Gas water heater combustion chamber air flow distribution structure

Abstract

The utility model discloses a gas water heater combustion chamber airflow distribution structure relates to gas water heater combustion system technical field, including the combustion chamber, and the inside bottom plate of combustion chamber is equipped with the reverse buckle type casing, and the casing is surrounded with bottom plate and is formed distribution cavity, the casing upper end surface is equipped with a plurality of integrated gas outlet pipe, and the gas outlet pipe is connected with above fire row one to one correspondence, and distribution cavity is equipped with the gas jet of corresponding gas outlet pipe along the length direction, and the gas jet is connected with the manifold through the gas distribution manifold, and the bottom plate middle part outside is equipped with the fan, and the air outlet of fan communicates distribution cavity, distribution cavity is equipped with trapezoidal shunt flow guide grid, gradient aperture / opening rate's porous flow equalizing plate, longitudinal isolation board and gas outlet pipe pressure compensation ring. The structure realizes airflow even distribution, gas - air full premixing, and promotes the stability of combustion.

Description

Technical Field

[0001] This utility model relates to the technical field of gas water heater combustion systems, and in particular to an airflow distribution structure for a gas water heater combustion chamber. Background Technology

[0002] The combustion performance of forced-draft gas water heaters depends on the precision of the airflow distribution in the combustion chamber and the connection between the gas and the burner. Existing technologies mainly have two limitations: Firstly, the airflow distribution exhibits natural diffusion characteristics. Existing forced-draft water heaters generally employ a structure where a bottom-mounted fan is directly connected to the bottom of the combustion chamber. The fan outlet leads directly to the open space below the burner, without any directional guidance or distribution devices. After being discharged from the fan, the airflow naturally diffuses along the length of the combustion chamber. The side closer to the fan experiences a short airflow path and low resistance, resulting in ample air supply. Conversely, the side farther from the fan suffers from insufficient air due to pressure attenuation during airflow diffusion, directly leading to uneven combustion conditions in the burner.

[0003] Secondly, the gas-burner connection adopts a non-direct connection structure. The gas supply pipe outlet and the burner inlet are only spatially aligned through a 5-15mm gap, without physical connection. This design is essentially a compromise for uneven airflow distribution: the reserved gap provides mixing space for gas and air, but the open structure makes the mixing efficiency significantly affected by airflow differences, and it is prone to airflow crosstalk between adjacent burners. In the long term, vibration will also exacerbate the alignment deviation, further deteriorating combustion stability.

[0004] The aforementioned limitations directly lead to problems such as fluctuating combustion efficiency and insufficient flame stability. Therefore, solving the differences in airflow distribution and optimizing the connection between the gas supply pipe and the burner have become key directions for improving product performance.

[0005] The aforementioned limitations directly lead to problems such as fluctuating combustion efficiency and insufficient flame stability. Utility Model Content

[0006] To address the aforementioned problems, the purpose of this utility model is to provide an airflow distribution structure for the combustion chamber of a gas water heater, which addresses the issues of uneven airflow in the combustion chamber and the tendency for mixing fluctuations, crossflows, and alignment deviations to occur at the connection between the gas supply pipe and the burner, thereby affecting combustion stability.

[0007] The technical solution of this utility model is as follows: A gas water heater combustion chamber airflow distribution structure includes a combustion chamber with an inverted shell on its inner bottom plate. The shell and bottom plate enclose a distribution cavity, creating an independent space where airflow does not leak and mixing does not diffuse. This provides a stable environment for the full premixing of air and gas, avoiding the mixing ratio fluctuations caused by disordered airflow diffusion in traditional open chambers. Multiple gas outlet pipes are spaced apart on the upper surface of the shell, integrally formed with the shell. Above the gas outlet pipes are multiple burners arranged along the length of the combustion chamber. Each gas outlet pipe... Each gas inlet is connected to a corresponding burner inlet, achieving "one burner corresponding to one independent airflow channel." The distribution chamber contains multiple gas nozzles arranged along its length, each corresponding to a gas outlet pipe. The central axis of each gas nozzle and the central axis of its corresponding gas outlet pipe are on the same vertical line. Multiple gas nozzles are connected to a main pipe, which passes through the side wall of the housing and has a connector at its end for connecting to the gas pipeline of the gas water heater, ensuring a stable gas supply. A fan is located on the outer side of the central area of ​​the base plate. This design allows the air delivered by the fan to diffuse evenly from the center of the distribution chamber to both sides, initially reducing the gradient difference of "excessively strong airflow near the fan end and insufficient airflow at the far end," laying the foundation for subsequent airflow adjustment. The fan outlet penetrates the base plate and communicates with the interior of the distribution chamber.

[0008] Furthermore, a flow-diverting grid is provided inside the distribution cavity, above the fan outlet. The flow-diverting grids are equidistantly distributed along the length of the distribution cavity, and the grid spacing is consistent with the spacing of the air outlet pipe. Each grid has a trapezoidal structure that is narrower at the bottom and wider at the top. The core design of this trapezoidal structure is to "guide the airflow to diffuse upward": after the air supplied by the fan enters the grid unit from the bottom, the flow velocity gradually decreases as the trapezoidal cross-section expands, while it diffuses gently to both sides, avoiding the local turbulence caused by the airflow directly impacting the upper components. This initially achieves "uniform distribution of air along the length of the distribution cavity", providing a basis for the precise adjustment of the flow equalization plate in the future. The flow-diverting grids are connected to the inner sidewall of the distribution cavity by bolts.

[0009] Furthermore, a porous flow equalization plate covering the entire cross-section of the distribution chamber is provided above the diversion and guide grid and below the main pipe. It is connected to the inner sidewall of the distribution chamber by bolts, and there is a gap between it and the diversion and guide grid to ensure that the airflow has enough space to stabilize after being diffused by the grid before entering the flow equalization plate. The porous flow equalization plate array is distributed with flow equalization holes, which are circular through holes. The function of the flow equalization plate is to "secondarily calibrate the airflow velocity": the air that has been initially diffused by the diversion and guide grid will eliminate the local velocity difference due to the throttling effect of the holes when passing through the flow equalization holes, so that the airflow flows upward at a uniform speed, avoiding the problem of "fast airflow near the fan end and slow airflow far end", and providing a uniform air environment for the directional injection of gas nozzles.

[0010] Furthermore, the diameter of the flow equalization holes near the air outlet is smaller than that of the flow equalization holes far from the air outlet, and the opening ratio of the flow equalization holes near the air outlet is greater than that of the flow equalization holes far from the air outlet. The principle is "active compensation for pressure difference": the airflow pressure near the air outlet of the fan is higher. By combining "small diameter + high opening ratio", the small diameter is used to increase local airflow resistance, and the high opening ratio is used to ensure the total airflow. On the other hand, the airflow pressure in the area far from the air outlet is lower. By combining "large diameter + low opening ratio", the large diameter is used to reduce airflow resistance, and the low opening ratio is used to avoid excessive local airflow. Ultimately, the airflow pressure and velocity at the outlet end of the entire flow equalization plate are consistent.

[0011] Furthermore, multiple longitudinal isolation plates are provided above the porous flow equalization plate. The longitudinal isolation plates are fixed to the front and rear inner sidewalls of the distribution cavity by welding (consistent with the width direction of the distribution cavity). The longitudinal isolation plates are distributed at intervals along the length direction of the distribution cavity, and each longitudinal isolation plate is located in the middle of two adjacent gas nozzles. That is, two adjacent longitudinal isolation plates and the front and rear sidewalls of the distribution cavity together form a "small mixing area". Each small area corresponds to a gas nozzle and an outlet pipe, avoiding mutual interference of the mixed airflow in adjacent areas. On the other hand, the gap at the upper end ensures the pressure balance between each area, preventing excessive local pressure from causing airflow blockage, while not affecting the full premixing of gas and air in the area.

[0012] Furthermore, each of the air outlet pipes is provided with a pressure compensation ring on the inner side of its air inlet. The diameter of the pressure compensation ring near the air outlet is smaller than that of the one farther away from the air outlet. After multiple layers of adjustment by the diversion and flow guide grille, the perforated flow equalization plate, and the longitudinal isolation plate, the air outlet pipe far from the fan may still have slightly lower pressure due to the long airflow path. By increasing the diameter of the far-end compensation ring, the resistance of the airflow entering the air outlet pipe is reduced, ensuring that the air inlet pressure deviation of all air outlet pipes is controlled within a reasonable range.

[0013] Furthermore, multiple gas nozzles are connected to the main pipe via gas distribution manifolds. The injection direction of each gas nozzle is 45° upward. This angle design makes the gas injection direction form an angle with the upward airflow directed by the flow equalization plate, promoting the formation of turbulence during the collision of gas and air, and greatly improving the mixing uniformity. The axis of each gas nozzle is on the same straight line as the axis of the corresponding gas outlet pipe.

[0014] The beneficial effects of this utility model are as follows: 1. This utility model optimizes the core operating conditions of the combustion system from the root by coordinating the entire process of "airflow regulation - gas-fuel mixing - burner gas supply": with the closed distribution chamber as the basic carrier, combined with the fan, multi-stage airflow regulation components, regional isolation structure and directional injection design, it realizes the full-chain controllability of "uniform air diffusion → precise gas matching → stable delivery of mixed airflow to the burner", which ultimately significantly improves the combustion efficiency and flame stability of the gas water heater.

[0015] 2. This utility model uses a "central fan + diversion and guide grid + porous flow equalization plate" to form the core chain of airflow regulation: the central fan diffuses air from the middle of the distribution chamber to both sides, initially weakening the natural gas flow gradient of "strong near the fan end and weak far end"; the trapezoidal diversion and guide grid further guides the airflow to diffuse smoothly, avoiding local turbulence caused by airflow impact; the porous flow equalization plate actively compensates for the airflow pressure difference in different areas through the differentiated design of "small aperture near the air outlet + high opening ratio, large aperture at the far end + low opening ratio", ultimately achieving consistent airflow pressure and velocity in the distribution chamber, providing a uniform air foundation for gas-fuel mixing.

[0016] 3. This utility model divides the distribution chamber into multiple independent small mixing areas by using a longitudinal isolation plate (each area corresponds to a gas nozzle and a gas outlet pipe), blocking the cross-interference of airflow between adjacent areas; in conjunction with the gas nozzle "slanting upward at 45°" (forming an angle with the upward airflow directed by the multi-hole flow equalization plate, promoting airflow collision and forming turbulence), it ensures that the gas and air are fully mixed in the dedicated area, and the mixing ratio is stable and controllable. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model.

[0018] Figure 2 This is a schematic diagram of the installation of the fan, distribution chamber, and burner of this utility model.

[0019] Figure 3 This is a schematic diagram of the disassembly of the distribution cavity of this utility model.

[0020] Figure 4 This is a schematic diagram of the installation of the distribution cavity of this utility model.

[0021] Reference numerals in the attached drawings: 1. Combustion chamber; 1-1. Base plate; 2. Shell; 2-1. Gas outlet pipe; 3. Burner; 4. Main pipe; 4-1. Gas nozzle; 4-2. Gas distribution manifold; 5. Fan; 6. Flow divider grille; 7. Perforated flow equalization plate; 8. Longitudinal baffle plate. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0023] like Figures 1 to 4 As shown, a gas water heater combustion chamber airflow distribution structure includes a combustion chamber 1. An inverted shell 2 is provided on the inner bottom plate 1-1 of the combustion chamber 1. The shell 2 and the bottom plate 1-1 enclose a distribution cavity, creating an independent space where "airflow does not leak out and mixing does not diffuse". This provides a stable environment for the full premixing of air and gas, avoiding the mixing ratio fluctuation caused by the disorderly diffusion of airflow in traditional open chambers.

[0024] Multiple exhaust pipes 2-1 are spaced apart on the upper end face of the shell 2. The exhaust pipes 2-1 are integrally formed with the shell 2. Multiple burners 3 are arranged along the length of the combustion chamber 1 above the exhaust pipes 2-1. The exhaust port of each exhaust pipe 2-1 is connected to the air inlet of the corresponding burner 3, so that "one burner corresponds to one independent airflow channel".

[0025] The distribution chamber is equipped with multiple gas nozzles 4-1 arranged along its length. Each gas nozzle 4-1 corresponds to a gas outlet pipe 2-1. The central axis of each gas nozzle 4-1 is on the same vertical line as the central axis of the corresponding gas outlet pipe 2-1. The multiple gas nozzles 4-1 are connected to a main pipe 4. The main pipe 4 passes through the side wall of the shell 2 and has a connector at its end for connecting to the gas pipeline of the gas water heater to achieve a stable gas supply.

[0026] A fan 5 is installed on the outer side of the central area of ​​the base plate 1-1. This position is designed so that the air delivered by the fan 5 can be evenly diffused from the center of the distribution cavity to both sides, initially reducing the gradient difference of "excessive airflow near the fan end and insufficient airflow far end", laying the foundation for subsequent airflow adjustment. The air outlet of the fan 5 penetrates the base plate 1-1 and is connected to the inside of the distribution cavity.

[0027] Furthermore, a diversion and flow guiding grille 6 is provided inside the distribution cavity, above the air outlet of the fan 5. The diversion and flow guiding grille 6 is equidistantly distributed along the length of the distribution cavity, and the grille spacing is consistent with the spacing of the air outlet pipe 2-1. Each grille has a trapezoidal structure that is narrow at the bottom and wide at the top. The core design of this trapezoidal structure is to "guide the airflow to diffuse upward": after the air supplied by the fan 5 enters the grille unit from the bottom, the flow velocity gradually decreases as the trapezoidal cross section expands, while it diffuses gently to both sides, avoiding the local turbulence caused by the airflow directly impacting the upper components. This initially achieves "uniform distribution of air along the length of the distribution cavity", providing a basis for the precise adjustment of the flow equalization plate in the future. The diversion and flow guiding grille 6 is connected to the inner side wall of the distribution cavity by bolts.

[0028] Furthermore, a porous flow equalization plate 7 covering the entire cross-section of the distribution chamber is provided above the diversion and guide grid 6 and below the main pipe 4. It is connected to the inner sidewall of the distribution chamber by bolts, and there is a gap between it and the diversion and guide grid 6 to ensure that the airflow has enough space to stabilize after being diffused by the grid before entering the porous flow equalization plate 7. The porous flow equalization plate 7 has an array of flow equalization holes, which are circular through holes. The function of the flow equalization plate is to "secondarily calibrate the airflow velocity": the air that has been initially diffused by the diversion and guide grid 6 will eliminate the local velocity difference due to the throttling effect of the holes when passing through the flow equalization holes, so that the airflow flows upward at a uniform speed, avoiding the problem of "fast airflow near the fan end and slow airflow far end", and providing a uniform air environment for the directional injection of the gas nozzle 4-1.

[0029] Furthermore, the diameter of the flow equalization holes near the air outlet of fan 5 is smaller than that of the flow equalization holes far from the air outlet, and the opening ratio of the flow equalization holes near the air outlet of fan 5 is greater than that of the flow equalization holes far from the air outlet. The principle is "active compensation for pressure difference": the airflow pressure near the air outlet of fan 5 is higher. By combining "small diameter + high opening ratio", the small diameter is used to increase local airflow resistance, and the high opening ratio is used to ensure the total airflow. On the other hand, the airflow pressure in the area far from the air outlet is lower. By combining "large diameter + low opening ratio", the large diameter is used to reduce airflow resistance, and the low opening ratio is used to avoid excessive local airflow. In the end, the airflow pressure and velocity at the outlet end of the entire porous flow equalization plate 7 are consistent.

[0030] Furthermore, multiple longitudinal isolation plates 8 are provided above the porous flow equalization plate 7. The longitudinal isolation plates 8 are fixed to the front and rear inner walls of the distribution cavity by welding (consistent with the width direction of the distribution cavity). The longitudinal isolation plates 8 are distributed at intervals along the length direction of the distribution cavity, and each longitudinal isolation plate 8 is located in the middle of two adjacent gas nozzles 4-1. That is, two adjacent longitudinal isolation plates 8 and the front and rear walls of the distribution cavity together form a "small mixing area". Each small area corresponds to a gas nozzle 4-1 and an outlet pipe 2-1, avoiding mutual interference of the mixed airflow in adjacent areas. On the other hand, the gap at the upper end ensures the pressure balance between each area, preventing excessive local pressure from causing airflow blockage, while not affecting the full premixing of gas and air in the area.

[0031] Furthermore, each air outlet pipe 2-1 has a pressure compensation ring inside its air inlet. The diameter of the pressure compensation ring near the air outlet of the fan 5 is smaller than that of the one farther away from the air outlet. After multiple adjustments by the diversion and flow guide grille 6, the porous flow equalization plate 7, and the longitudinal isolation plate 8, the air outlet pipe 2-1 farther away from the fan 5 may still have slightly lower pressure due to the long airflow path. By increasing the diameter of the compensation ring at the far end, the resistance of the airflow entering the air outlet pipe 2-1 is reduced, ensuring that the air inlet pressure deviation of all air outlet pipes 2-1 is controlled within a reasonable range.

[0032] Furthermore, multiple gas nozzles 4-1 are connected to the main pipe 4 via gas distribution manifolds 4-2. The injection direction of each gas nozzle 4-1 is 45° upward. This angle design makes the gas injection direction form an angle with the upward airflow guided by the porous flow equalization plate 7, which promotes the formation of turbulence during the collision between gas and air and greatly improves the mixing uniformity. The axis of each gas nozzle 4-1 is on the same straight line as the axis of the corresponding gas outlet pipe 2-1.

[0033] Working principle of this utility model: 1. Air homogenization and delivery: The outer fan 5 in the middle sends air into the distribution chamber. The airflow diffuses from the middle of the chamber to both sides, initially weakening the airflow gradient. It is first guided by the trapezoidal diversion grid 6 to diffuse smoothly (first-stage homogenization), and then actively compensates for the pressure difference by the porous flow equalization plate 7 with gradient aperture / opening ratio (second-stage homogenization). Finally, the air is discharged in a state with consistent pressure and flow rate.

[0034] 2. Gas injection and mixing: Gas is distributed to each gas nozzle 4-1 (corresponding to the gas outlet pipe 2-1) via the main pipe 4 and the distribution manifold 4-2. The nozzles are injected at an angle of 45° upwards, colliding with the air discharged by the porous flow equalization plate 7 to form turbulence, which improves the uniformity of gas-fuel mixing. The nozzles and the gas outlet pipe 2-1 are collinear to ensure directional airflow delivery.

[0035] 3. Premixed Stable Control: The longitudinal isolation plate 8 divides the distribution chamber into independent small mixing areas (to prevent adjacent airflow from crossing). The gap at the upper end of the plate balances the air pressure in each area, avoids blockage, and ensures stable premixing of gas and fuel.

[0036] 4. Pressure calibration and ignition delivery: When the premixed airflow enters the outlet pipe 2-1, the pressure compensation ring (smaller pressure near the outlet and larger pressure far from the outlet) cancels out the pressure loss at the far end, ensuring that the pressure of each outlet pipe 2-1 is consistent, and finally accurately delivered to the corresponding burner 3 to achieve stable combustion.

[0037] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A gas water heater combustion chamber airflow distribution structure, comprising a combustion chamber, characterized in that, The combustion chamber has an inverted shell on its inner bottom plate, and the shell and the bottom plate together form a distribution cavity. The upper end face of the housing is provided with multiple air outlet pipes at intervals, and above the air outlet pipes are multiple burners arranged along the length of the combustion chamber. The air outlet of each air outlet pipe is connected to the air inlet of the corresponding burner. The distribution chamber is provided with multiple gas nozzles arranged along its length, each gas nozzle corresponding to a gas outlet pipe. The multiple gas nozzles are connected to a main pipe, which passes through the side wall of the housing and has a connector at its end. A fan is provided on the outer side of the middle part of the base plate, and the air outlet of the fan penetrates through the base plate and communicates with the inside of the distribution chamber.

2. The gas water heater combustion chamber airflow distribution structure according to claim 1, characterized in that, Inside the distribution chamber, above the air outlet of the fan, there is a diversion and flow guiding grille. The diversion and flow guiding grilles are equidistantly distributed along the length of the distribution chamber. The grille spacing is the same as the air outlet pipe spacing. Each grille has a trapezoidal structure that is narrow at the bottom and wide at the top.

3. The gas water heater combustion chamber airflow distribution structure according to claim 2, characterized in that, Above the diversion and guiding grid and below the main pipe, there is a porous flow equalization plate covering the entire cross-section of the distribution cavity, and the porous flow equalization plate array has flow equalization holes distributed in it.

4. The gas water heater combustion chamber airflow distribution structure according to claim 3, characterized in that, The diameter of the flow equalization holes near the air outlet is smaller than that of the flow equalization holes far from the air outlet, and the opening ratio of the flow equalization holes near the air outlet is greater than that of the flow equalization holes far from the air outlet.

5. The gas water heater combustion chamber airflow distribution structure according to claim 3, characterized in that, Above the porous flow equalization plate are multiple longitudinal isolation plates, which are spaced apart along the length of the distribution cavity. Each longitudinal isolation plate corresponds to one of the gas nozzles, and a gap is left between the upper end of the longitudinal isolation plate and the top surface of the distribution cavity.

6. The gas water heater combustion chamber airflow distribution structure according to claim 1, characterized in that, Each of the air outlet pipes has a pressure compensation ring on the inside of its air inlet, with the diameter of the pressure compensation ring closer to the air outlet being smaller than that of the ring farther away from the air outlet.

7. The gas water heater combustion chamber airflow distribution structure according to claim 1, characterized in that, Multiple gas nozzles are connected to the main pipe via gas distribution manifolds. The injection direction of each gas nozzle is 45° upward, and the axis of each gas nozzle is on the same straight line as the axis of the corresponding gas outlet pipe.

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