secondary circuit 18 at the second outlet pipe 48 thereof had a temperature of 145°F with the heating fluid of the primary circuit 16 exiting the tank 10 at the first outlet pipe 32 with a temperature of 145°F. Accordingly, the heating water of the primary circuit 16 flowing at 45 GPM underwent a temperature loss of 15°F, whereas the heated water of the secondary circuit 18 flowing at a 100 GPM benefited from a 90°F increase. It is believed that part of the increase in temperature of the water circulated in the secondary circuit 18 results from a heat transfer with the water of the primary circuit 16 and furthermore that an additional increase in the temperature of the water contained in the secondary circuit 18 results from the high speed and molecular agitation of the water circulated in the secondary circuit 18 in view of the small curvature/gyratory radius of the coils of the coiled tube 38.

It is noted that the fluids circulating in the secondary circuit 18 can be water, oil, glycol or any other appropriate fluid, although the optimum output has been obtained with water, either in a liquid or vapor state. It is further noted that it is also possible to cool the fluid of the secondary circuit 18 if the primary circuit 16 is connected to a cooling unit.

Again, the lower end 14 of the tank 10 ensures that the stream of heating fluid flowing downwardly from the first inlet pipe 20 is redirected by the lower end 14 upwardly in the tank 10 in a substantially uniform fluid diffusion on a surface perpendicular to the axis of the tank 10.

It is also noted that the transverse dimensions of the X-shaped groupings of the openings 26 of the injection plate 24 are substantially identical to the diameter of the coiled tubes 38 located thereabove. The injection plate 24 forces the heating fluid of the primary circuit in the tank 10 at high speed, such as a water hose nozzle, so as to produce turbulence in the tank 10 thereby ensuring a stirring of the heating fluid of the primary circuit 16 around and within the coiled tubes 38 of the secondary circuit 18 and thus a uniform temperature about the coiled tubes 38. This ensures an optimal gain of energy in the fluid of the secondary circuit 18.

With respect to the suction plate 28 best illustrated in Figure 3, the openings 30 are defined radially with respect to a central axis of the suction plate 28 thereby ensuring a uniform withdrawal of the fluid of the primary circuit 16 from the tank 10.

The coiled tubes 38 are characterized by a small tubing diameter as well as a small gyratory radius. A small tubing diameter is necessary in order to maximize the exchange surface per unit of volume of water, or other fluid, circulated in the secondary circuit 18.

The primary circuit 18 has a minimum pressure of 12 psi and a maximal pressure governed by safety factors concerning the various equipment parts of the system. The minimum temperature at the entry of the primary circuit 16 is 160°F when using copper coiled tubes 38. If another material should be used for the coiled tubes 38, the minimum temperature of the primary fluid has to be readjusted in order to obtain a specific heat coefficient superior to 0.302 W/°C. At lower temperatures, the reaction within the heating device D is not as significant and the fluid heating device D of the present invention acts more as a standard heat exchanger.

From the above example and test results, it is easily understood that the efficiency is well above 100%. As such results have been obtained when standard city water has been used as the fluid circulating in the secondary circuit 18, it is believed that the water used as the secondary fluid is characterized by properties which, under certain conditions, causes the water to release energy to the system. The water used as a secondary fluid is that of the city waterworks and thus issues from rivers, lakes and other bodies of water. As it is well known, such bodies of water contain approximately 0.015% of deuterium, that is one gallon of deuterium per 6,500 gallons of ordinary water. As it is also well known, the fusion of two atoms of deuterium produces a large quantity of energy without producing any harmful radiation. Cold fusion has been previously obtained in laboratories although none of the tests realized in such laboratories used a principle resembling, from close or afar, the process embodied in the above heating fluid system D. From the test results set forth hereinabove, the temperature differential in the primary circuit 16 is 15° with a flow of 45 GPM, whereas the water in the secondary circuit 18 is characterized by a positive temperature differential of 90°F with a flow of 100 GPM. This will indicate an efficiency of 1330% (i.e. in the primary: 45 GPM x 10 lb. water/min. x 15°F = 6,750 BTU; and in the secondary: 100 GPM x 10 lb. water/min. x 90°F = 90,000 BTU) .

It is believed that the combined effect of the large speed of the secondary fluid with the small gyratory diameter of the coiled tubes 38 produces a centrifugal force on the secondary fluid within the coiled tubes 38 which, it is believed, acts on the molecules of the water in the secondary circuit 18 in such a way as to give these molecules a homogeneous distribution and a certain positioning in the coiled tubes 38 which possibly catalyse an energy producing reaction in the water of the secondary circuit 18, such as a cold fusion reaction. Potential energy in the water is believed to be released or converted into thermal energy.

As opposed to standard heat exchangers, it is again noted that the fluid of the secondary circuit 18 circulates in the coiled tubes 38 and, furthermore, circulates co-current with the fluid of the primary circuit 16, that is from the bottom towards the top of the tank 10 as does the heating fluid of the primary circuit 16. The displacement of the heated and heating fluid; 5 co-current even if the tank is oriented different

The second inlet pipe 44 and the second outlet pipe 48 of the secondary circuit 18 are made of copper having a two-inch diameter and are used for respectively distributing and collecting the secondary fluid from the secondary circuit 18. In each of the second inlet and outlet pipes 44 and 48, there is defined on a distance of approximately eight inches a number of holes equal to the number of coiled tubes 38 present in the secondary circuit 18, with these holes having a diameter corresponding to the diameter of the tubing of the coiled tubes 38. The lower and upper ends 42 and 46 of the coiled tubes 38 are then secured, e.g. by welding, respectively to the second inlet and outlet pipes 44 and 48. The short distance and the small surface about which are connected the coiled tubes to the second inlet pipe 44 produce a mixing of the secondary fluid and a homogeneous distribution thereof in the coiled tubes 38. It is noted that the coils of each coiled tube 38 has a pitch of 0.625 inch for permitting a better circulation of the heating fluid of the primary circuit 16 between the coils of the coiled tubes 38 and ensure a uniform temperature therein.

The efficiency obtained with the present fluid device D is presently explained by a combined effect of the centrifugal acceleration of the water in the coiled tubes 38 and of the vibrations of the deuterium molecules contained in the water of the secondary circuit 18 due to the contribution of outside heat from the primary circuit 16, all of this permitting an interaction between the atoms, the molecules having been permitted, due to the length of the coiled tubes 38, to become oriented in a homogeneous fashion under the effect of the centrifugal acceleration.

Regarding the coiled tubes 38, it is contemplated to replace the illustrated tubes of annular cross-section with tubing having a crescent- shaped cross-section with the convex portion thereof being oriented outwardly of the coiled tube, whereas the concave portion of the coiled tube is inwardly directed. Such a modified tubing 138 is shown in Figure 5. Indeed, as seen in Figure 5, modified coiled tubes can define a non-annular cross-section as opposed to the coiled tubes 38 of Figs. 1 and 4 in which the tubing is cylindrical. The tubing 138 of Fig. 5 is crescent-shaped to increase the surfaces of heat transfer with the heating fluid. A convex wall 140 of the tubing 138 is positioned on the outside of the coil whereas the inside wall 142 of the tubing 138 is concave. The molecules of the fluids to be heated under the centrifugal forces takes position along the outside of the coil and thus against an inside surface 144 of the outer convex wall 140.

It is noted that the second inlet pipe 44 can extend outside of the tank 10 so as not to be pre-heated by the heating fluid prior to its high- speed displacement in the coiled tubes 38, thereby increasing the temperature differential and thus the thermal shock occurring between the heated fluid and the heating fluids in the coiled tubes 38 and favouring the energy releasing reaction in the water of the secondary circuit 18. Furthermore, the beginning or lower end of each coiled tube 38 can be located in a location such that it is not immersed in the heating fluid (without interrupting the coiled configuration of the tubes 38) so that the gyratory speed of the heated fluid is obtained before the aforementiond thermal shock.

Obviously, the heated fluid of the secondary circuit 18 exiting the second outlet pipe 48 is then available for domestic or other use, such as domestic hot water and domestic heating. If the heated fluid is only used for domestic heating, the secondary circuit is closed, whereas if some or all of the heated water is used for instance as domestic hot water it will be necessary to periodically add fresh water to the secondary circuit 18. Obviously, where the heated fluid is used as domestic hot water, the fluid circulating in the secondary circuit 18 is water, whereas other fluids, such as oil, could also be circulated in the secondary circuit 18 for instance in closed circuits used for heating a dwelling.

Claims

CLAIMS :

1. A fluid heating device comprising a container means, primary fluid circuit means having first inlet and outlet means, secondary fluid circuit means having second inlet and outlet means, a heating fluid and a fluid to be heated circulating respectively in said primary and secondary fluid circuit means, said secondary fluid circuit means comprising at least one coiled tubing means extending in said container means between said second inlet and outlet means and being substantially immersed in said heating fluid, said heating fluid being supplied to and withdrawn from said container means respectively by said first inlet and outlet means with said heating fluid and said fluid to be heated flowing substantially in a co-current manner, flow distribution means being provided substantially uniformly distributing said heating fluid on said coiled tubing means while causing turbulence in said heating fluid so that said heating fluid substantially uniformly heats said coiled tubing means thereby improving the heat exchange between said primary and secondary fluid circuit means.

2. A fluid heating device as defined in Claim 1, wherein said flow distribution means comprise an injection plate means disposed between said first inlet means and said coiled tubing means.

3. A fluid heating device as defined in Claim 2, wherein said secondary fluid circuit means comprises a series of substantially parallel and spaced apart coiled tubing means with said injection plate means extending substantially at right angles to longitudinal axes of said coiled tubing means.

4. A fluid heating device as defined in Claim 3, wherein said injection plate means defines a series of openings disposed in groups opposite said coiled tubing means.

5. A fluid heating device as defined in Claim

1, wherein a suction plate means is provided in said container means between said coiled tubing means and said first outlet means.

6. A fluid heating device as defined in Claim 5, wherein said suction plate means defines openings distributed thereon along concentric rings.

7. A fluid heating device as defined in Claim 5, wherein an expansion chamber is defined in said primary fluid circuit means downstream of said suction plate means.

8. A fluid heating device as defined in Claim

2, wherein heating means are provided in said primary fluid circuit means for said heating fluid upstream of said injection plate means.

9. A fluid heating device as defined in Claim 1, wherein said fluid to be heated is water.

10. A fluid heating device comprising a container means, primary fluid circuit means having first inlet and outlet means, secondary fluid circuit means having second inlet and outlet means, a heating fluid and a fluid to be heated circulating respectively in said primary and secondary fluid circuit means, said secondary fluid circuit means comprising a series of coiled tubing means extending in a spaced apart and substantially parallel relationship in said container means between said second inlet and outlet means and being substantially immersed in said heating fluid, said heating fluid being supplied to and withdrawn from said container means respectively by said first inlet and outlet means with said heating fluid flowing substantially co-current with said fluid to be heated, each of said coiled tubing means having slightly spaced apart coils and defining a substantially limited gyratory radius in order that said fluid to be heated flows therein with a substantially high centrifugal acceleration such that an efficiency of said fluid heating device is above 100%.

11. A fluid heating device as defined in Claim 10, wherein an upstream end of each of said coiled tubing means is not submerged in said heating fluid.

12. A fluid heating device as defined in Claim 10, wherein said fluid to be heated is water.

13. A fluid heating device as defined in Claim

10, wherein said primary fluid circuit means comprise flow distribution means for substantially uniformly distributing said heating fluid on said coiled tubing means.

14. A fluid heating device as defined in Claim 13, wherein said flow distribution means comprise an injection plate means disposed between said first inlet means and said coiled tubing means.

15. A fluid heating device as defined in Claim

14, wherein said injection plate means extend substantially perpendicularly to longitudinal axes of said coiled tubing means.

16. A fluid heating device as defined in Claim

15, wherein said injection plate means defines a series of openings disposed in groups opposite said coiled tubing means.

17. A fluid heating device as defined in Claim

16, wherein a suction plate means is provided in said container means between said coiled tubing means and said first outlet means, said suction plate means defining a plurality of openings.

18. A fluid heating device as defined in Claim

17, wherein an expansion chamber is defined in said primary fluid circuit means downstream of said suction plate means.

19. A fluid heating device as de^fined in Claim 14, wherein heating means are pi ided in said primary fluid circuit means for said heating fluid upstream of said injection plate means.

20. A method of heating a fluid comprising the steps of:

21. A method as defined in Claim 20, wherein said fluid contains certain elements of the hydrogen family.

22. A method of heating a fluid comprising the steps of:

23. A method as defined in Claim 22, wherein said fluid contains certain elements of the hydrogen family.