CN112283709A - Premixer, gas water heater and wind pressure protection method thereof - Google Patents
Premixer, gas water heater and wind pressure protection method thereof Download PDFInfo
- Publication number
- CN112283709A CN112283709A CN202011201224.0A CN202011201224A CN112283709A CN 112283709 A CN112283709 A CN 112283709A CN 202011201224 A CN202011201224 A CN 202011201224A CN 112283709 A CN112283709 A CN 112283709A
- Authority
- CN
- China
- Prior art keywords
- gas
- pressure
- wind pressure
- air
- wind
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/20—Arrangement or mounting of control or safety devices
- F24H9/2007—Arrangement or mounting of control or safety devices for water heaters
- F24H9/2035—Arrangement or mounting of control or safety devices for water heaters using fluid fuel
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/02—Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone
- F23D14/04—Premix gas burners, i.e. in which gaseous fuel is mixed with combustion air upstream of the combustion zone induction type, e.g. Bunsen burner
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/46—Details
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23D—BURNERS
- F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
- F23D14/46—Details
- F23D14/62—Mixing devices; Mixing tubes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H15/00—Control of fluid heaters
- F24H15/10—Control of fluid heaters characterised by the purpose of the control
- F24H15/104—Inspection; Diagnosis; Trial operation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H15/00—Control of fluid heaters
- F24H15/20—Control of fluid heaters characterised by control inputs
- F24H15/242—Pressure
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H15/00—Control of fluid heaters
- F24H15/30—Control of fluid heaters characterised by control outputs; characterised by the components to be controlled
- F24H15/305—Control of valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H15/00—Control of fluid heaters
- F24H15/30—Control of fluid heaters characterised by control outputs; characterised by the components to be controlled
- F24H15/395—Information to users, e.g. alarms
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Regulation And Control Of Combustion (AREA)
Abstract
The invention provides a premixer, a gas water heater and a wind pressure protection method thereof, wherein the premixer comprises a gas cavity, an air cavity and a premixing cavity, the gas cavity conveys gas through one or more gas channels, the air cavity conveys air through a Venturi channel corresponding to the gas channel, and the gas channel is positioned in the Venturi channel so that the air in the Venturi channel can inject the gas in the gas channel; the at least one venturi channel is provided with a turning plate capable of covering the outlet of the venturi channel, the turning plate can separate the venturi channel from the premixing cavity and can be turned by wind force to enable gas and air to enter the premixing cavity to be mixed. The air flow passage and the fuel gas flow passage of the premixer are separated and then converged, and the structures of the air flow passage and the dune passage increase the air pressure, so that the air has stronger capacity of ejecting fuel gas; in addition, a turning plate driven by wind power is arranged at the outlet of the Venturi passage, so that the Venturi passage can be conveniently used for acquiring a load ratio in a large range to meet the water demand.
Description
Technical Field
The invention relates to a gas mixing device, in particular to a premixer. In addition, the invention also relates to a gas water heater comprising the premixer and a wind pressure protection method of the gas water heater.
Background
In the key period of transformation of Chinese economy, the government is actively encouraging the application of natural gas in order to further reduce the environmental problems caused by the consumption of primary energy (especially coal and petroleum) in production and life of people. The burner is a general name of a device for ejecting and mixing (or ejecting and mixing) fuel and air in a certain mode for combustion, and the burner is divided into an industrial burner, a civil burner and a special burner according to types and application fields. The existing burners of household gas water heaters and heating water heaters adopt a partial premixed combustion mode design and a full premixed combustion mode design. In the partial premixing combustion mode, the gas is only mixed with partial air before combustion, secondary air is needed for supplement during combustion, and the combustion is incomplete; secondly, the air coefficient is large (generally close to or even exceed 2), the combustion flame temperature is low, and due to incomplete combustion, more harmful gases such as CO, NOx and the like are generated, thus not meeting the requirement of environmental protection. The full premix combustion mode has the advantages of small air coefficient, high flame temperature, full combustion, low contents of CO and NOx in combustion products and the like, so the full premix combustion mode is advocated.
However, the premixer (venturi) of the existing fully premixed gas water heater (wall-hanging stove) has the following defects: (1) the air and the fuel gas can only be simply premixed, and the air cannot be injected by the fuel gas or the fuel gas is injected by the air, so that the air and the fuel gas are automatically matched to obtain a proper air-fuel ratio; (2) the air-fuel ratio is adjusted by adopting the proportional valve, so that the cost is high, a larger adjusting ratio cannot be obtained, and the hot water using requirement of a user in a larger range is met; (3) reading the wind pressure on an air inlet pipe (namely a silencing pipe), transmitting a signal into a wind pressure switch, and disconnecting a circuit to perform wind pressure protection when the closing value of a wind pressure sensor is reached; when the starting value of the wind pressure sensor is recovered, the wind pressure sensor is restarted, the wind pressure read on the air inlet pipe is far away from the fan, the wind pressure value is easily influenced by the tightness of the air inlet pipe (generally in a clamping connection) and is unstable, and moreover, the wind pressure switch can only set one starting value and one closing value and cannot perform wind pressure protection on a full-load section; (4) the gas pressure can not be obtained, which is not beneficial to detecting the gas front pressure (namely the gas secondary pressure) of the nozzle of the premixer; (5) the existing premixer (Venturi) cannot obtain a good small-load combustion working condition, so that the small load is easy to cause poor smoke emission and tempering.
Disclosure of Invention
The invention provides a premixer, which can not only enhance the gas injection capability of air, but also obtain a large-range load ratio to meet different water requirements of users.
The problem to be solved by the second aspect of the invention is to provide a gas water heater, wherein the premixer of the gas water heater not only can enhance the capacity of air for injecting gas, but also can obtain a large-range load ratio so as to meet different water requirements of users.
The third aspect of the present invention is to provide a wind pressure protection method for a gas water heater, which can determine the type of fault and alarm by comparing the measured values of the secondary pressure and wind pressure of the gas with the respective upper limit value and lower limit value.
The problem to be solved by the fourth aspect of the invention is to provide a minimum load protection method for a gas water heater, which can improve the wind resistance of the gas water heater in a low-load combustion state.
In order to achieve the above object, the present invention provides a premixer, which includes a gas chamber, an air chamber and a premixing chamber, wherein the gas chamber delivers gas through one or more gas passages, the air chamber delivers air through a venturi passage corresponding to the gas passage, and the gas passage is located in the venturi passage, so that the air in the venturi passage can inject the gas in the gas passage and enter the premixing chamber for premixing; at least one be equipped with on the venturi channel can cover the board that turns over of venturi channel export, the board that turns over can separate the venturi channel with mix the chamber in advance to can receive the wind-force upset so that gas and air get into mix in the chamber in advance.
Preferably, the turning plate is provided with a boss capable of blocking the outlet of the venturi channel.
Further preferably, the boss is a cylinder or a beveled cylinder.
Preferably, a nozzle with the injection direction pointing to the premixing cavity is arranged in the gas channel.
Preferably, the bottom of the air chamber is formed as a deflector portion capable of guiding air.
Preferably, be equipped with the gas on the gas chamber and get pressure mouth, it gets pressure mouth to be equipped with the wind pressure on the venturi channel.
Further preferably, the flaps are partially provided in the plurality of venturi passages, and the wind pressure suction nozzle extends into the venturi passages without the flaps.
Still further, the size of the venturi channel without the flap is smaller than the size of the venturi channel with the flap.
In a second aspect, the invention provides a gas water heater comprising the premixer described above.
Furthermore, be equipped with the gas on the gas chamber and get pressure mouth, be equipped with the wind pressure on the venturi channel and get pressure mouth.
Furthermore, a pressure sensor is connected to the gas pressure taking nozzle, and a wind pressure sensor is connected to the wind pressure taking nozzle.
The third aspect of the present invention provides a wind pressure protection method for a gas water heater, wherein the gas water heater is provided with the premixer, and the wind pressure protection method comprises:
(1) acquiring secondary gas pressure SP and wind pressure FP;
(2) determining whether to alarm and the adopted alarm signal according to the working condition,
a. the following method is adopted to determine an alarm signal and alarm:
when the wind pressure FP is lower than the lower limit value gmin(n) or above its upper limit value gmax(n), reporting a wind pressure fault; or
When the secondary pressure SP of the fuel gas is lower than the lower limit value fmin(n) or above its upper limit value fmax(n), reporting a secondary voltage fault;
b. when the wind pressure FP is at the lower limit value gmin(n) and an upper limit value gmax(n) and the secondary pressure of the gas SP is at its lower limit fmin(n) and an upper limit value fmaxAnd (n), no alarm is given.
Further, the following method is adopted to determine an alarm signal and alarm: when the wind pressure FP is lower than the lower limit value gmin(n) or above its upper limit value gmax(n) and at the same time the secondary pressure SP of the gas is lower than its lower limit fmin(n) or above its upper limit value fmaxAnd (n), reporting the wind pressure protection fault.
The invention in a fourth aspect provides a minimum load protection method for a gas water heater, the gas water heater being provided with the premixer, the minimum load protection method comprising:
when the external wind speed is increased, the fan rotating speed n of the gas water heater is increased, so that the gas secondary pressure SP and the wind pressure FP reach the preset gas secondary pressure SP0Wind pressure FP0，
Wherein, SP0The secondary pressure of the gas when the external wind speed is 0 and the gas water heater is in normal combustion, FP0The air pressure is the air pressure when the external air speed is 0 and the gas water heater is in normal combustion.
Further, wherein the gas secondary pressure SP and the wind pressure FP cannot be made to reach the preset gas secondary pressure SP even if the fan rotation speed n is raised if the external wind speed is increased to the predetermined value0And said wind pressure FP0At the level of the secondary gas pressure SP reduced to the minimum secondary gas pressure SPminOr the wind pressure FP is reduced to the minimum wind pressure FPminIn the meantime, the fan speed n is no longer raised until the windThe pressure FP is reduced to be lower than the wind pressure protection value g corresponding to the rotating speed n of the fanminAnd (n), stopping the whole machine and reporting the wind pressure fault.
Through the technical scheme, the invention has the following beneficial effects:
1. the air flow passage and the gas flow passage of the premixer are separated and then converged, so that air and gas can be premixed for the first time in the premixer, and the structures of the air flow passage and the dune passage increase the air pressure, so that the air has stronger capacity of ejecting the gas; in addition, a turning plate driven by wind power is arranged at the outlet of the Venturi passage, so that the turning plate can be conveniently used for obtaining a load ratio in a large range to meet the water demand;
2. in the preferred technical scheme of the invention, the turning plate is provided with the lug boss capable of plugging the outlet of the Venturi channel, so that the closing effect of the Venturi channel is ensured, the combustion working condition of small load is ensured, and the exhaust smoke deterioration and even tempering caused by high fuel gas and low oxygen content are avoided;
3. in the preferred technical scheme of the invention, a gas pressure taking nozzle is arranged on a gas cavity of the premixer, the heat load can be calculated by reading the gas front pressure, and meanwhile, the gas pressure taking nozzle can be used for detecting the gas pressure intensity during debugging and after-sales maintenance so as to analyze whether the gas pressure intensity is abnormal or not; a normally open Venturi channel is provided with a wind pressure taking nozzle, so that the air pressure can be obtained at a full load section, and the wind pressure protection can be carried out when the wind pressure is abnormal;
4. the invention obtains respective upper limit value and lower limit value of the secondary gas pressure and the wind pressure by analyzing the relationship among the heat load, the heat output, the secondary gas pressure, the wind pressure and the rotating speed of the fan of the gas water heater, then judges the fault type by comparing the measured values of the secondary gas pressure and the wind pressure with the respective upper limit value and lower limit value, and protects or alarms the whole machine;
5. the invention also provides a protection mechanism in a small load state, so that the gas water heater has certain wind resistance.
Drawings
FIG. 1 is a schematic diagram of the construction of a premixer according to an embodiment of the present invention;
FIG. 2 is a top view of FIG. 1;
FIG. 3 is a bottom view of FIG. 1;
FIG. 4 is a transverse cross-sectional view of FIG. 2;
FIG. 5 is a longitudinal cross-sectional view of FIG. 2;
FIG. 6 is a schematic view of FIG. 5 with the nozzle and flap omitted;
FIG. 7 is a schematic structural view of a flap according to an embodiment of the present invention;
FIG. 8 is a left side view of FIG. 7;
FIG. 9 is a rear view of FIG. 7;
FIG. 10 is a top view of FIG. 7;
FIG. 11 is a schematic structural view of a flap according to another embodiment of the present invention;
FIG. 12 is a left side view of FIG. 11;
FIG. 13 is a rear view of FIG. 11;
FIG. 14 is a top view of FIG. 11;
FIG. 15 is a schematic view of the gas water heater of the present invention;
FIG. 16 is a relationship curve of heat load and fan speed obtained by fitting a gas water heater of a certain type of the present invention;
FIG. 17 is a graph showing the relationship between the heat output and the fan speed obtained by fitting a gas water heater of one type of the present invention;
FIG. 18 is a graph of the relationship between the secondary pressure of the fuel gas and the rotational speed of the fan obtained by fitting the fuel gas water heater of one model of the present invention;
FIG. 19 is a relationship curve of wind pressure and fan speed obtained by fitting a gas water heater of a certain model of the present invention.
Description of the reference numerals
The gas pressure measuring device comprises a gas cavity 1, a gas pressure taking nozzle 11, a gas air cavity 2, a premixing cavity 3, a gas channel 4, a nozzle 41, a turning plate 5, a boss 51, a rotating shaft 52, a premixing seat 6, a mounting hole 61, an air inlet seat 71, a wind pressure sensor 72, a wind pressure taking pipe 73, a bottom shell 74, a heat exchanger 75, a water collecting disc 76, a water seal 77, a smoke exhausting channel 78, a gas valve 79, an air inlet pipe 710, a burner 711, a controller 712, a venturi channel 8 and a wind pressure taking nozzle 81.
Detailed Description
The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.
It should be noted that, in the following description, for clarity of explanation of the technical solution of the present invention, directional terms, such as "outer", "inner", "upper", "lower", and the like, are used according to the meaning of the components of the premixer and the directional terms normally referred to when the premixer is applied to a gas water heater, for example, a portion through which gas passes is an inner portion, a portion opposite to the inner portion is an outer portion, and the top portion is an upper portion and the bottom portion is a lower portion after the gas water heater is installed. This is done solely for the purpose of facilitating the description of the invention and simplifying the description, and is not intended to indicate or imply that the device or element so referred to must be in a particular orientation, constructed and operated, and therefore should not be taken as limiting the invention.
In the description of the present invention, it should be noted that, unless otherwise explicitly stated or limited, the terms "mounted" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; either directly or indirectly through intervening media, either internally or in any combination thereof. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
As shown in fig. 1-6, the premixer of the present invention includes a gas chamber 1, an air chamber 2 and a premixing chamber 3, the gas chamber 1 delivers gas through one or more gas passages 4, the air chamber 2 delivers air through a venturi passage 8 corresponding to the gas passage 4, the gas passage 4 is located in the venturi passage 8, so that the air in the venturi passage 8 can inject the gas in the gas passage 4 and enter the premixing chamber 3 for premixing; and a turning plate 5 capable of covering the outlet of the venturi channel 8 is arranged on at least one venturi channel 8, the turning plate 5 can separate the venturi channel 8 from the premixing cavity 3 and can be turned over by wind force to enable gas and air to enter the premixing cavity 3 to be mixed.
The premixer is installed on a fan, when the fan runs, negative pressure is formed in the venturi channel 8, gas enters the gas cavity 1 from the gas inlet and then enters the gas channel 4, air enters the air cavity 2 from the air inlet and then enters the venturi channel 4, a large flow speed is generated, the gas in the gas channel 4 in the venturi channel 8 is injected, and then primary premixing is carried out in the premixing cavity 3.
In a natural state, the turning plate 5 closes the venturi channel 8 where the turning plate is located, and is gradually opened under the suction action of the fan, so that the venturi channel 8 where the turning plate is located is opened, and the turning plate 5 is completely opened at the time of maximum load. Under the condition that other factors such as gas type, gas pressure and the like are determined, the opening degree of the turning plate 5 determines the sizes of different loads, so that a user can obtain the hot water requirement in a larger range. The flap 5 is mounted on the premixer seat 6 by a rotating shaft 52.
As shown in fig. 7-14, the flap 5 is provided with a boss 51 capable of blocking the outlet of the venturi channel 8, and the boss 51 is a cylinder or a slant cylinder. When turning over board 5 and closing corresponding venturi channel 8, the export of boss 51 shutoff venturi channel 8 guarantees to turn over the effect of closing of board 5 to guarantee the burning operating mode of light load, avoid the gas to be on the high side, the too low emission flue gas variation that leads to of oxygen content, the tempering even.
In order to obtain a high gas pressure and flow rate, a nozzle 41 is provided in the gas channel 4, the injection direction of which is directed towards the premixing chamber 3. The connection between the nozzle 41 and the gas channel 4 is provided with a sealing ring to ensure that the gas does not leak.
In order to ensure the smooth and open air flow passage, the concave angle and the convex angle of the air chamber 2 need to be rounded, and the bottom of the air chamber 2 is formed as a diversion inclined plate part capable of guiding air, as shown in fig. 4, the concave angle gamma of the air chamber 2 is larger than 90 degrees and smaller than 180 degrees. The height L1 and L2 of the side walls of the air chamber 2 ensure that the air flow path is smooth and unobstructed during the process of air entering the air chamber 2 from the inlet and then exiting the air chamber 2 from the outlet.
The gas enters the gas cavity 1 from the gas inlet, the gas pressure taking nozzle 11 extends out of the side wall of the gas cavity 1, and the gas pressure, namely the gas front pressure (namely the gas secondary pressure SP) of the nozzle, can be read at the position by using a U-shaped pipe or a micro-pressure meter. By acquiring the gas front pressure, the heat load at the moment can be calculated, and meanwhile, the method can be used for detecting the gas pressure intensity during debugging and after-sales maintenance so as to analyze whether the gas is abnormal or not.
The venturi channel 8 is provided with a wind pressure taking nozzle 81. Because the Venturi channel 8 without the turning plate 5 is normally open, the pressure taking end of the wind pressure taking nozzle 81 extends into the Venturi channel, and the air pressure can be obtained at the full-load section. In addition, since the sectional area is reduced after the air enters the venturi channel 8 from the air chamber 2, the air pressure obtained here is large, and even in a small load state, the obtained air pressure can meet the judgment of the air pressure program, so that the air pressure protection is performed when the air pressure is abnormal. The diameter of the venturi channel 8 without flap 5 can be set smaller than the diameter of the venturi channel 8 with flap 5 to meet the demand of low load combustion.
In a second aspect of the present invention, as shown in fig. 15, the gas water heater includes a bottom case 74, and a fan, a heat exchanger 75, a water collecting tray 76, a water seal 77, a gas valve 79, a controller 712, a burner 711, an air inlet pipe 710, a smoke exhaust passage 78 and the above-mentioned premixer which are disposed in the bottom case 74, wherein a gas pressure taking nozzle 11 is disposed on a gas chamber 1 of the premixer, a wind pressure taking nozzle 81 is disposed on a venturi passage 8, correspondingly, a pressure sensor is connected to the gas pressure taking nozzle 11, and a wind pressure sensor 72 is connected to the wind pressure taking nozzle 81 through a wind pressure taking pipe 73. The upper sealing plate of the bottom case 74 is provided with an air inlet seat 71 connected to the air inlet pipe 710 and a smoke outlet seat connected to the smoke exhaust passage 78.
When the gas water heater works, air enters the whole machine from the air inlet seat 71, enters the premixer from the air inlet pipe 710, enters the fan for stirring, and participates in combustion in the combustor 711.
Based on the technical scheme, the invention also provides a wind pressure protection method of the gas water heater, and the wind pressure protection method comprises the following steps:
and acquiring secondary gas pressure SP and wind pressure FP, comparing the secondary gas pressure SP and the wind pressure FP with respective corresponding upper limit value and lower limit value to judge the fault type, and protecting or alarming the whole machine. For example, the following method may be used to determine the alarm signal and alarm:
when the wind pressure FP is lower than the lower limit value gmin(n) or above its upper limit value gmax(n), reporting a wind pressure fault; or when the secondary pressure SP of the fuel gas is lower than the lower limit value fmin(n) or above its upper limit value fmaxAnd (n) reporting the secondary voltage fault. The method can be divided into the following modes:
mode 1: as long as the wind pressure FP is lower than the lower limit value gmin(n) or above its upper limit value gmax(n), reporting the wind pressure fault; when the secondary pressure SP of the fuel gas is lower than the lower limit value fmin(n) or above its upper limit value fmax(n) and the wind pressure FP is at its lower limit value gmin(n) and an upper limit value gmax(n), reporting a secondary voltage fault;
mode 2: as long as the secondary pressure SP of the gas is lower than the lower limit value fmin(n) or above its upper limit value fmax(n), reporting the secondary voltage fault; when the wind pressure FP is lower than the lower limit value gmin(n) or above its upper limit value gmax(n) and the secondary gas pressure SP is at its lower limit value fmin(n) and an upper limit value fmax(n), reporting a wind pressure fault;
further, mode 3: when the wind pressure FP is lower than the lower limit value gmin(n) or above its upper limit value gmax(n) and the secondary pressure SP of the gas is lower than its lower limit value fmin(n) or above its upper limit value fmax(n), reporting a wind pressure protection fault; when the wind pressure FP is lower than the lower limit value gmin(n) or above its upper limit value gmax(n) and the secondary gas pressure SP is at its lower limit value fmin(n) and an upper limit value fmax(n), reporting a wind pressure fault; when the secondary pressure SP of the fuel gas is lower than the lower limit value fmin(n) or above its upper limit value fmax(n) and the wind pressure FP is at its lower limit value gmin(n) and an upper limit value gmaxAnd (n), reporting a secondary voltage fault.
When the wind pressure FP is at the lower limit value gmin(n) and an upper limit value gmax(n) and the secondary pressure of the gas SP is at its lower limit fmin(n) and an upper limit value fmaxAnd (n), no alarm is given.
In the above, the comparison between the gas secondary pressure SP and the wind pressure FP is performed in the controller 712, and the fault type is displayed on the display.
For example, g may bemin(n) is set as a wind pressure protection value. When the smoke pipe is blocked, the wind pressure FP corresponding to the rotating speed n of the fan operated by the whole machine is reduced to be lower than the wind pressure protection value g corresponding to the rotating speedminAnd (n), the controller 712 outputs a signal to close the gas valve 79, the whole machine stops running, and the air outlet pressure fault is reported on the display. The device can protect the whole machine from burning normally, avoid redundant waste gas generated by burning, also avoid the water seal from blowing open and avoid the smoke from being discharged into a room through the water seal.
When the wind speed of the external wind is increased, the wind pressure FP corresponding to the rotating speed n of the fan operated by the whole machine is reduced to be lower than the wind pressure protection value g corresponding to the rotating speedminAnd (n), the controller 712 outputs a signal to close the gas valve 79, the whole machine stops running, and the air outlet pressure fault is reported on the display. The device can protect the whole machine from burning normally, avoid redundant waste gas generated by burning, also avoid the water seal from blowing open and avoid the smoke from being discharged into a room through the water seal.
When the water seal is blocked, the wind pressure FP corresponding to the rotating speed n of the fan operated by the whole machine is reduced to be lower than the wind pressure protection value g corresponding to the rotating speedminAnd (n), the controller 712 outputs a signal to close the gas valve 79, the whole machine stops running, and the air outlet pressure fault is reported on the display. This can protect the complete machine burning normal, avoids burning and produces unnecessary waste gas.
The water seal, the blockage and the blowing are protected by wind pressure, and when any wind pressure reaches the wind pressure protection condition, flameout protection is carried out.
As described above, the secondary pressure SP and the wind pressure FP of the gas are obtained by the pressure sensor and the wind pressure sensor 72, respectively, and the lower limit value f of the secondary pressure SP of the gas ismin(n) and an upper limit value fmax(n) and lower limit value g of wind pressure FPmin(n) and an upper limit value gmaxThe acquisition method of (n) comprises the following steps:
1) the heat load W (or heat output Q) corresponds to the fan rotating speed n, during design, basic data of the heat load W (or heat output Q) and the fan rotating speed n of a plurality of prototype machines are collected firstly, curves of the heat load W (or heat output Q) and the fan rotating speed n are fitted, and the corresponding relation W-f of the heat load W (or heat output Q) and the fan rotating speed n is obtained through linear regression1(n) or Q ═ f2(n) of (a). And the heat load W (or heat output Q) is calculated as: respectively obtaining water inlet temperature T on a plurality of sample machines0Water flow q and water outlet temperature TtAccording to Q ═ Q (T)t-T0) Calculating heat output Q, and calculating heat load W according to the heat efficiency eta; temperature T of inlet water0Measured by an inlet water temperature sensor, the water flow q is measured by an inlet water flow sensor, and the outlet water temperature TtMeasured by a water outlet temperature sensor; for example, the heat load W and the heat output Q at each fan speed n of a certain model water heater are obtained by calculation, the results are shown in table 1, the relationship curve between the heat load and the fan speed obtained by Excel fitting regression is shown in fig. 16, the corresponding formula is W ═ 0.0079n-3.0627, the relationship curve between the heat output and the fan speed is shown in fig. 17, the corresponding formula is Q ═ 0.0085n-3.3077, and the goodness of fit (R) of the two curves is obtained2) 0.9978 and 0.9978 respectively, the fitting degree of the regression straight line to the observed value is better.
TABLE 1 Fan rotational speed, Heat output, Heat load, gas Secondary pressure and wind pressure
2) And because the rotating speed of the fan is increased, the secondary gas pressure SP and the wind pressure FP are also increased, so that the rotating speed n of the fan and the secondary gas pressure SP have a one-to-one corresponding relation, and the rotating speed n of the fan and the wind pressure FP also have a one-to-one corresponding relation. During design, basic data of fan rotating speed n and gas secondary pressure SP and wind pressure FP of a plurality of prototype machines are obtained first, and curves of the fan rotating speed n and the gas secondary pressure SP and the wind pressure FP are fittedAnd obtaining the corresponding relations SP (f) (n) and FP (g (n)) of the secondary gas pressure SP and the wind pressure FP and the fan rotating speed n by linear regression. For example, the results of measuring the secondary pressure SP of the gas and the wind pressure FP at each fan speed n of a certain model water heater are shown in table 1, and the relationship curve of the secondary pressure of the gas and the fan speed obtained by the Excel fitting regression is shown in fig. 18, which corresponds to a formula SP of 0.0323n-64.129, and the relationship curve of the wind pressure and the fan speed is shown in fig. 19, which corresponds to a formula FP of 0.1997n-242.84, and the goodness of fit (R) of the two curves is shown in table 12) 0.9624 and 0.9731, the regression line has a better fit to the observed values.
3) Acquiring basic data of heat load W, heat output Q, fan rotating speed n, gas secondary pressure SP and wind pressure FP of a plurality of prototype machines, and then according to the inlet water temperature T when the prototype machines run0Water flow q and water outlet temperature TtThe range of the heat output Q or the heat load W is calculated, and then the corresponding relation W ═ f of the heat load W, the heat output Q, the fan rotating speed n, the basic data of the secondary gas pressure SP and the wind pressure FP and the corresponding relation W ═ f of the heat load W or the heat output Q and the fan rotating speed n1(n) or Q ═ f2(n), determining the range of the rotating speed n of the fan, determining the range of secondary gas pressure SP and wind pressure FP according to the range of the rotating speed n of the fan, and finally obtaining the lower limit value f of the secondary gas pressure SPmin(n) and an upper limit value fmax(n) and lower limit value g of wind pressure FPmin(n) and an upper limit value gmax(n)。
On the other hand, if the premixer is provided with a plurality of venturi passages 8, the minimum load state is when the flap 5 is closed. Since the fan speed n is small in the minimum load state, the secondary pressure SP and the wind pressure FP are also small. At this time, when the external wind speed is high, the flame is easily blown out, so that the minimum secondary gas pressure SP is setminAnd minimum wind pressure FPmin. Based on the above, the invention also provides a minimum load protection method of the gas water heater, which comprises the following steps:
when the gas water heater burns in a small load section, if the external wind speed is 0, the secondary pressure of the gas water heater during normal burning is SP0Wind pressure is FP0At this time in a burning stateThe state is optimal.
When the external wind speed increases, the secondary pressure SP and the wind pressure FP of the gas during the combustion of the small load section are reduced. Once the secondary gas pressure SP and the wind pressure FP decrease, the controller 712 analyzes and processes to increase the fan speed n of the gas water heater, so that the secondary gas pressure SP and the wind pressure FP are restored to the preset secondary gas pressure SP0Wind pressure FP0To maintain normal combustion, so that the gas water heater (wall-mounted boiler) has certain wind resistance;
if the external wind speed is increased to the value that the gas secondary pressure SP and the wind pressure FP can not reach the preset gas secondary pressure SP even if the rotating speed n of the fan is increased0Wind pressure FP0For example, when the external wind speed increases suddenly or the external wind speed increases excessively, the fan speed n cannot be increased or the fan speed n is out of the range, and the secondary gas pressure SP is reduced to the minimum secondary gas pressure SPminOr the wind pressure FP is reduced to the minimum wind pressure FPminIn the process, the rotating speed n of the fan is not increased until the wind pressure FP is reduced to a wind pressure protection value g corresponding to the rotating speed n of the fanminAnd (n), closing the gas valve 79, stopping the whole machine, and reporting the wind pressure fault.
Based on this, the minimum gas secondary pressure SP can be setminWind pressure FPminAnd (4) adjusting the wind resistance of the whole machine.
The following is a preferred embodiment of the premixer of the present invention.
As shown in fig. 1-6, the premixer of the invention includes a gas chamber 1, an air chamber 2 and a premixing chamber 3, the gas chamber 1 delivers gas through two gas passages 4, the air chamber 2 delivers air through two venturi passages 8 corresponding to the gas passages 4, one gas passage 4 is arranged in one venturi passage 8, each gas passage 4 is provided with a nozzle 41, the two nozzles 41 have different diameters, the size of the venturi passage 8 corresponding to the large-diameter nozzle 41 is large, a flap 5 capable of covering the outlet of the venturi passage 8 is arranged at the outlet, the flap 5 can separate the venturi passage 8 from the premixing chamber 3 and can be turned over by wind force to mix the gas and the air into the premixing chamber 3, and the flap 5 is provided with a boss 51 capable of blocking the outlet of the venturi passage 8. The gas cavity 1 is provided with a gas pressure taking nozzle 11, and the venturi channel 8 corresponding to the nozzle 41 with the small diameter is provided with a wind pressure taking nozzle 81.
When the premixer is used, the premixer is arranged at an inlet of a fan of a gas water heater through the mounting hole 61 on the premixer seat 6, the pressure taking end of the wind pressure taking nozzle 81 faces upwards, and the pressure taking end of the gas pressure taking nozzle 11 faces downwards. In a natural state, the flap 5 sags under the action of gravity to close the venturi channel 8 corresponding to the large nozzle 41. When the load is small, the air volume of the fan is small, the turning plate 5 closes the venturi channel 8 corresponding to the nozzle 41 with the larger diameter, and all the fuel gas flows out of the venturi channel 8 corresponding to the nozzle 41 with the smaller diameter; along with the increase of the air volume, the turning plate 5 is gradually turned upwards under the suction force of the air, and the venturi channels 8 corresponding to the larger nozzles 41 are opened, so that the fuel gas flows out of the two venturi channels 8 simultaneously; at maximum load, the flap 5 is fully open. Under the condition that other factors such as the type of fuel gas, the pressure of the fuel gas, the diameter of the nozzle 41 and the like are determined, the opening degree of the turning plate 5 determines the sizes of different loads. The load regulation ratio of the whole machine is regulated by the diameter d of a large nozzle1And small nozzle diameter d2Determine when (d)1 2+d2 2)/d2 2If it is more than 5, the adjustment ratio is more than 10: 1.
The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.
It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.
In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.
Claims (15)
1. A premixer is characterized by comprising a gas cavity (1), an air cavity (2) and a premixing cavity (3), wherein the gas cavity (1) conveys gas through one or more gas passages (4), the air cavity (2) conveys air through a Venturi passage (8) corresponding to the gas passage (4), and the gas passage (4) is positioned in the Venturi passage (8) so that the air in the Venturi passage (8) can inject the gas in the gas passage (4) and enter the premixing cavity (3) for premixing;
at least one venturi channel (8) is provided with a turning plate (5) capable of covering the outlet of the venturi channel (8), the turning plate (5) can separate the venturi channel (8) and the premixing cavity (3) and can be turned over by wind force to enable gas and air to enter the premixing cavity (3) for mixing.
2. The premixer according to claim 1, wherein the flap (5) is provided with a boss (51) capable of blocking the outlet of the venturi channel (8).
3. The premixer according to claim 2, wherein the boss (51) is a cylinder or a beveled cylinder.
4. The premixer according to claim 1, wherein a nozzle (41) with an injection direction directed to the premixing chamber (3) is provided in the gas channel (4).
5. The premixer according to claim 1, wherein the bottom of the air chamber (2) is formed as a deflector ramp portion capable of guiding air.
6. The premixer according to any one of claims 1 to 5, wherein a gas pressure taking nozzle (11) is provided on the gas chamber (1), and a wind pressure taking nozzle (81) is provided on the venturi channel (8).
7. The premixer according to claim 6, wherein the flap (5) is partially provided in the plurality of venturi passages (8), and the wind pressure tap (81) is extended into the venturi passage (8) without the flap (5).
8. The premixer according to claim 7, wherein the size of the venturi channel (8) without the flap (5) is smaller than the size of the venturi channel (8) with the flap (5).
9. A gas water heater comprising a premixer according to any one of claims 1 to 5.
10. The gas water heater of claim 9, characterized in that the gas chamber (1) is provided with a gas pressure tap (11), and the venturi channel (8) is provided with a wind pressure tap (81).
11. The gas water heater of claim 10, wherein a pressure sensor is connected to the gas pressure taking nozzle (11), and a wind pressure sensor (72) is connected to the wind pressure taking nozzle (81).
12. A wind pressure protection method for a gas water heater is characterized in that the gas water heater is provided with a premixer according to any one of claims 1 to 8,
the wind pressure protection method comprises the following steps:
(1) acquiring secondary gas pressure SP and wind pressure FP;
(2) determining whether to alarm and the adopted alarm signal according to the working condition,
a. the following method is adopted to determine an alarm signal and alarm:
when the wind pressure FP is lower than the lower limit value gmin(n) or above its upper limit value gmax(n), reporting a wind pressure fault; or
When the secondary pressure SP of the fuel gas is lower than the lower limit value fmin(n) or above its upper limit value fmax(n), reporting a secondary voltage fault;
b. when the wind pressure FP is at the lower limit value gmin(n) and an upper limit value gmax(n) and the secondary pressure of the gas SP is at its lower limit fmin(n) and an upper limit value fmaxAnd (n), no alarm is given.
13. The wind pressure protection method of the gas water heater according to claim 12, characterized in that the alarm signal is determined and alarmed by the following method: when the wind pressure FP is lower than the lower limit value gmin(n) or above its upper limit value gmax(n) and at the same time the secondary pressure SP of the gas is lower than its lower limit fmin(n) or above its upper limit value fmaxAnd (n), reporting the wind pressure protection fault.
14. Method for minimum load protection of a gas water heater, characterized in that a premixer according to any one of claims 1 to 8 is provided on the gas water heater,
the minimum load protection method comprises the following steps:
when the external wind speed is increased, the fan rotating speed n of the gas water heater is increased, so that the gas secondary pressure SP and the wind pressure FP reach the preset gas secondary pressure SP0Wind pressure FP0，
Wherein, SP0The secondary pressure of the gas when the external wind speed is 0 and the gas water heater is in normal combustion, FP0The air pressure is the air pressure when the external air speed is 0 and the gas water heater is in normal combustion.
15. The minimum load protection method of a gas water heater according to claim 14, wherein if the outside wind speed increases to such a degree that the gas secondary pressure SP and the wind pressure FP cannot be brought to the preset gas secondary pressure SP even if the fan speed n is raised0And said wind pressure FP0At the level of the secondary gas pressure SP reduced to the minimum secondary gas pressure SPminOr the wind pressure FP is reduced to the minimum wind pressure FPminAnd the fan rotating speed n is not promoted any more until the wind pressure FP is reduced to be lower than the wind pressure protection corresponding to the fan rotating speed nValue gminAnd (n), stopping the whole machine and reporting the wind pressure fault.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311443654.7A CN117490251A (en) | 2020-11-02 | 2020-11-02 | Gas water heater and its wind pressure protection method and minimum load protection method |
| CN202011201224.0A CN112283709B (en) | 2020-11-02 | 2020-11-02 | Premixer, gas water heater and wind pressure protection method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011201224.0A CN112283709B (en) | 2020-11-02 | 2020-11-02 | Premixer, gas water heater and wind pressure protection method thereof |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311443654.7A Division CN117490251A (en) | 2020-11-02 | 2020-11-02 | Gas water heater and its wind pressure protection method and minimum load protection method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112283709A true CN112283709A (en) | 2021-01-29 |
| CN112283709B CN112283709B (en) | 2025-05-13 |
Family
ID=74354315
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011201224.0A Active CN112283709B (en) | 2020-11-02 | 2020-11-02 | Premixer, gas water heater and wind pressure protection method thereof |
| CN202311443654.7A Pending CN117490251A (en) | 2020-11-02 | 2020-11-02 | Gas water heater and its wind pressure protection method and minimum load protection method |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311443654.7A Pending CN117490251A (en) | 2020-11-02 | 2020-11-02 | Gas water heater and its wind pressure protection method and minimum load protection method |
Country Status (1)
| Country | Link |
|---|---|
| CN (2) | CN112283709B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114165785A (en) * | 2021-12-29 | 2022-03-11 | 芜湖美的厨卫电器制造有限公司 | Combustor and water heater |
| CN115235121A (en) * | 2021-04-19 | 2022-10-25 | 芜湖美的厨卫电器制造有限公司 | Gas water heater, control method and device thereof and computer readable storage medium |
| WO2023011516A1 (en) * | 2021-08-04 | 2023-02-09 | 芜湖美的厨卫电器制造有限公司 | Premixing device for water heater and water heater having same |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080124668A1 (en) * | 2006-10-18 | 2008-05-29 | Honeywell International Inc. | Systems and methods for controlling gas pressure to gas-fired appliances |
| KR20130098816A (en) * | 2012-02-28 | 2013-09-05 | 주식회사 경동나비엔 | Dual venturi for water heater |
| CN104246369A (en) * | 2012-04-23 | 2014-12-24 | 庆东纳碧安株式会社 | Combustion device for improving turndown ratio |
| CN209588395U (en) * | 2019-01-31 | 2019-11-05 | 山东卓力电器有限公司 | A kind of burnt gas wall hanging furnace condensate water-proof device and its wall hanging furnace apparatus |
| CN210485713U (en) * | 2019-06-25 | 2020-05-08 | 芜湖美的厨卫电器制造有限公司 | Venturi device and gas equipment |
| CN214147881U (en) * | 2020-11-02 | 2021-09-07 | 芜湖美的厨卫电器制造有限公司 | Premixer and gas water heater |
-
2020
- 2020-11-02 CN CN202011201224.0A patent/CN112283709B/en active Active
- 2020-11-02 CN CN202311443654.7A patent/CN117490251A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080124668A1 (en) * | 2006-10-18 | 2008-05-29 | Honeywell International Inc. | Systems and methods for controlling gas pressure to gas-fired appliances |
| KR20130098816A (en) * | 2012-02-28 | 2013-09-05 | 주식회사 경동나비엔 | Dual venturi for water heater |
| CN104246369A (en) * | 2012-04-23 | 2014-12-24 | 庆东纳碧安株式会社 | Combustion device for improving turndown ratio |
| CN209588395U (en) * | 2019-01-31 | 2019-11-05 | 山东卓力电器有限公司 | A kind of burnt gas wall hanging furnace condensate water-proof device and its wall hanging furnace apparatus |
| CN210485713U (en) * | 2019-06-25 | 2020-05-08 | 芜湖美的厨卫电器制造有限公司 | Venturi device and gas equipment |
| CN214147881U (en) * | 2020-11-02 | 2021-09-07 | 芜湖美的厨卫电器制造有限公司 | Premixer and gas water heater |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115235121A (en) * | 2021-04-19 | 2022-10-25 | 芜湖美的厨卫电器制造有限公司 | Gas water heater, control method and device thereof and computer readable storage medium |
| WO2023011516A1 (en) * | 2021-08-04 | 2023-02-09 | 芜湖美的厨卫电器制造有限公司 | Premixing device for water heater and water heater having same |
| CN114165785A (en) * | 2021-12-29 | 2022-03-11 | 芜湖美的厨卫电器制造有限公司 | Combustor and water heater |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112283709B (en) | 2025-05-13 |
| CN117490251A (en) | 2024-02-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112283709A (en) | Premixer, gas water heater and wind pressure protection method thereof | |
| EP2909536B1 (en) | Apparatus for controlling and adjusting the combustion in a fuel gas burner | |
| CN107525265A (en) | Blowing type gas water heater adopting flame temperature detection and wind speed compensation | |
| CN110953709B (en) | Gas water heating equipment | |
| CN111174412A (en) | Gas water heating equipment | |
| WO2023247690A1 (en) | Retrofit kit assembly | |
| CN209399368U (en) | The low nitrogen gas burner of L-type | |
| CN214147881U (en) | Premixer and gas water heater | |
| CN110671717B (en) | Combustion accurate control system for steam power generation boiler | |
| CN211424419U (en) | Tail gas combustion equipment | |
| KR100406472B1 (en) | Air proportionality type boiler using air pressure sensor | |
| CA3090502C (en) | Dual input water heater | |
| JP6508515B2 (en) | boiler | |
| CN113932207B (en) | Double-furnace boiler | |
| CN217763412U (en) | Precision detection execution control system of combustion heat exchanger | |
| CN111396918A (en) | Environment-friendly intelligent combustor control system | |
| CN218442271U (en) | Gas fuel combustion machine | |
| CN223360887U (en) | A gas furnace with a wind pressure sensor | |
| TWI804316B (en) | Smart boiler structure that can monitor temperature and combustion ratio | |
| CN216384619U (en) | Wall-mounted furnace based on full premixed combustion | |
| CN208779726U (en) | A kind of gas heater for monitoring blower and entering air quantity | |
| CN213810609U (en) | High-efficiency combustor | |
| JPH0749221Y2 (en) | Exhaust gas reburn burner | |
| JP5017249B2 (en) | Incomplete combustion detector | |
| CN110274396B (en) | Control method of full-premix gas water heater and gas water heater |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |