CN1293745A

CN1293745A - Flue and hot water heater

Info

Publication number: CN1293745A
Application number: CN 99804124
Authority: CN
Inventors: B·V·伯克
Original assignee: Southcorp Australia Pty Ltd
Current assignee: Rim Australia PTY. Ltd.
Priority date: 1998-03-20
Filing date: 1999-03-19
Publication date: 2001-05-02
Also published as: WO1999049268A1

Abstract

A flue is adapted to communicate exhaust gases from one end of a heater to the other. The flue includes a central internal core, and an elongate generally cylindrical outer tube which surrounds the central core. The outer tube has a corrugated configuration in cross section thereby defining a plurality of corrugations. The internal surface of the outer tube is in contact with the core so that the corrugations define a series of air passages around the core. Exhaust gases flow through those passages in use. A series of different configurations of corrugations are defined. The invention extends to a water heater which incorporates a flue, and furthermore, to a water heater which includes a central flue which leads to an annular space around the outside of the water vessel, exhaust gases flowing upper the central flue and into the annular space before exhausting from the water heater.

Description

Flue and hot-water heater

Invention field

The present invention relates to be used for such as combustion gas and fuel oil type space, water heater device or other utilizes waste gas that the flue of the utensil of heating is provided, and relate to water heater.

Background of invention

Occasion at water heater, flue is generally metal cylinder, they can be by glazing, and the inside can be provided with heat exchange elements, such as issuing and laid-open U.S. Patents 3349754 in United States Patent (USP) 2950740 or on October 31st, 1967 open in August 30 nineteen sixty and that issue.

Fluid heater such as water heater has in the container that is arranged on a fluid to be heated and extends to the flue of upper end from the container lower end.This flue has a passage, and heat supply waste gas moves into place in the exhaust apparatus of container top from the combustion chamber that is positioned at the container below.

Concerning flue importantly, provide one with respect to flue path cross-sectional area for bigger heat transfer surface.This will guarantee to have the conductive surface area of increasing, thus fluid that can more heat transferred are to be heated.

A problem of the flue of prior art is that the difference place on flue length often is easy to generate focus.This can be by the temperature in the fin and be subjected to fin with heat be passed to walling of flue and and then the ability that is passed to fluid to be heated be in a ratio of too many heat and caused.

The generation of focus can make the enamel on flue stream side break or be cracked, and then flue corroded, thereby reduces the service life of heater.

The heater of the above-mentioned type is well-known, and is used for adding hot water widely in industry and family expenses occasion.Because efficient, outbalance be that the calorific value at high proportion of the heat that burning is discharged passes to water to be heated.For this reason, the past had also once used design of dissimilar flue and water receptacle to design, in them some efficient is also higher comparatively speaking.

Had that a kind of to prove comparatively successful structure be to adopt an inner flue past, just the flue by water receptacle central authorities upwards.But it is found that, adopt such design, the gas of discharging from the flue top is still warmmer relatively.When such gas was discharged into atmosphere, the heat that is lost was also well imagined.

Brief summary of the invention

According to one aspect of the present invention, provide a kind of being suitable for that waste gas is led to the flue of the other end from an end of a heater, this flue comprises:

One central inner core;

One around this central authorities' inner core, that made by Heat Conduction Material, cylindrical circular substantially elongated outer tube, and the cross section of this outer tube becomes ripple struction and forms a plurality of ripples, and this outer tube has an inner surface and an outer surface;

This inner surface contacts with inner core on the partial-length at least of outer tube, and this outer surface contacts with treating the fluid by the heater heating; And

Form one or more air duct between ripple and the inner core, in use flow through for waste gas.

Best, inner core is a tubular structure solid or sealing, makes that in use waste gas is tied and upwards passes through air duct.

Best, the heat transfer surface area that described passage provided that is formed by described ripple and the ratio of flue path volume are greater than finned flue.

Best, described ripple is axially aligned with the flue axis on the partial-length at least of flue.Alternative plan is that ripple extends along at least a portion length of described flue with a helical path around the inner core outside.

The inner surface of outer tube can be connected in inner core at the contact point place between outer tube and the inner core.

Inner core can be a tubular structure, and it has an inner passage by wherein one or more baffle plate blocking-up.Inner core can be out of shape corresponding to the ripple on the outer tube, and ripple is nested in the distortion of inner core.

Alternative plan is, ripple is to be formed at outer tube by a kind of cold working operation of carrying out under the situation of outer tube appropriate location that is arranged at inner core, and the inner radial of this ripple is made with the outer surface of inner core and contacted.Inner core itself can be out of shape in described operation and the described inner radial of admitting ripple.

Best, described ripple has a contact surface that contacts with described inner core between adjacent corrugations, described contact surface is provided as following one or more form: a concave surface, a convex surface, a solder side, a radius and described in the surface that is complementary of core outer surface, one and the surface of the outer surface essentially concentric of described inner core.

Best, described flue has a top and a bottom that is the right circular cylinder bodily form.

Best, this flue is suitable for being installed in the water heater.The present invention also extends to the water heater of the corrugated flue that is equipped with here to be limited.

Best, described ripple centers on the circumference of inner core substantially equably and distributes.

Best, this ripple has the amplitude greater than the outer tube wall thickness.

The cross section of this ripple can be the sine curve shape.

This ripple can have one and be parallel to the first of flue axis and the second portion of a helical structure, and this second portion is positioned at the downstream of first.

Best, the inner radial of this ripple can prevent that by one jockey that ripple and inner core disengage is connected in inner core along the corresponding length of length that in use is in usually under the scaling temperature with inner core of inner core.

Best, described jockey is following one or more: embossing, welding, spot welding, vacuum welding.

According to second aspect of the present invention, a kind of water heater is provided, it comprises:

One has the water receptacle of an inner flue, and this inside flue extends through this container substantially vertically from container bottom and arrives a flue outlet of container portions;

The heater that be used to apply heat adjacent, this heater with container bottom have a burner and with waste gas from burner guiding fan by flue;

One around to the small part container and be spaced from and around container forms the shell in a ringwise substantially space, described annular space and described flue outlet fluid communication; And

One exhaust apparatus from described annular space exhaust.

Its structure make make waste gas before discharging heater by exhaust apparatus earlier by inner flue and pass through annular space.

Best, shell surface has the guide of flow structure on the part surface at least of annular space.These guide of flow structures can be the forms of described lip-deep a series of burrs or protruding grain.Perhaps, described guide of flow structure form that can be blade, fin, ripple or other fluid flow direction shape.The another kind of scheme of guide of flow structure is only the inner surface of shell to be carried out surface treatment.Alternative plan is to have blade, fin or other structure on the outer surface of container equally.

Can make part shell thermal insulation at least, can be at least make the shell thermal insulation forming on described annular space that part of.

Container and shell preferably all are the right circular cylinder bodily form substantially, and annular space is preferably in it and has substantially invariable width on partial-length and around the whole circumference of container at least.

Above-mentioned and its its feature of the present invention will become more clear after a following embodiment who proposes with example forms is described.Reference is accompanying drawing in description, but the concrete feature shown in the accompanying drawing should not be considered to the restriction to invention scope.

The accompanying drawing summary

Fig. 1 is the front view of the flue of one embodiment of the invention;

Fig. 2 is the vertical view of flue shown in Figure 1;

Fig. 3 represents that the flue of Fig. 1 and 2 is arranged on a forced ventilation water heater;

Fig. 4 is the vertical view of the flue of second embodiment;

Fig. 5 is the vertical view of the flue of the 3rd embodiment;

Fig. 6 is the vertical view of the flue of the 4th embodiment;

Fig. 7 is the front view of the flue of the 6th embodiment;

Fig. 7 A is the vertical view of flue shown in Figure 7;

Fig. 8 is the front view of the flue of the 6th embodiment;

Fig. 8 A is the vertical view of flue shown in Figure 8;

Fig. 9 is the front view of the flue of the 7th embodiment;

Figure 10 is the front view of the flue of the 8th embodiment;

Figure 11 represents a cross section of the flue of the 9th embodiment;

Figure 12 represents the cross section of the tenth embodiment; And

Figure 13 is the sectional view of a water heater of the present invention.

The detailed description of embodiment

A flue 2 has been shown among Fig. 1 and 2, and it has a upright tubular top and a bottom, represents with

label

4 and 6 respectively.Extending between

end

4 and 6 is a middle section 7, and its profile or shape are made and formed a plurality of ripples 8, and as shown in the vertical view of Fig. 2, these ripples roughly are the sinusoidal shape around an inner core 10.The trough of ripple 8 or inner radial 12 are at least along a part of length of flue and contact with inner core 10.

Ripple 8 forms a series of passages that separate 9 with inner core along flue.Passage 9 shown in Fig. 1 and 2 is straight, and with the longitudinal axis alignment of flue.

Inner core 10 contacts with ripple 8 and can guarantee that the heat that inner core 10 is absorbed is delivered in the material of ripple 8, and then is delivered to the fluid that centers on ripple 8 in a heater.

Inner core 10 comprises a sealed tube 11.One end of sealed tube 11 is sealed by a disk 14 that is welded in sealed tube 11 ends.Lower end 16 is open, thereby waste gas can move into the internal capacity of interior pipe 10.In case waste gas runs into disk 14, other any gas of attempting to enter will change route shown in along the line 18 into and enter by ripple 8 formed passages 9.Like this, just do not provide by inner core 10 from the following cylindrical end of flue 6 to its on the passage that communicates of cylindrical end 4, thereby can guarantee that waste gas upwards flows through all passages 9.As mentioned above, inner core 10 forms a baffle plate effectively, thereby along a special route guidance waste gas.

As shown in Figure 3, by

cylindrical end

4 and 6 being welded in the

end

24 and 26 of container respectively, thereby flue 2 can be installed in the water receptacle 20.

Container end

24 and 26 so-called anodes, this is because they can be container 20 extra volume is provided.In container shown in Figure 3 20, has a combustion chamber 28 in the container end 26.This combustion chamber 28 is centered on by the water of the volume 30 that pours into container 20.

In the embodiment shown in fig. 3, waste gas is discharged flues 2 by cylindrical end 4, and enters an outside annular waste air duct 32, and this exhaust passage makes it flow out flue 2 along route 34 direct exhaust, then around container 20 to dirty, and flow out from exhaust apparatus 36.

Shown in Fig. 4 is the vertical view of flue 2A of a band groove, and it is similar to the flue of Fig. 2, just ripple 8A have one with outer surface or the concentric bottom 12A of circumference of inner core 10A.Surface 12A can provide along the length of ripple 8A and contact with the surface of inner core 10A.

Shown in Fig. 5 is the vertical view of the flue 2B of a band groove.In this embodiment, the flue 2B of band groove is such, and promptly the bottom 12B of ripple 8B charges into the internal capacity of inner core 10B.This will provide the contact surface of an arc long-pending, and it compares bigger with the surface area of the flue 2A of Fig. 4.

Shown in Fig. 6 is the flue 2C of a band groove, and wherein bottom 12C is welded in inner core 10C along the whole length of ripple.

Shown in Fig. 7 is one to be similar to band groove flue 2D shown in Figure 1, different is, locate in the end of band groove flue 2D, just relative with disk 14D end, ripple 8D is welded in inner core 10D (the preferably tubular structure of being made by mild steel or carbon steel) by their bottom 12D.Welding can comprise a series of spot welding 50 that separate along the length of bottom 12D on a vertical line.Though this spot welding 50 can entirely be extended along the length of flue 2D, they are even more important at the upstream region of flue 2D.If there is not spot welding 50, this zone of flue 2 will be stood the temperature of scaling usually.

In 10% to 20% part of the bottom of tubular core 10D or upstream, or in 100 millimeters to 200 millimeters of inner core 10D, if bottom 12D separates with interior pipe 10D, then may scaling.If bottom 12D separates with 10D, then inner core 10D can't dissipate the heat that it absorbed or be passed to water or other medium that is positioned at the outer tube 11A outside.If this separation takes place, the temperature of the inner core in this upstream region will be raised to more than 500 ℃, thereby mild steel or carbon steel will begin gas oxide skin.The scaling meeting reduces the heat-transfer capability of flue 2D because of material production is expanded.This expansion can cause formed one or more passage of ripple to stop up or part is stopped up.Another problem of scaling is the danger of burning skin or particle, and they may be fallen on the burner and stop up its spout and cause damage, or causes some other problem.

If necessary, spot welding 50 can fetch replacement with the sequential welding in the same area.Perhaps, between inner core 10D and the outer tube 11D bottom 12D place be connected can by following any or its make up and realize: vacuum welding, embossing, intermittently welding, spot welding or continuous welding.

The another kind of solution of scaling problem is formation one band groove flue 2E as shown in Figure 9.This flue 2E can be by eliminating the possibility of scaling with the upstream extremity of a ceramic plug 13E sealed tubular inner core 10E, this ceramic plug occupies that segment length that tubular core 10E may scaling.Ceramic plug 13E has eliminated necessity that a downstream end disc 14 is set as shown in Figure 1 because interior pipe 10E in its lower end or upstream extremity sealed by ceramic plug 13E.

Ceramic plug 13E can have a tapering point 15E, and it is the shape of taper shape, cone-shaped, hemispherical or other taper, thereby the glide path of the waste gas by end 15E is applied less resistance.

The another kind of scheme that prevents scaling be with the stainless steel tube of a segment length make tubular core 10 and form may scaling that part of inner core 10, the remainder of inner core 10 is made of the identical flexible metallic hose in inside and outside footpath.Mild steel and stainless steel tube can be welded in and form a single continuous inner core together, any position on its length is all sealed.

The stainless steel that selection is used for this occasion should be a heat-resistance type, such as AISI310 or AISI321 or AISI430 or AISI316.The inner core 10 of Zhi Zaoing can seal with a mild steel disk 14 in the mild steel end in this way, or seals with a similar disk of being made by stainless steel in the stainless steel end of interior pipe.If desired, the stainless steel end can have pyramidal structure, and its shape is similar to the end shape of the ceramic plug 13E of Fig. 9.

Shown in Fig. 8 is the flue 2F of a band groove, and it has the downstream that starts from flue 2F and is parallel to the ripple 8F of the longitudinal axis of inner core 10.Along in certain segment distance of flue 2F length, ripple 8F becomes spirality, shown in label 17F.The purpose of doing like this is to allow waste gas have longer route to leave flue 2F, thereby along with heat transmits to come out and their temperature reduces from waste gas, remaining heat can therefrom be discharged by long route, allow diabatic process that the longer time is arranged.Helical fissure can be parallel to each other with an angle of fixing with respect to inner core axes, as shown in Figure 8.

Perhaps, ripple 17F can begin with a less helical angle, and this helical angle is advanced towards the upstream along with ripple 17F and increased gradually.The variation of helical angle or increase speed and may be selected to the speed complementation of from waste gas, discharging with heat, thereby the waste gas that leaves flue 2F will have predetermined temperature, and can keep not having the efficient of adverse current flue.

As shown in Figure 10, two helical fissure 8J are only arranged on the flue 2J.These ripples will have relatively large cross-sectional area.Owing to two ripple 2J are only arranged, thereby each ripple is made the rotation two whole circles along a helical path around inner core.If more ripple is arranged, then can reduce the number of turns or helical angle.

For guaranteeing the maximal heat transfer amount of above-mentioned any ripple, need come the body plan ripple like this, promptly the size of cross-sectional area is made and is made the ultimate range of separating ripple sidepiece or ripple and inner core be not more than about 12 millimeters.These sizes have now found that, if greater than 12 millimeters, then can be reduced the validity of the flue of being assembled by the effect of boundary layer that waste gas produced of the ripple by this size.Between all surfaces of ripple or the ultimate range of the best between surface of ripple and the inner core be 8 millimeters.

Best, be used for substituting the flue of a prior art at one, promptly on the flue of four inches or 100 millimeters, 2 to 8 ripples arranged.But we think that the most effective structure is to have about six ripples, shown in Fig. 1 to 9.

The advantage of these embodiment is, is about 100 millimeters external dimensions for

cylindrical end

4 and 6 places, and flue 2 can use with a burner that can produce about 100,000,000

burnt energy.Flue

2,2A, 2B and the 2C of band groove are meant with about 80% efficient work, have 80,000,000 Jiao's heat to make the water heating that is adjacent approximately by flue.And in and the United States Patent (USP) 2950740 issued open in August 40 nineteen sixty or issued on October 31st, 1967 with the sort of finned flue shown in the laid-open U.S. Patents 3349754 conventional flue, typical 4 inch diameter flues of this structure the ceiling capacity that can pass through have only 45,000,000 Jiao approximately.

Make more heats by such as those mild steel glazing flues that disclosed in above-mentioned United States Patent (USP) if desired, these energy of adding out can cause the enamel on these flues to break because of the focus that fin tie point place produces usually.It is contemplated that corrugated flue described herein is subjected to the degree of this problem puzzlement less.

Another advantage of the present invention is only have

band groove flue

2 and 2A to need glazing to the outer surface of 2J.This is because by making flue with about 80% efficient work, just do not have the danger that condensation takes place in flue, otherwise the generation meeting corrosion device of condensation maybe may produce water droplet, water droplet drops on the hot surface and produces steam, the existence of steam and then can stop up flue.

Flue

2 and 2A are to another advantage of 2J, owing to increased the surface area of ripple, do not have focus substantially and emerge on flue.Why this is an advantage, is because the focus enamel reason of breaking normally in case enamel breaks, can produce corrosion and other deterioration very soon on the water side of flue.

Flue

2 and 2A be to another advantage of 2J, because its shape and structure compare with the flue of circular flue or even those band fin inner surfaces, suchlike flue can be worked under a much higher heat transfer rate.This means that the total height of implementing water heater of the present invention, as to have above-mentioned flue is reduced, thereby required manufactured materials is also just less.

Another advantage is, can make water heater have less storage volumes, and therefore, water heater will have more rapidly recovery time and make water go back up to required water temperature.

Water heater shown in Fig. 3 is a kind of full condensation type.Yet, implement above-mentioned flue of the present invention and can be used for non-condensing fan or forced ventilation water heater, and can provide such advantage (as long as all ripples are apart enough far away) by this flue, promptly water heater does not have the standby loss.This is because gravity-flow ventilation or convection current can not passed through ripple because of the resistance that ripple applied.When ripple had the helical path that centers on interior pipe at least in part, this effect was more remarkable.

Shown in Figure 11 and 12 is the cross section of two flue 2K and 2L in addition.Flue 2K and 2L are made by one first plate 70, and this first plate extends into and extends the drawing page, thereby the flue of a segment length is provided.The end can have a transition plate, so that a cylindrical end to be provided, is used for flue 2K and 2L are connected in the end of a water receptacle.

Flue 2K has one and is corrugated and covers second plate 72 that places on the plate 70, thereby three

parallel passages

71,73 and 75 are provided.The structure of flue 2L is similar, but it has one the 3rd plate, 74, the three plates and cover equally and place plate 70, just to cover the surface of putting be at the opposite side that plate 72 is set.The 3rd plate 74 is corrugated, and itself with first plate 70 between form three parallel

longitudinally extending channels

77,79 and 81 in addition.Passage 71 with 77 as

passage

73 and 77 and

passage

75 and 81, also be in back-to-back position.

Compare with finned flue, the heating surface of the flue that these embodiment of the present invention produced is higher with the ratio of flue path volume, thereby heat-transfer capability is higher than finned flue.This is not because heat transfer surface is long-pending have been increased, but because less passage (comparing with the heat transfer surface area that it is provided) is provided, causes the convection velocity increase by the waste gas of passage.The increase of convection velocity is bringing out of providing because of fan or air blast or forced ventilation, is produced by the increase of the exhaust gas velocity by passage.Waste gas is only guided by by the formed passage of ripple, a certain amount of heat transfer surface area can be provided, thereby maximally utilise the waste gas that flows fast and draw heat as much as possible therefrom.

Translate into Figure 13 below, hot heater 100 comprises a container 112, and this container has one and is roughly columnar sidewall 114, a bottom 116 and top 118.Container 112 is preferably made by mild steel, its inside and outside equal glazing.If desired, be positioned at the outside enamel can replace by epoxy coating.

Inner flue 120 116 extends to top 118 from the bottom, and ends in the flue outlet 122 at the place, top of container.Flue 120 in the preferred embodiment is made by resistant material, and can be the ripple struction of aforesaid way.Flue 120 is formed by a pair of coaxial nested each other tube-like piece, and the outer tubular part is a ripple struction, forms the ripple by label 124 expressions.As already described above, this ripple struction can provide good heat exchange characteristics for the inside area of heating surface of container.This container has a water inlet 126, for cold water is introduced container, and has a near water out 128 that is arranged on the container top, and heat supply water is discharged from the container.

Container 112 is around there being a shell 130, and shell 130 is made of a heat-insulating material.Shell 130 separates with the top 118 and the sidewall 114 of container, space 132 of formation between the inner surface that makes shell 130 and the outer surface of container 112.Space 132 is structure ringwise roughly, and its forms one and flows out the flow channel of flue outlet 122 for waste gas.

This water heater has a burner 134, and this burner is provided with combustion gas by a feeder 136 and gas pipeline 38.Fan 140 forces the gas after the burning upwards to pass through flue 120 towards flue outlet 122, thereby gas is by the forced flow of saying so in a way that is flowing in of flue.

Being arranged on annular space 132 from flue outlet 122 effluent airs along arrow 42 directions towards one descends the air exit 144 of point to flow most.Like this, the gas of heating contacts with container 112 in upwards by the process of flue 120 at it, and contacts with container once more during downwards by annular space 132 towards air exit 144 in heated air.This just guaranteed gas before air exit 144 is discharged the gas available heat of big ratio conducted to container 112, thereby guarantee relatively efficiently contained water in the heating container.

We find, the performance of water heater can be by on the inner surface of shell, just facing and form the guide of flow structure on the surface of annular space 132 and be improved.The guide of flow structure especially has the effect of breaking in the boundary layer that makes the waste gas that is passed through.In this embodiment, these guide of flow structures adopt the form of burr or protruding grain.The effect of these burrs or protruding grain is, is subjected to the interference of protruding grain downwards by the gas laminar flow of annular space to a certain extent, thereby guarantees that the gas and the container outer surface that heat keep in touch, and make heat from the gas transfer to the container.As previously mentioned, the guide of flow structure that certain form also is provided on the outer surface of container is to help heat from the gas transfer to the container, and this equally also can be favourable.

The position of air exit in shell 130, the distance of promptly being separated by with it below shell 130 tops depend on million Jiao's/hour measure burner input and the secondary unit required surface area of condensation under dew point to heater.

Gas is discharged flue collector (central flue tube), condensation on the outer surface of container 112 housings then more than dew point.For realizing sufficient condensation, temperature must be reduced to below the dew point, and the latent heat of condensation is discharged from flue gas.In this case, dew point is about 65 ℃ usually, and only requires to be cooled to more than the water temperature little by little number of degrees.Best, condensation is limited in the outside of container 112, because this easier control condensate and prevent corrosion.

Therefore, if the heat input increases, then need bigger heat exchange area (promptly limiting the container surface area on annular space 132 borders), or need annular space 132 that littler cross-sectional area is arranged.Small cross section is long-pending can to increase exhaust gas velocity, but needs bigger fan as precondition.

Without departing from the present invention, the foregoing description can have many versions.For example, container can form and be different from above-mentioned form slightly, and the structure of shell can be different from shown in this article equally.But the applicant thinks that the structure shown in the accompanying drawing manufactures comparatively cheap, and can provide efficiency characteristic higher relatively water heater.

Be appreciated that here institute's invention of disclosing and limiting and may extend into specification or accompanying drawing is described or shown in all alternative combinations of two or more independent feature.All these are different has constituted various alternative aspect of the present invention.

More than describe embodiments of the invention, for those skilled in the art, obviously can also make multiple modification without departing from the scope of the invention.

Claims

1. one kind is suitable for waste gas is led to the flue of the other end from an end of a heater, and this flue comprises:

One central inner core;

2. flue as claimed in claim 1 is characterized in that, inner core is a tubular structure solid or sealing, makes that in use waste gas is tied and upwards passes through air duct.

3. the described flue of each claim as described above is characterized in that, the heat transfer surface area that described passage provided that is formed by described ripple and the ratio of flue path volume are greater than finned flue.

4. the described flue of each claim as described above is characterized in that described ripple is axially aligned with the flue axis on the partial-length at least of flue.

5. the described flue of each claim as described above is characterized in that, ripple extends along at least a portion length of described flue with a helical path around the inner core outside.

6. the described flue of each claim as described above is characterized in that the contact point place of the inner surface of outer tube between outer tube and inner core is connected in inner core.

7. the described flue of each claim as described above is characterized in that inner core is a tubular structure, and it has an inner passage by wherein one or more baffle plate blocking-up.

8. flue as claimed in claim 7 is characterized in that, the upper end when this inner passage is arranged on flue work by one or the plate sealing of its vicinity.

9. the described flue of each claim as described above is characterized in that inner core is out of shape corresponding to the ripple on the outer tube, and ripple is nested in the distortion of inner core.

10. the described flue of each claim as described above, it is characterized in that, described ripple is to be formed at outer tube by a kind of cold working operation of carrying out under the situation of outer tube appropriate location that is arranged at inner core, and the inner radial of this ripple is made with the outer surface of inner core and contacted.

11. flue as claimed in claim 10 is characterized in that, this is out of shape inner core and the described inner radial of admittance ripple in described cold working operation.

12. the described flue of each claim is characterized in that as described above, described ripple has a contact surface that contacts with described inner core between adjacent corrugations, and described contact surface is made into following one or more form:

One concave surface, a convex surface, a solder side, a radius and described in the surface that is complementary of core outer surface, one and the surface of the outer surface essentially concentric of described inner core.

13. the described flue of each claim is characterized in that as described above, described flue has a top and a bottom that is the right circular cylinder bodily form.

14. the described flue of each claim is characterized in that as described above, it is particularly suitable for being installed in the water heater.

15. the described flue of each claim is characterized in that as described above, described ripple centers on the circumference of inner core equably and distributes.

16. the described flue of each claim is characterized in that as described above, this ripple has the amplitude greater than the outer tube wall thickness.

17. the described flue of each claim is characterized in that as described above, the cross section of this ripple is the sine curve shape.

18. the described flue of each claim is characterized in that as described above, this ripple has one and is parallel to the first of flue axis and the second portion of a helical structure, and this second portion is positioned at the downstream of first.

19. the described flue of each claim as described above, it is characterized in that the inner radial of this ripple is by one preventing jockey that ripple and inner core disengage, being connected in inner core along the corresponding length of length that in use is in usually under the scaling temperature with inner core of inner core.

20. flue as claimed in claim 19 is characterized in that, described jockey is following one or more:

Embossing, welding, spot welding, vacuum welding.

21. water heater that the described corrugated flue of aforementioned each claim is housed.

22. a water heater, it comprises:

One exhaust apparatus from described annular space exhaust.

23. water heater as claimed in claim 22 is characterized in that, shell surface has the guide of flow structure on the part surface at least of annular space.

24. water heater as claimed in claim 23 is characterized in that, these guide of flow structures are forms of described lip-deep a series of burrs or protruding grain.

25. water heater as claimed in claim 23 is characterized in that, described guide of flow structure is any form or other the fluid guiding shape of blade, fin, ripple.

26. water heater as claimed in claim 23 is characterized in that, described guide of flow structure comprises the surface treatment to the inner surface of shell.

27. each the described water heater as claim 22 to 26 is characterized in that having the guide of flow structure on the outer surface of container.

28. each the described water heater as claim 22 to 27 is characterized in that, to the small part shell by thermal insulation.

29. each the described water heater as claim 22 to 28 is characterized in that container and shell all are the right circular cylinder bodily form substantially, annular space has substantially invariable width on the partial-length and around the whole circumference of container at least at it.

30. each the described water heater as claim 22 to 29 is characterized in that, the type that each limited that described inner flue is a claim 1 to 21.

31. one kind basic with reference to the described in front flue of any embodiment shown in the accompanying drawing.

32. one kind basic with reference to the described in front water heater of any embodiment shown in the accompanying drawing.