CN201615608U - Condensing gas boiler - Google Patents

Abstract

The utility model relates to a condensing gas boiler, which belongs to the technical field of heat exchange facilities. The product is mainly composed of a burner and a heat exchange device with flue gas and water flow channels. The heat exchange device includes horizontal heat exchangers and V-shaped heat exchangers connected in series; The first group of water pipes in the channel has a cylindrical combustion chamber in the middle; a burner is installed at one end of the cylindrical combustion chamber, and the flue gas passes through the horizontal heat exchanger and enters the V-shaped smoke of the V-shaped heat exchanger through the downward through hole. Air flow channel; the V-shaped smoke flow channel is equipped with a second set of water pipes distributed at intervals to form a circuitous flow channel; the water flow first passes through the second set of water pipes, then through the first set of water pipes, and from the combustion chamber, and through the V-shaped smoke The flue gas in the flow channel forms a reverse heat exchange. The utility model has sufficient heat exchange, can maintain the flow velocity of the flue gas after cooling to ensure the heat exchange efficiency, has a reasonable structure, and occupies a small area.

Description

Condensing gas boiler

technical field

The utility model relates to a gas boiler, in particular to a condensing gas boiler, which belongs to the technical field of heat exchange facilities.

Background technique

As far as the applicant knows, the typical structure of the existing condensing heat exchanger for gas water heaters is disclosed in the Chinese utility model patent with the application number 200820052420.4 and the application date of 2008-03-04, which includes a heat exchange chamber, a heat exchange tube, Smoke inlet, smoke exhaust port, cold water inlet, hot water outlet, and condensed water outlet located in the heat exchange chamber. The channel, the inner tube of the heat exchanger and the outer shell of the heat exchanger are respectively connected with the smoke inlet and the smoke exhaust port. The heat exchange tubes are arranged in the heat exchange chamber in the form of spiral tubes. heat exchange tubes in contact. When working, the flue gas moves along the annular channel and evenly contacts the spiral heat exchange tubes arranged in it. Such products generally have the following disadvantages: 1) There is only one-stage heat exchange, and the heat exchange is insufficient; 2) When condensed water is generated, the burner is easily extinguished; the condensed water cannot be discharged, and it is easy to form a water film on the surface of the copper tube, hindering the exchange 3) a large amount of copper pipes and a large floor area are required.

Utility model content

The purpose of this utility model is mainly to propose a condensing gas boiler with sufficient heat exchange, compact structure and small footprint in view of the shortcomings of the above-mentioned prior art.

The further object of the utility model is to propose a condensing gas boiler that can discharge condensed water in time to ensure high-efficiency heat exchange.

In order to achieve the above primary purpose, the condensing gas boiler of the present utility model is mainly composed of a burner and a heat exchange device with flue gas and water flow channels. The heat exchanger and the lower V-shaped heat exchanger; the circumference of the annular horizontal heat exchanger is distributed with a first group of water pipes forming a circuitous flow channel, and the middle part is a cylindrical combustion chamber; a burner is installed at one end of the cylindrical combustion chamber , the flue gas passes through the horizontal heat exchanger and passes through the V-shaped flue flow channel of the V-shaped heat exchanger facing downward; the V-shaped flue gas flow channel is equipped with a second group of water pipes that are distributed at intervals to form a circuitous flow channel; The water flows first through the second set of water pipes and then through the first set of water pipes to form a reverse heat exchange with the flue gas originating from the combustion chamber and passing through the V-shaped flue flow channel.

Because the flue gas from the burner in the utility model undergoes two-stage heat exchange successively, the heat exchange is more sufficient. Moreover, since the first-stage heat exchanger is ring-shaped and the second-stage heat exchanger is a V-shaped structure with a large top and a small bottom, the heat exchange between the first stage and the cylindrical combustion chamber is more sufficient, and the second stage can The flow rate of flue gas after cooling is maintained to ensure heat exchange efficiency; as a result, sufficient heat exchange is further realized. In addition, since the secondary heat exchanger is arranged up and down, the structure is reasonable and the floor space is small.

Experiments have shown that most of the flue gas condensation process occurs in the upper half of the second-stage heat exchanger, especially in the case of long-term operation and low inlet water temperature, the amount of condensed water is often large, if the condensed water drops on the bottom On the water pipes, a water film will be formed, which not only seriously hinders the heat exchange effect between the flue gas and water, but also accelerates the corrosion of the water pipes. Therefore, in order to achieve a further purpose, the middle part of the V-shaped flue gas flow channel is provided with condensed water distribution plates inclined to both sides. In this way, the condensed water generated by the flue gas can smoothly flow along the splitter plate to both sides for discharge, thereby preventing the formation of a water film on the water pipe, and while weakening the corrosion of the water pipe by the condensed water, the flue gas can fully contact the water pipe , which increases the heat transfer coefficient of the second-stage heat exchanger, absorbs the heat in the flue gas more effectively, and further improves the heat transfer efficiency.

Description of drawings

Below in conjunction with accompanying drawing, the utility model is further described.

Fig. 1 is a structural schematic diagram of Embodiment 1 of the utility model.

FIG. 2 is a side view of FIG. 1 .

FIG. 3 is one of the three-dimensional cross-sectional structural schematic diagrams of the embodiment in FIG. 1 .

FIG. 4 is the second perspective view of the structure of the embodiment in FIG. 1 .

Fig. 5 is a schematic diagram of the three-dimensional structure of the second embodiment of the utility model.

FIG. 6 is a schematic diagram of a two-dimensional structure of the embodiment in FIG. 5 .

Detailed ways

Embodiment one

The condensing gas boiler of this preferred embodiment is shown in Figures 1 to 4, and is mainly composed of a burner (not shown in the figure) and a heat exchange device with flue gas and water flow channels. The heat exchange device includes an upper annular horizontal heat exchanger 1 and a lower V-shaped heat exchanger 2 located in the casing 3 and connected in series. The circumference of the annular horizontal heat exchanger 1 is distributed with a first group of water pipes forming a roundabout flow channel, and the middle part is a cylindrical combustion chamber 1-1. A burner is installed at the front end of the cylindrical combustion chamber 1-1, and the V-shaped flue gas flow channel 2 of the V-shaped heat exchanger 2 passes through the exhaust holes 4-1 facing downwards at both ends of the mesh plate 4 separating the two heat exchangers. -1 connectivity.

The V-shaped flue gas flow channel 2-1 is equipped with a second group of water pipes that are distributed at intervals to form a circuitous flow channel. , second, third, fourth, and fifth rows of pipes P1, P2, P3, P4, and P5. Wherein, the rear ends of the fourth and fifth row pipes communicate with the water inlet 8 at the rear V-shaped water seal head 2-3, and their front ends connect with the third row pipe P3 at the front V-shaped water seal head 2-3'. Front-end connectivity. The rear end of the third row pipe P3 communicates with the rear end of the second row pipe P2 at the rear V-shaped water seal head 2-3. The front end of the second row of pipes P2 communicates with the front end of the first row of pipes P1 at the front V-shaped water seal head 2-3' place. The rear end of the first row pipe P1 communicates with the lower end of the C-shaped communication pipe 5 at the rear V-shaped water seal head 2-3.

The first group of water pipes is divided into the first, second and third section pipes PA, PB and PC by three radial partitions 1-2 uniformly distributed along the circumference. The rear end of the first section pipe PA communicates with the upper end of the C-shaped communication pipe 5 at the rear annular water seal head 1-3. The front ends of the first section pipe PA and the second section pipe PB are connected at the front annular water seal head 1-3', and the rear ends of the second section pipe PB and the third section pipe PC are connected at the rear annular water seal head 1-3 are connected. The front end of the third section pipe PC communicates with the water outlet 6 at the front annular water seal head 1-3'.

The above second group of water pipes and the first group of water pipes are all made of copper finned tubes.

When working, the water flow detours from the water inlet first through the second set of water pipes, then through the first set of water pipes, and finally outputs from the water outlet, while the high-temperature flue gas generated by the burner passes through the copper fins of the first set of water pipes from the combustion chamber. , and then through the exhaust holes on the screen, through the V-shaped smoke flow channel, through the copper fins of the second group of water pipes, and finally discharged from the smoke exhaust port 7 on one side. Since the direction of the water flow is opposite to that of the flue gas, an efficient counter-current heat exchange is formed.

In other words, in the first-stage heat exchanger, under the action of the M-shaped flue gas baffle between the copper tubes, the flow resistance of the flue gas increases, and the contact with the copper tube is sufficient, and the flue gas is extruded from the gap between the fins. At the same time, it has two heat exchange methods of radiation and convection. The heat can be fully transferred to the water flowing in the copper tube, and the temperature of the flue gas is lowered. After that, it enters the second-stage V-shaped heat exchange through the mesh structure between the two heat exchangers. In the heat exchanger, since the temperature of the water entering the copper tube of the secondary heat exchanger is relatively low, most of the remaining heat in the flue gas is also fully absorbed by the water, and finally the hot water flows out from the top of the upper primary heat exchanger, while the low temperature The low-emission flue gas is discharged from the lower stage heat exchanger. The whole process is a countercurrent heat exchange process. This kind of countercurrent condensation heat exchange method makes this embodiment have the advantages of using less materials under high load conditions, occupying a small space and High thermal efficiency and other advantages.

In addition, the design of the secondary heat exchanger with the V-shaped tapered structure design in this embodiment takes into account that under the influence of the flue gas baffle between the copper tubes of the first stage heat exchanger, the flow rate of the flue gas entering the secondary heat exchanger becomes slower , the heat transfer efficiency decreases, and the V-shaped tapered structure can make the flow rate of the flue gas increase due to the reduction of the flow area when it flows in it, thereby increasing the convective heat transfer coefficient and making the heat of the flue gas in the secondary heat exchanger Better transfer to the water flowing in the copper pipe. At the same time, the increase of the flue gas flow rate makes it easier to blow off the accumulated condensed water on the copper tube fins, preventing the condensed water from forming a water film on the copper tube and weakening the convective heat transfer effect of the flue gas, improving the heat transfer efficiency and protecting the copper tube. Not corroded. This structure is of great significance to the improvement of heat exchange efficiency.

In order to discharge the condensed water in time, in this embodiment, a condensed water distribution plate 9 inclined to both sides is provided between the third row pipe P3 and the fourth row pipe P4 in the V-shaped flue gas flow channel ( FIG. 1 ). The condensate splitter plate is made of steel plate, welded between two rows of copper tubes, and becomes a whole with the heat exchanger. It is confirmed by experiments and CFD simulation that most of the flue gas condensation process occurs in the upper half of the second-stage heat exchanger, especially when the machine is running for a long time and the inlet water temperature is low, the amount of condensed water is very large. Too much, if the condensed water drops on the copper tube below, it will form a water film, which not only seriously hinders the heat exchange effect between the flue gas and water, but also accelerates the corrosion of the final copper tube. After adding the condensed water distribution plate, the condensed water generated in the flue gas can smoothly flow along the distribution plate to both sides and be discharged through the openings on both sides, which prevents the formation of water film on the copper tube and weakens the impact of condensed water on While the copper tubes corrode, the flue gas can fully contact the copper tubes, which increases the heat transfer coefficient of the rows of copper tubes behind the second stage heat exchanger, absorbs the heat in the flue gas more effectively, and further improves the heat transfer. efficiency. Under the action of this special structure, this embodiment not only ensures that the machine can work normally under large water flow, but also ensures that the heat exchange efficiency of the whole machine is kept at the condensation level.

In short, this embodiment has two-stage copper-fin heat exchanger and premixed combustion system applied to the water heater, the first stage of the two-stage horizontal heat exchanger adopts a ring structure, and the second stage adopts a V-shaped tapered structure. Compared with traditional water heaters, the main features are: 1) Condensing heat exchange, 2) V-shaped heat exchanger with enhanced heat exchange, 3) Condensate distribution plate that can effectively remove condensed water and prevent corrosion, 4) Form two Stage countercurrent heat exchange; etc., so not only can achieve the same load with less material, save a lot of space, but also have higher thermal efficiency and lower emissions of carbon oxides and nitrogen oxides.

Embodiment two

The condensing gas boiler of this embodiment is shown in Figure 5 and Figure 6. The difference from Embodiment 1 is that the horizontal heat exchanger is located on one side of the V-shaped heat The channel is connected; its working principle and main advantages are the same as those in Embodiment 1, and will not be repeated here.

In addition to the above embodiments, the utility model can also have other implementations. All technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the utility model.

Claims (8)

1. A condensing gas boiler, mainly composed of a burner and a heat exchange device with flue gas and water flow channels, characterized in that: the heat exchange device includes horizontal heat exchangers and V-shaped heat exchangers connected in series ; The circumference of the horizontal heat exchanger is distributed with a first group of water pipes forming a roundabout flow channel, and the middle part is a cylindrical combustion chamber; one end of the cylindrical combustion chamber is equipped with a burner, and the flue gas passes through the horizontal heat exchanger And enter the V-shaped flue flow channel of the V-shaped heat exchanger through the downward through hole; the V-shaped flue gas flow channel is equipped with a second set of water pipes that are distributed at intervals to form a circuitous flow path; the water flow first passes through the second set of water pipes , and then pass through the first group of water pipes to form a reverse heat exchange with the flue gas from the combustion chamber and through the V-shaped flue gas flow channel. 2. The condensing gas-fired boiler according to claim 1, characterized in that: the middle part of the V-shaped flue gas flow channel is provided with condensed water distribution plates inclined to both sides. 3. The condensing gas boiler according to claim 1 or 2, characterized in that: the first group of water pipes is divided into the first, second and third zones by three radial partitions uniformly distributed along the circumference section pipe; the rear end of the first section pipe communicates with the upper end of the C-shaped connecting pipe at the rear annular water seal head, and the front ends of the first section pipe and the second section pipe are connected at the front annular water seal head The rear end of the second section pipe and the third section pipe are connected at the rear annular water seal head, and the front end of the third section pipe is connected with the water outlet at the front annular water seal head. 4. The condensing gas boiler according to claim 3, characterized in that: the second group of water pipes is divided into first, second, third and fourth pipes arranged up and down at equal intervals and separated by horizontal partitions. , fifth row of pipes in total; the rear end of the fourth and fifth row pipes communicates with the water inlet at the rear V-shaped water seal head, and the front end communicates with the front end of the third row of pipes at the front V-shaped water seal head The rear end of the third row of pipes communicates with the rear end of the second row of pipes at the rear V-shaped water seal head, and the front end of the second row of pipes connects with the first row of pipes at the front V-shaped water seal head. The front end communicates, and the rear end of the first row pipe communicates with the lower end of the C-shaped communication pipe at the rear V-shaped water seal head. 5. The condensing gas boiler according to claim 4, characterized in that: the horizontal heat exchanger is an annular horizontal heat exchanger located above the V-shaped heat exchanger. 6. The condensing gas boiler according to claim 5, characterized in that: the horizontal heat exchanger is located on one side of the V-shaped heat exchanger, and communicates with each other through a series flue. 7. The condensing gas-fired boiler according to claim 6, characterized in that: condensed water distribution plates inclined to both sides are arranged between the third row of pipes and the fourth row of pipes. 8. The condensing gas-fired boiler according to claim 7, characterized in that: the tubular combustion chamber is separated from the bottom of the V-shaped heat exchanger through the downward row holes at both ends of the mesh plates separating the two heat exchangers. The V-shaped flue flow channels are connected.

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