CN111649485A

CN111649485A - Condensation heat exchange structure and gas water heater

Info

Publication number: CN111649485A
Application number: CN202010579937.4A
Authority: CN
Inventors: 王志昂; 张果; 林钦; 林玉绵; 瞿福元
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2020-06-23
Filing date: 2020-06-23
Publication date: 2020-09-11

Abstract

The invention relates to a condensation heat exchange structure and a gas water heater. The condensation heat transfer structure includes: a shell and a heat exchange tube; a smoke inlet is arranged on the side wall of the shell, and a smoke outlet positioned above the smoke inlet is also arranged on the wall of the shell; the heat exchange tube is circuitously bent along the cross section of the shell to form a hollow structure, an air passing gap is formed between the heat exchange tube and the inner wall of the shell, and a water inlet and a water outlet are respectively arranged on the head and the tail of the heat exchange tube. The heat exchange tube is circuitous and bent to form a hollow structure, so that the resistance to the flue gas flowing through the gas passing gap is the same as the resistance to the gas passing channel flowing through the hollow structure, the flue gas is uniformly distributed, most of the flue gas is prevented from flowing through the gas passing channel in the hollow structure, and the heat exchange efficiency of the condensation heat exchange structure is improved. In addition, the heat exchange pipe is bent along the direction of the cross section of the shell in a circuitous manner, so that the flowing path of cold water in the heat exchange pipe can be increased, the heat exchange time with the flue gas in the shell can be prolonged, and the waste heat of the flue gas can be fully utilized to improve the heat exchange efficiency.

Description

Condensation heat exchange structure and gas water heater

Technical Field

The invention relates to the technical field of water heaters, in particular to a condensation heat exchange structure and a gas water heater.

Background

The traditional gas water heater generally utilizes the heat exchanger of the self-heating component to absorb heat generated by burning gas and transmit the heat to cold water of the heat exchanger with the flow of the water inlet pipe, the water temperature rises after heat exchange, hot water is discharged from the water outlet pipe, meanwhile, smoke generated by burning is pumped out of a room through a smoke chamber by a fan, wherein more than 10% of heat is discharged along with the smoke, the waste heat in the smoke cannot be fully utilized, and the energy is greatly wasted. In order to solve the problem, a condensation heat exchange structure is generally arranged at a smoke outlet of the fan at present to absorb heat in smoke.

The existing condensation heat exchange structure generally comprises: the heat exchange tube is a frustum-shaped cylinder body which is formed by spirally winding a metal corrugated pipe, one end of the frustum-shaped cylinder body is adjacently matched with a smoke inlet pipe of the shell, and the other end of the frustum-shaped cylinder body is adjacent to a smoke exhaust pipe of the shell. However, the heat exchange tube of this kind of frustum shape barrel leads to the flue gas to distribute inhomogeneous for most flue gas flows away from self intermediate channel, thereby makes condensation heat transfer structure's heat exchange efficiency low.

Disclosure of Invention

Based on this, it is necessary to provide a condensation heat transfer structure and gas heater to the problem that current condensation heat transfer structure leads to condensation heat transfer structure's heat exchange efficiency to hang down because the flue gas distributes inhomogeneously.

A condensation heat exchange structure comprising: a shell and a heat exchange tube;

a smoke inlet is formed in the side wall of the shell, and a smoke outlet positioned above the smoke inlet is also formed in the wall of the shell;

the heat exchange tube is bent along the cross section of the shell in a circuitous way to form a hollow structure, an air gap is formed between the heat exchange tube and the inner wall of the shell, and a water inlet and a water outlet are respectively arranged on the head and the tail of the heat exchange tube.

The condensation heat exchange structure can be applied to a gas water heater, smoke discharged by a fan of the gas water heater enters the shell through the smoke inlet of the shell, one part of the smoke flows into the air passing gap formed between the heat exchange tube and the inner wall of the shell, cold water close to the outer wall of the heat exchange tube exchanges heat in the process of flowing to the smoke outlet, the other part of the smoke flows into the hollow structure formed by the heat exchange tube in a circuitous bending mode, and the cold water close to the inner wall of the heat exchange tube exchanges heat in the process of flowing to the smoke outlet, so that the uniform heat exchange of the cold water is ensured. Because the heat exchange tube is circuitous and bent to form a hollow structure, the resistance of the flue gas flowing through the gas passing gap is the same as the resistance of the gas passing channel in the hollow structure, the uniform distribution of the flue gas is ensured, most of the flue gas is prevented from flowing through the gas passing channel in the hollow structure, and the heat exchange efficiency of the condensation heat exchange structure is improved. In addition, the heat exchange pipe is bent along the direction of the cross section of the shell in a circuitous manner, so that the flowing path of cold water in the heat exchange pipe can be increased, the heat exchange time with the flue gas in the shell can be prolonged, and the waste heat of the flue gas can be fully utilized to improve the heat exchange efficiency.

In one embodiment, the smoke inlet and the side wall of the shell are provided with chamfers.

In one embodiment, the angle of the chamfer is 40-50 °.

In one embodiment, the smoke inlet and the smoke outlet are distributed on different sides with respect to a central axis of the housing.

In one embodiment, the water inlet and the water outlet both protrude to the outside of the housing, and the water inlet and the water outlet are both fixed to a wall of the housing.

In one embodiment, the outer wall of the heat exchange tube is provided with a hydrophobic layer.

In one embodiment, the bottom of the housing has a condensate drain port with a valve or removable sealing cap mounted thereon.

In one embodiment, a gap distributed opposite to the smoke inlet is formed between the head part and the tail part of the heat exchange tube.

In one embodiment, any part of the heat exchange tube has smooth transition.

In one embodiment, the heat exchange tube comprises: a plurality of straight pipes and a plurality of arc pipes which are distributed at intervals;

the extending direction of the straight pipe is the same as that of the shell;

the straight pipes and the arc pipes are alternately distributed, so that the straight pipes and the arc pipes are connected to form the hollow structure.

A gas water heater, comprising: the heating assembly, the fan and the condensation heat exchange structure are arranged on the shell;

the smoke inlet of the condensation heat exchange structure is communicated with the smoke outlet of the fan;

and the water outlet of the condensation heat exchange structure is communicated with the tube side inlet of the heat exchanger of the heating assembly.

According to the gas water heater, smoke discharged by the fan of the gas water heater enters the shell through the smoke inlet of the shell, one part of smoke flows into the air passing gap formed between the heat exchange tube and the inner wall of the shell, cold water close to the outer wall of the heat exchange tube exchanges heat in the process of flowing to the smoke outlet, the other part of smoke flows into the hollow structure formed by the heat exchange tube in a circuitous and bent mode, cold water close to the inner wall of the heat exchange tube exchanges heat in the process of flowing to the smoke outlet, and the cold water heat exchange is guaranteed to be uniform. Because the heat exchange tube is circuitous and bent to form a hollow structure, the resistance of the flue gas flowing through the gas passing gap is the same as the resistance of the gas passing channel in the hollow structure, the uniform distribution of the flue gas is ensured, most of the flue gas is prevented from flowing through the gas passing channel in the hollow structure, and the heat exchange efficiency of the condensation heat exchange structure is improved. In addition, the heat exchange pipe is bent along the direction of the cross section of the shell in a circuitous manner, so that the flowing path of cold water in the heat exchange pipe can be increased, the heat exchange time with the flue gas in the shell can be prolonged, and the waste heat of the flue gas can be fully utilized to improve the heat exchange efficiency.

Drawings

Fig. 1 is a schematic structural diagram of a condensation heat exchange structure according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a heat exchange tube according to an embodiment of the present invention;

FIG. 3 is a schematic view of a flow direction of flue gas in a condensing heat exchange structure according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a heat exchange tube according to another embodiment of the present invention.

Wherein the various reference numbers in the drawings are described below:

100-a housing;

100 a-a smoke inlet;

100 b-a smoke outlet;

100 c-air gap;

100 d-condensate drain;

100 e-chamfering;

200-heat exchange tube;

200 a-a water inlet;

200 b-a water outlet;

200 c-gap;

210-a first straight pipe;

220-a first arced tube;

230-a second straight pipe;

240-second arced tube.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1, fig. 1 is a schematic structural diagram illustrating a condensation heat exchange structure according to an embodiment of the present invention, where the condensation heat exchange structure includes: a shell 100 and a heat exchange pipe 200; a smoke inlet 100a is arranged on the side wall of the casing 100, and a smoke outlet 100b positioned above the smoke inlet 100a is also arranged on the wall of the casing 100; the heat exchange tube 200 is bent and meandered along the cross section of the casing 100 to form a hollow structure (see fig. 2 and 4), and an air gap 200c is formed between the heat exchange tube and the inner wall of the casing 100, and a water inlet 200a and a water outlet 200b are respectively formed on the head and the tail of the heat exchange tube 200.

As an example, the housing 100 may be a cylindrical housing or a rectangular parallelepiped housing, or the like.

As an example, the smoke inlet 100a and the smoke outlet 100b may be welded to the housing 100.

As an example, the shell 100 and the heat exchange pipe 200 are made of stainless steel.

The condensation heat exchange structure can be applied to a gas water heater, smoke discharged by a fan of the gas water heater enters the casing 100 through the smoke inlet 100a of the casing 100, wherein as shown in fig. 3, a part of the smoke flows into the air passing gap 200c formed between the heat exchange tube 200 and the inner wall of the casing 100, and exchanges heat with cold water close to the outer wall of the heat exchange tube 200 in the process of flowing to the smoke outlet 100b, and the other part of the smoke flows into the hollow structure formed by the heat exchange tube 200 by winding and bending, and exchanges heat with cold water close to the inner wall of the heat exchange tube 200 in the process of flowing to the smoke outlet 100b, so that the uniform heat exchange of the cold water is ensured. Because the heat exchange tube 200 is circuitous and bent to form a hollow structure, the resistance that the flue gas flows through the gas passing gap 200c is the same as the resistance that the gas passing channel in the hollow structure flows through, the flue gas is ensured to be uniformly distributed, most flue gas is prevented from flowing through the gas passing channel in the hollow structure, and the heat exchange efficiency of the condensation heat exchange structure is improved. In addition, the heat exchange tube 200 is bent along the cross section of the shell 100, so that the flow path of cold water in the heat exchange tube 200 can be increased, the heat exchange time with the flue gas in the shell 100 can be prolonged, and the waste heat of the flue gas can be fully utilized to improve the heat exchange efficiency.

In some embodiments of the present invention, as shown in fig. 1, the smoke inlet 100a has a chamfer 100e between it and the sidewall of the housing 100. The chamfer 100e can play a role in guiding flue gas and also can slow down the flow velocity of the flue gas, so that the heat exchange between the flue gas and cold water in the heat exchange tube 200 is more sufficient, and the heat exchange efficiency of the flue gas is further improved.

Specifically, in some embodiments of the present invention, the angle of the chamfer 100e is 40 ° to 50 °, for example, 40 °, 41 °, 42 °, 43 °, 44 °, 45 °, 46 °, 47 °, 48 °, 49 °, 50 °, and the like.

In some embodiments of the present invention, as shown in FIG. 1, the smoke inlet 100a and the smoke outlet 100b are distributed on different sides with respect to a central axis of the housing 100. Thus, the flue gas can be ensured to flow through any part of the heat exchange tube 200, especially the part far away from the smoke inlet 100a, so that the heat exchange between the flue gas and the cold water in the heat exchange tube 200 is more sufficient.

Alternatively, the smoke outlet 100b may be opened on the top of the case 100 as shown in fig. 1.

In some embodiments of the present invention, as shown in fig. 1, both the inlet port 200a and the outlet port 200b protrude to the outside of the case 100, and both the inlet port 200a and the outlet port 200b are fixed on the wall of the case 100. Thus, it is possible to facilitate the communication of the water inlets 200a and the water outlets 200b with the external pipeline, and it is also not necessary to install a bracket for fixing the heat exchange pipe 200 in the case 100.

Alternatively, the water inlet 200a and the water outlet 200b may be fixed to the wall of the housing 100 by welding.

In some embodiments of the present invention, a hydrophobic layer is disposed on the outer wall of the heat exchange pipe 200. The hydrophobic layer can prevent condensed water from attaching to the heat exchange tube 200 under the condition that the condensed water is generated on the tube wall when the flue gas exchanges heat with the heat exchange tube 200 due to high humidity of the external environment, so that the heat exchange tube 200 can be prevented from being corroded, and the heat exchange effect can be prevented from being influenced by condensation and film formation on the heat exchange tube 200.

Optionally, the hydrophobic layer is disposed on the outer wall of the heat exchange tube 200 by painting. Wherein, the coating used for the hydrophobic layer can comprise: A. a component B; the component A comprises the following components in parts by mass: 90-98 parts of modified acrylic resin, 1-2 parts of peroxide, 0.5-1 part of fumed silica and 0.5-1 part of dispersant; the component B comprises the following components in parts by mass: 5-10 parts of a curing accelerator, 0.1-1 part of modified super-hydrophobic silicon dioxide and 90-95 parts of a solvent; A. the mass ratio of the component B is 10-20: 1.

further, in some embodiments of the present invention, as shown in fig. 1, the bottom of the housing 100 has a condensate discharge port 100d, and a valve or a removable sealing cover is mounted on the condensate discharge port 100 d. Therefore, a large amount of condensed water can be prevented from being accumulated in the casing 100, the casing 100 can be prevented from being corroded by the condensed water, and the heat exchange efficiency of the flue gas can be prevented from being influenced.

Alternatively, the valve may be a mechanical valve, and the user may open the valve at intervals to perform the drain operation. Of course, the valve may also be an electromagnetic valve or an electric valve electrically connected to an electric controller of the gas water heater, and the electric controller may open the valve at intervals according to the setting of a user to perform a water discharge operation.

As shown in fig. 2 and 4, in some embodiments of the present invention, the heat exchange tube 200 has a gap 200c between the head and the tail thereof, which is distributed opposite to the air inlet. The gap 200c can ensure that a part of the flue gas smoothly enters the hollow structure formed by the heat exchange tube 200 by circuitous bending.

In some embodiments of the present invention, the transition is smooth at any position of the heat exchange pipe 200, so that the flow resistance of cold water in the heat exchange pipe 200 can be reduced.

In some embodiments of the present invention, the heat exchange pipe 200 comprises: a plurality of straight pipes and a plurality of arc pipes which are distributed at intervals; the extending direction of the straight pipe is the same as the extending direction of the housing 100; the straight pipes and the arc pipes are alternately distributed, so that the straight pipes and the arc pipes are connected to form a hollow structure.

Specifically, regarding the structure of the heat exchange tube 200 of the above-described structure, the present invention gives two examples:

as shown in fig. 4, the heat exchange pipe 200 of the (1) example includes: a plurality of first straight pipes 210 and a plurality of first arc pipes 220 which are distributed at intervals along the circumferential direction of the shell 100; the extending direction of each first straight tube 210 is the same as the extending direction of the housing 100; one end of any inner first straight pipe 210 is communicated with an adjacent first straight pipe 210 through a corresponding first arc-shaped pipe 220, and the other end of any inner first straight pipe 210 is communicated with another adjacent first straight pipe 210 through a corresponding first arc-shaped pipe 220; the water inlet 200a is disposed on one of the outermost first straight pipes 210, and the water outlet 200b is disposed on the other outermost first straight pipe 210. The first straight tube 210 at the head and the first straight tube 210 at the tail are referred to as outermost first straight tubes 210, and the remaining first straight tubes 210 are referred to as inner first straight tubes 210. The heat exchange tube 200 is simple in structure.

Alternatively, the first straight tube 210 and the first arc-shaped tube 220 are integrally formed, and during processing, one deformable and heat-exchangeable straight tube can be folded into the heat exchange tube 200 with the above structure in a deformation manner.

Optionally, the transition at the junction between the first straight tube 210 and the corresponding first arced tube 220 is gradual.

As shown in fig. 2, the heat exchange pipe 200 of the (2) example includes: a plurality of first straight pipes 210, a plurality of first arc-shaped pipes 220, a second straight pipe 230 and a second arc-shaped pipe 240 which are distributed at intervals along the circumferential direction of the shell 100 and are positioned in a space surrounded by the plurality of first straight pipes 210; the extending direction of each of the first straight pipe 210 and the second straight pipe 230 is the same as the extending direction of the casing 100; one end of any inner first straight pipe 210 is communicated with an adjacent first straight pipe 210 through a corresponding first arc-shaped pipe 220, and the other end of any inner first straight pipe 210 is communicated with another adjacent first straight pipe 210 through a corresponding first arc-shaped pipe 220; one end of the second straight pipe 230 is communicated with a first straight pipe 210 at the outermost side through a second arc-shaped pipe 240; the water inlet 200a is disposed on the second straight pipe 230 and the water outlet 200b is disposed on the outermost another first straight pipe 210, or the water inlet 200a is disposed on the outermost another first straight pipe 210 and the water outlet 200b is disposed on the second straight pipe 230. The heat exchange pipe 200 of such a structure can increase the flow time of cold water in the heat exchange pipe 200.

Optionally, the first straight tube 210 and the corresponding first arc-shaped tube 220, the first straight tube 210 and the second arc-shaped tube 240, and the first straight tube 210 and the second arc-shaped tube 240 may be integrally formed, and during processing, one deformable and heat-exchangeable straight tube may be folded into the heat exchange tube 200 with the above structure in a deformation manner.

Optionally, the transition at the connection between the first straight tube 210 and the corresponding first arced tube 220, between the first straight tube 210 and the second arced tube 240, and between the first straight tube 210 and the second arced tube 240 is gradual.

Another embodiment of the present invention provides a gas water heater, including: the heating assembly, the fan and the condensation heat exchange structure are arranged on the shell; the smoke inlet 100a of the condensation heat exchange structure is communicated with the smoke outlet of the fan; the water outlet 200b of the condensation heat exchange structure is communicated with the tube side inlet of the heat exchanger of the heating assembly.

As an example, the heating assembly includes: the heat exchanger is used for conveying a fire exhaust pipe and an air inlet pipe of high-temperature flue gas to the shell pass of the heat exchanger; a tube pass inlet and a tube pass outlet of the heat exchanger are respectively communicated with a cold water pipe and a hot water pipe; the fire grate is provided with an ignition needle and a fire detection needle; the gas inlet pipe is communicated with the fire grate through a sectional valve, and is also provided with a gas proportional valve electrically connected with the controller so as to adjust the flow proportion of gas and air and further adjust the combustion power; the fan is used for providing air required by fire row combustion and discharging flue gas after combustion.

As an example, two connected pipelines in a gas water heater can be communicated through a flange.

In the gas water heater as described above, the flue gas discharged by the fan of the gas water heater enters the casing 100 through the smoke inlet 100a of the casing 100, wherein as shown in fig. 3, a part of the flue gas flows into the air passing gap 200c formed between the heat exchange tube 200 and the inner wall of the casing 100, and exchanges heat with the cold water near the outer wall of the heat exchange tube 200 in the process of flowing to the smoke outlet 100b, and the other part of the flue gas flows into the hollow structure formed by the heat exchange tube 200 by winding and bending, and exchanges heat with the cold water near the inner wall of the heat exchange tube 200 in the process of flowing to the smoke outlet 100b, thereby ensuring uniform heat exchange of the cold water. Because the heat exchange tube 200 is circuitous and bent to form a hollow structure, the resistance that the flue gas flows through the gas passing gap 200c is the same as the resistance that the gas passing channel in the hollow structure flows through, the flue gas is ensured to be uniformly distributed, most flue gas is prevented from flowing through the gas passing channel in the hollow structure, and the heat exchange efficiency of the condensation heat exchange structure is improved. In addition, the heat exchange tube 200 is bent along the cross section of the shell 100, so that the flow path of cold water in the heat exchange tube 200 can be increased, the heat exchange time with the flue gas in the shell 100 can be prolonged, and the waste heat of the flue gas can be fully utilized to improve the heat exchange efficiency.

As shown in fig. 2 and 4, in some embodiments of the present invention, the heat exchange tube 200 has a gap 200c between the head and the tail thereof, which is distributed opposite to the smoke inlet 100 a. The gap 200c can ensure that a part of the flue gas smoothly enters the hollow structure formed by the heat exchange tube 200 by circuitous bending.

In some embodiments of the present invention, the transition is smooth at any position of the heat exchange pipe 200, so that the flow resistance of cold water in the heat exchange pipe 200 can be reduced. It is understood that when the heat exchange pipe 200 is the structure provided in the above (1) example, the transition of the connection between the first straight pipe 210 and the corresponding first arc pipe 220 is gentle; when the heat exchange tube 200 has the structure provided by the above-mentioned example (2), the transition at the connection points between the first straight tube 210 and the corresponding first arc-shaped tube 220, between the first straight tube 210 and the second arc-shaped tube 240, and between the first straight tube 210 and the second arc-shaped tube 240 is gradual.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A condensation heat exchange structure, comprising: a shell (100) and a heat exchange pipe (200);

a smoke inlet (100a) is formed in the side wall of the shell (100), and a smoke outlet (100b) located above the smoke inlet (100a) is further formed in the wall of the shell (100);

the heat exchange tube (200) is circuitously bent along the cross section of the shell (100) to form a hollow structure, an air gap (200c) is formed between the heat exchange tube and the inner wall of the shell (100), and a water inlet (200a) and a water outlet (200b) are respectively arranged on the head and the tail of the heat exchange tube (200).

2. The condensation heat exchange structure according to claim 1, wherein a chamfer (100e) is provided between the smoke inlet (100a) and the side wall of the shell (100).

3. The condensation heat exchange structure according to claim 2, wherein the angle of the chamfer (100e) is 40 ° to 50 °.

4. The condensation heat exchange structure according to claim 1, wherein the smoke inlet (100a) and the smoke outlet (100b) are distributed on different sides with respect to a central axis of the shell (100).

5. The condensation and heat exchange structure according to claim 1, wherein the water inlet (200a) and the water outlet (200b) are both protruded to the outside of the shell (100), and the water inlet (200a) and the water outlet (200b) are both fixed on the wall of the shell (100).

6. The condensation heat exchange structure according to claim 1, wherein the heat exchange tubes (200) are provided with a hydrophobic layer on their outer wall.

7. The condensation and heat exchange structure according to claim 6, wherein the bottom of the casing (100) has a condensate discharge port (100d), and a valve or a removable sealing cover is mounted on the condensate discharge port (100 d).

8. A condensation and heat exchange structure according to any one of claims 1 to 7, wherein the heat exchange pipe (200) has a gap (200c) between the head and the tail thereof, which is distributed opposite to the smoke inlet (100 a).

9. The condensation and heat exchange structure according to any one of claims 1 to 7, wherein any part of the heat exchange pipe (200) is transited smoothly.

10. A condensation and heat exchange structure according to any one of claims 1 to 7, wherein the heat exchange tube (200) comprises: a plurality of straight pipes and a plurality of arc pipes which are distributed at intervals;

the extending direction of the straight pipe is the same as the extending direction of the shell (100);

11. A gas water heater, comprising: a heating assembly, a fan, and the condensing heat exchange structure of any one of claims 1-10;

a smoke inlet (100a) of the condensation heat exchange structure is communicated with a smoke outlet of the fan;

and a water outlet (200b) of the condensation heat exchange structure is communicated with a tube side inlet of a heat exchanger of the heating assembly.