Control device for restraining unstable combustion through transverse jet flow

Abstract

The utility model discloses a control device for restraining unstable combustion through transverse jet flow, which comprises a suction part, a flow and temperature adjusting part and a gas jet flow part, the suction part comprises a gas cooler and an induced draft fan, and the flow and temperature adjusting part comprises a drying expansion box, a rotor flow meter and a gas heater. The gas jet part comprises a jet pipe bundle, an inlet pipeline of gas to be jetted is connected with the gas inlet end of a gas cooler, the gas outlet end of the gas cooler is connected with the inlet end of an induced draft fan through a gas pipeline, and the outlet end of the induced draft fan is connected with the inlet end of a drying expansion box through a gas pipeline. The outlet end of the drying expansion box is connected with the inlet end of the rotor flow meter through a pipeline, the outlet end of the rotor flow meter is connected with the inlet end of the gas heater through a pipeline, the outlet end of the gas heater is connected with the inlet end of the jet pipe bundle through a pipeline, and the outlet end of the jet pipe bundle is communicated with the interior of the combustion chamber through a pipeline.

Description

Technical Field

[0001] The utility model belongs to the technical field of suppressing combustion instability, and in particular relates to a control device for suppressing combustion instability by a lateral jet. Background Art

[0002] In order to achieve low pollutant emissions during the combustion process, lean-burn technology has been proposed. However, when the combustion process is in a lean-burn state, the acoustic waves and heat release in the combustion chamber are easily coupled, causing high-amplitude pressure oscillations, that is, combustion instability. This will not only cause damage to the burner structure, but also cause flame extinction and flashback, posing a serious threat to the safety of equipment operation.

[0003] There are many factors that cause combustion instability, but they are all closely related to the flow field organization and mixing process of fuel and air in the combustion chamber. Since the cross-flow jet will produce a rich vortex structure, it can not only change the flame-air mixing process, but also affect the recirculation zone around the flame, further affecting the fuel combustion process. Therefore, the use of gas jets into the combustion chamber is considered to be a very effective combustion instability control strategy. Jet parameters including jet position, jet flow, jet medium and jet temperature can all be adjusted to achieve combustion adjustment, which is used to suppress the occurrence of combustion instability. In order to suppress combustion instability and reduce pressure pulsation in the combustion chamber, researchers usually adopt the method of changing combustion conditions and adding acoustic dampers in the pipeline.

[0004] Existing technologies can achieve the effect of controlling unstable combustion, but the jet media used are mostly high-purity gases. At the same time, the designed jet systems are relatively simple and do not include temperature control, making it impossible to achieve variable temperature regulation of the jet media. Summary of the invention

[0005] In order to solve the above technical problems existing in the prior art, the utility model provides a control device for suppressing unstable combustion by lateral jet. The utility model can realize gas jets of complex components, and the application scenarios are more flexible. It can realize the adjustment of multiple parameters such as flow rate, temperature, height, etc. It can also realize large flow circulation and large flow jet. The jet airflow velocity can be adjusted by changing the inner diameter of the jet tube, and can be flexibly used in actual processes.

[0006] The technical solution adopted by the utility model is:

[0007] A control device for suppressing unstable combustion by transverse jets, characterized in that it comprises a suction part, a flow and temperature regulating part and a gas jet part, wherein the suction part comprises a gas cooler and an induced draft fan, the flow and temperature regulating part comprises a drying expansion box, a rotor flowmeter and a gas heater, and the gas jet part comprises a jet tube bundle, wherein:

[0008] The inlet pipeline of the gas to be jetted is connected to the gas inlet end of the gas cooler, the gas outlet end of the gas cooler is connected to the inlet end of the induced draft fan through a gas pipeline, the outlet end of the induced draft fan is connected to the inlet end of the drying expansion box through a gas pipeline, the outlet end of the drying expansion box is connected to the inlet end of the rotor flowmeter through a pipeline, the outlet end of the rotor flowmeter is connected to the inlet end of the gas heater through a pipeline, the outlet end of the gas heater is connected to the inlet end of the jet tube bundle through a pipeline, and the outlet end of the jet tube bundle is connected to the inside of the combustion chamber through a pipeline.

[0009] Furthermore, a desiccant for removing moisture is provided inside the drying and expansion box.

[0010] Furthermore, an atmosphere communication pipeline connected to the atmosphere is provided on the top of the drying expansion box, and a regulating valve is provided on the atmosphere communication pipeline.

[0011] Furthermore, the jet tube bundle is composed of a plurality of jet tubes arranged in parallel.

[0012] Furthermore, the jet tube bundle axis is 0 to 10 mm above the combustion chamber inlet plane, where the combustion chamber inlet plane is the plane where the flame root is located.

[0013] Furthermore, the cross section of the jet tube is circular.

[0014] Furthermore, the number and inner diameter of the jet tubes can be adjusted according to actual combustion conditions.

[0015] Furthermore, the temperature of the gas to be injected coming out of the gas cooler is lower than the maximum allowable operating temperature of the motor of the induced draft fan.

[0016] Furthermore, a gas inlet is arranged at the top of the drying expansion box, and a gas outlet is arranged near the bottom.

[0017] Furthermore, the gas flow correction coefficient of the rotor flowmeter can be calculated according to the following formula (1):

[0018]

[0019] Among them, the parameters with subscript n are the calibration gas parameters corresponding to the rotor flowmeter under standard working conditions, and Q, ρ, Z, p and T represent the gas flow, density, compressibility, pressure and temperature respectively.

[0020] Compared with the prior art, the beneficial effects of the utility model are embodied in:

[0021] 1. The jet medium of the utility model can select different types of complex gases (such as high-temperature flue gas), and can realize volume flow measurement and control, breaking through the limitation of single gas jet;

[0022] 2. The utility model realizes variable temperature control of jet gas, improving the disadvantage that low-temperature gas jet will reduce the average temperature of the combustion chamber;

[0023] 3. The existence of the regulating valve of the utility model can ensure that the induced draft fan is within a stable working flow range, and the variable diameter of the jet tube bundle can adapt to the requirements of jet momentum of different sizes;

[0024] 4. The utility model removes moisture that may be contained in the gas through a desiccant, eliminates interference with flow control, roughly adjusts the flow through a regulating valve, controls the flow size at the outlet of the drying expansion box, and then adjusts the flow through a calibrated rotor flowmeter. Finally, a gas heater is used to achieve jet gas temperature control. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0026] Figure 2a It is a schematic diagram of the structure of the jet tube of the utility model.

[0027] Figure 2b yes Figure 2a Top view of the .

[0028] Figure 3 The utility model is applied to the schematic diagram of the gas self-excited combustion system.

[0029] Figure 4 The utility model is applied to the horizontal schematic diagram of the pressure pulsation control of the combustion chamber in the gas self-excited combustion system. DETAILED DESCRIPTION

[0030] The specific implementation of the embodiment of the utility model is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the utility model, and is not used to limit the embodiment of the utility model.

[0031] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0032] The present invention will be described in detail below with reference to the accompanying drawings and in combination with exemplary embodiments.

[0033] refer to Figure 12, a control device for suppressing unstable combustion by transverse jets of the utility model comprises a suction part, a flow and temperature regulating part and a gas jet part, wherein the suction part comprises a gas cooler 1 and an induced draft fan 2, the flow and temperature regulating part comprises a drying expansion box 3, a rotor 6 and a gas heater 7, and the gas jet part comprises a jet tube bundle 8, wherein:

[0034] The inlet pipeline of the gas to be jetted is connected to the gas inlet end of the gas cooler 1, the gas outlet end of the gas cooler 1 is connected to the inlet end of the induced draft fan 2 through a gas pipeline, the outlet end of the induced draft fan 2 is connected to the inlet end of the drying expansion box 3 through a gas pipeline, the outlet end of the drying expansion box 3 is connected to the inlet end of the rotor flowmeter 6 through a pipeline, the outlet end of the rotor flowmeter 6 is connected to the inlet end of the gas heater 7 through a pipeline, the outlet end of the gas heater 7 is connected to the inlet end of the jet tube bundle 8 through a pipeline, and the outlet end of the jet tube bundle 8 is connected to the inside of the combustion chamber through a pipeline.

[0035] In one embodiment, a desiccant 4 for removing moisture is disposed inside the drying expansion box 3 .

[0036] In one embodiment, an atmosphere communication pipeline connected to the atmosphere is disposed on the top of the drying expansion box 3 , and a regulating valve 5 is disposed on the atmosphere communication pipeline.

[0037] In one embodiment, the jet tube bundle 8 is composed of a plurality of jet tubes arranged in parallel.

[0038] In one embodiment, the jet tube bundle axis is 0 to 10 mm above the combustion chamber inlet plane, where the combustion chamber inlet plane is the plane where the flame root is located.

[0039] In one embodiment, the cross section of the jet tube is circular.

[0040] In one embodiment, the number and inner diameter of the jet tubes can be adjusted according to actual combustion conditions to ensure variable adjustment of the single-tube jet momentum under the condition that the total flow rate of the gas to be jetted is the same.

[0041] In one embodiment, the temperature of the gas to be injected coming out of the gas cooler 1 is lower than the maximum allowable operating temperature of the motor of the induced draft fan 2 .

[0042] In one embodiment, a gas inlet is arranged at the top of the drying expansion box 3, and a gas outlet is arranged near the bottom.

[0043] In one embodiment, the gas flow correction coefficient of the rotor flowmeter 6 can be calculated according to the following formula (1):

[0044]

[0045] Among them, the parameters with subscript n are the calibration gas parameters corresponding to the rotor flowmeter under standard working conditions, and Q, ρ, Z, p and T represent the gas flow, density, compressibility, pressure and temperature respectively.

[0046] In the utility model, the induced draft fan 2 provides the power for the gas flow in the system and prevents the excessively high temperature of the sucked gas from causing damage to the pipeline and the induced draft fan motor; the gas to be ejected is sucked into the system through the pipeline at the inlet of the gas cooler 1, and the gas with a higher temperature is cooled by the gas cooler 1 to ensure that the temperature of the gas to be ejected is lower than the maximum allowable operating temperature of the motor of the induced draft fan 2; after the gas to be ejected enters the drying expansion box 3, the moisture contained in it will be removed by the internal desiccant 4, eliminating the interference of the moisture in the gas on the flow measurement and control; the regulating valve 5 can adjust the gas to be ejected into the rotor flowmeter 6 through the valve opening Flow rate, excess gas to be injected can be discharged into the atmosphere through the regulating valve 5, so as to ensure that the induced draft fan always works within a relatively stable flow range; the rotor flowmeter 6 calibrated by flow rate can measure the volume flow rate of different types of gases, and transport them to the gas heater 7 for temperature adjustment to achieve variable temperature control of the gas to be injected; the gas to be injected flowing out of the outlet of the gas heater 7 will enter the jet tube bundle 8, and will be injected into the burner from the outlet of the jet tube bundle 8. The inner diameter and number of the jet tube bundle 8 can be adjusted according to the actual combustion conditions to ensure that the single-tube jet momentum can be adjusted variable under the condition of the same total flow rate of the gas to be injected.

[0047] Referring to Figure 2, the utility model is applied to the coal gas self-excited combustion system. In actual operation, the outlet flue gas of the burner is sucked into the utility model, that is, sucked into the inlet end of the gas cooler 1, and the high-temperature flue gas is first cooled by the gas cooler to below the operating temperature of the induced draft fan motor, and then enters the drying expansion tank to be dehumidified by the desiccant (for example, color-changing silica gel desiccant), and the excess flue gas is discharged into the atmosphere through the regulating valve, and the rotor flowmeter controls the volume flow of the jet flue gas after the flow correction of the flue gas, and the gas heater ensures that the temperature of the jet flue gas is within a controllable range, and finally injected into the combustion chamber through the jet tube bundle to achieve pressure pulsation control, thereby suppressing the combustion instability phenomenon.

[0048] According to the above implementation process, the unstable combustion process of the gas flame is controlled, the jet flue gas temperature is controlled at 20°C, the jet tube is located 5mm above the inlet plane of the combustion chamber, and the jet tube bundle is composed of 4 circular cross-section jet tubes with an inner diameter of 1.2mm. The combustion chamber pressure pulsation control level is obtained when the total jet flue gas flow rate is 3-15L / min, where 0L / min represents the pressure pulsation level without transverse jet control. The results show that when the jet flow rate reaches 15L / min, the pressure pulsation is suppressed by 91.6%.

[0049] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0050] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0051] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0053] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0054] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A control device for suppressing combustion instability by lateral jet, characterized in that: It includes a suction part, a flow and temperature regulating part and a gas jet part, wherein the suction part includes a gas cooler and an induced draft fan, the flow and temperature regulating part includes a drying expansion box, a rotor flowmeter and a gas heater, and the gas jet part includes a jet tube bundle, wherein: The inlet pipeline of the gas to be jetted is connected to the gas inlet end of the gas cooler, the gas outlet end of the gas cooler is connected to the inlet end of the induced draft fan through a gas pipeline, the outlet end of the induced draft fan is connected to the inlet end of the drying expansion box through a gas pipeline, the outlet end of the drying expansion box is connected to the inlet end of the rotor flowmeter through a pipeline, the outlet end of the rotor flowmeter is connected to the inlet end of the gas heater through a pipeline, the outlet end of the gas heater is connected to the inlet end of the jet tube bundle through a pipeline, and the outlet end of the jet tube bundle is connected to the inside of the combustion chamber through a pipeline.

2. A control device for suppressing combustion instability by lateral jet according to claim 1, characterized in that: A desiccant for removing moisture is arranged inside the drying and expansion box.

3. A control device for suppressing combustion instability by lateral jet according to claim 1, characterized in that: An atmosphere communication pipeline connected to the atmosphere is arranged on the top of the drying expansion box, and a regulating valve is arranged on the atmosphere communication pipeline.

4. A control device for suppressing combustion instability by lateral jet according to claim 1, characterized in that: The jet tube bundle is composed of a plurality of jet tubes arranged in parallel.

5. A control device for suppressing combustion instability by lateral jet according to claim 4, characterized in that: The axis of the jet tube bundle is located 0 to 105 mm above the inlet plane of the combustion chamber.

6. A control device for suppressing combustion instability by lateral jet according to claim 4, characterized in that: The cross section of the jet tube is circular.

7. A control device for suppressing combustion instability by lateral jet according to claim 5, characterized in that: The number and inner diameter of the jet tubes can be adjusted according to actual combustion conditions.

8. A control device for suppressing combustion instability by lateral jet according to claim 1, characterized in that: The temperature of the gas to be injected coming out of the gas cooler is lower than the maximum allowable operating temperature of the motor of the induced draft fan.

9. A control device for suppressing combustion instability by lateral jet according to claim 1, characterized in that: A gas inlet is arranged at the top of the drying expansion box, and a gas outlet is arranged near the bottom.

10. A control device for suppressing combustion instability by lateral jet according to claim 1, characterized in that: The gas flow correction coefficient of the rotor flowmeter can be calculated according to the following formula (1): Among them, the parameters with subscript n are the calibration gas parameters corresponding to the rotor flowmeter under standard working conditions, and Q, ρ, Z, p and T represent the gas flow, density, compressibility, pressure and temperature respectively.

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