Non-premixed flame testing device for porous medium burner

Abstract

The utility model discloses a non-premixed flame testing device for a porous medium combustor. The non-premixed flame testing device comprises a fuel supply system, an oxidant supply system, a detection system, a combustion chamber and the porous medium combustor, the gas inlet end of the combustion chamber is in fluid communication with the fuel supply system and the oxidizing agent supply system, and fuel and oxidizing agents enter the combustion chamber through independent channels and are subjected to mixed combustion in the porous medium combustor. The porous medium combustor is composed of multiple layers of porous ceramic plates, and the porosity of the porous medium combustor is distributed in a gradient mode in the flowing direction. The flow of the fuel and the oxidant is independently controlled through a proportioning valve, and a flame stabilizer and a temperature sensor are arranged in the combustion chamber. The detection system comprises a high-speed camera, a spectrum analyzer and a gas sampling device and is used for monitoring the flame form, the temperature field and pollutant emission in real time. The device can simulate non-premixed combustion conditions, realizes accurate testing of flame stability, combustion efficiency and emission characteristics, and is suitable for optimization research of porous medium combustors.

Description

TECHNICAL FIELD

[0001] The utility model relates to combustion technical field, concretely relates to a porous medium combustor non premixed flame testing arrangement, and it is applicable to research porous medium material's influence to non premixed flame stability, combustion efficiency and pollutant generation. BACKGROUND

[0002] Porous medium combustor becomes the research hotspot of clean combustion technology because of its high thermal efficiency, low pollutant emission and wide load regulation range. However, the propagation characteristics of non premixed flame in porous medium are complex, the existing testing arrangement is difficult to accurately control the mixing ratio of fuel and oxidant, and lacks the synchronous monitoring means for flame form, temperature field and transient emission. In addition, the traditional combustion chamber structure is single, cannot simulate the gradient pore characteristics of porous medium in actual working condition, leading to the large deviation of experimental data and actual application. Therefore, a special testing arrangement capable of accurately regulating and controlling combustion conditions and realizing multi-parameter detection is urgently needed. SUMMARY

[0003] The utility model discloses a porous medium combustor non premixed flame testing arrangement, to solve the problem that the mixing ratio of fuel and oxidant is difficult to accurately control when testing non premixed flame in the prior art, the combustion condition simulation is not true, and the flame form, temperature field and pollutant emission parameter cannot be synchronously and comprehensively monitored. In order to realize the above-mentioned purpose, the technical scheme adopted by the utility model is described in detail as follows:

[0004] The porous medium combustor non premixed flame testing arrangement mainly includes a fuel supply system, an oxidant supply system, a combustion chamber (11), a porous medium combustor (9) and a detection system.

[0005] The combustion chamber (11) is a closed cavity, and the fuel inlet and the oxidant inlet are independently arranged in the air inlet end. The output end of the fuel supply system is connected to the fuel inlet through a fuel delivery pipeline; the output end of the oxidant supply system is connected to the oxidant inlet through an oxidant delivery pipeline. In this way, fuel and oxidant are kept isolated before entering the combustion chamber (11), are delivered through independent channels, and realize non premixing in the internal space of the combustion chamber (11).

[0006] The fuel supply system includes a fuel tank (6), a fuel booster pump (7) and a fuel delivery pipe (8). The fuel delivery pipe (8) is provided with a flow equalizer (3), a proportional regulating valve (4) and a fuel flowmeter (5) in sequence along the flow direction. The flow equalizer (3) adopts a honeycomb structure for uniform gas distribution. The end of the fuel delivery pipe (8), i.e. the outlet end, is firmly connected to the fuel inlet of the combustion chamber (11) through flange sealing connection.

[0007] The oxidant supply system comprises a blower (1), a gas preheater (2) and an oxidant delivery pipe (16). The oxidant delivery pipe (16) is sequentially provided with an oxidant flow meter (5) and a proportional regulating valve (4) along the flow direction. The gas preheater (2) is used for heating the oxidant (such as air). The end of the oxidant delivery pipe (16), i.e. the outlet end, is flexibly connected to the oxidant inlet of the combustion chamber (11) through a bellows to compensate for installation errors and thermal expansion.

[0008] The porous medium burner (9) is fixedly installed in the central region inside the combustion chamber (11). It comprises a cylindrical shell (17) and a plurality of layers of porous ceramic plates (18) stacked inside the shell (17). The porosity of the porous ceramic plates (18) is gradiently increased from 30% to 60% along the air flow direction (from the air inlet side to the air outlet side). Adjacent two layers of porous ceramic plates (18) are fixedly bonded by a high-temperature resistant adhesive to form a gradient porous medium structure as a whole.

[0009] A flame stabilizer (20) is fixedly arranged at the outlet end (i.e. the downstream end of the air flow) of the porous medium burner (9). The flame stabilizer (20) is a porous metal disc uniformly provided with a large number of through holes on the disc surface. The diameters of the through holes are in the range of 2-5 mm, belonging to the micro-hole structure, for stabilizing the flame and adjusting the flow field.

[0010] The gas outlet end of the combustion chamber (11) is connected to the detection system through an exhaust pipe for conveying the flue gas after combustion to the detection system for analysis.

[0011] The detection system comprises a high-speed camera (13), a spectral analyzer (14) and a gas sampling probe (12). The high-speed camera (13) is aimed at a quartz observation window arranged on the side wall of the combustion chamber (11) for capturing and recording the shape and dynamics of the flame. The detection end (such as an optical fiber probe) of the spectral analyzer (14) is inserted into a sampling port specially arranged on the side wall of the combustion chamber (11) for collecting the flame radiation spectrum and inverting the temperature field distribution. The gas sampling probe (12) is inserted into the gas outlet end or flue of the combustion chamber (11) for continuously extracting flue gas samples and connected to a gas analyzer or a computer (15) to realize real-time monitoring of the concentrations of pollutants such as CO and NOx.

[0012] The above precisely designed subsystems and their clear connection and cooperation relationship realize accurate simulation of non-premixed combustion conditions, active reinforcement of flame stability and synchronous and accurate detection of multi-parameter combustion characteristics.

[0013] Advantages:

[0014] 1. Precise simulation of non-premixed combustion conditions by independent control of fuel and oxidant flow rates through proportional control valves;

[0015] 2. Gradient porosity porous media burner can simulate actual working conditions and enhance flame stability;

[0016] 3. High-speed camera, spectrum analyzer and gas sampling probe work together to realize synchronous monitoring of flame shape, temperature and pollutants;

[0017] BRIEF DESCRIPTION OF DRAWINGS Figure 1 It is a whole structure schematic view of the utility model; Figure 2 It is a porous media burner section view of the utility model; Figure 3 It is a flame stabilizer structure schematic view of the utility model;

[0018] Figure 4 It is a flow equalizing grid schematic view of the utility model. Figure 5 It is a fuel supply system schematic view of the utility model.

[0019] Figure 6 It is an oxidant supply system schematic view of the utility model.

[0020] Figure 7 It is a detection system schematic view of the utility model. DETAILED DESCRIPTION

[0021] Combining the attached Figure 1 , the fuel supply system is transported to the fuel delivery pipe (8) from the fuel tank (6) through the booster pump (7), and the flowmeter (5) and the proportional control valve (4) control the fuel flow in real time, and the flow equalizer (3) ensures that the airflow is uniformly entered into the combustion chamber (11). The oxidant supply system provides air through the air blower (1), heats it through the preheater (2), and then continues to flow through the flow equalizer (3) to ensure that the airflow is uniformly entered into the combustion chamber (11).

[0022] The porous media burner (9) is stacked with four layers of porous ceramic plates (18) inside, and the porosity increases from 30% at the inlet end to 60% at the outlet end ( Figure 2 ). The quartz observation window is provided on the side wall of the combustion chamber (11), and the high-speed camera (13) records the flame dynamics. The spectrum analyzer (14) collects the combustion radiation spectrum through the optical fiber probe, and inverts the temperature field distribution. The gas sampling probe (12) guides the flue gas into the computer (15) for flue gas analysis, and displays the CO and NOx concentrations in real time ( Figure 7 ).

[0023] During the experiment, the proportional control valve (4) is adjusted to set the fuel and air flow ratio, and after ignition, the non-premixed flame is stably burned in the porous media.

Claims

1. A porous media burner non-premixed flame test apparatus characterized by, The application relates to a fuel cell, which comprises a fuel supply system, an oxidant supply system, a detection system, a combustion chamber (11) and a porous medium burner (9), the fuel inlet end of the combustion chamber (11) is independently fluidly communicated with the fuel supply system and the oxidant supply system respectively, the porous medium burner (9) is fixed in the combustion chamber (11) and is composed of a stack of porous ceramic plates (18) with multilayer gradient porosity; fuel and oxidant enter the combustion chamber (11) through fuel independent delivery channels and oxidant independent delivery channels respectively and are mixed and combusted in the porous medium burner (9); the combustion product outlet end of the combustion chamber (11) is fluidly communicated with the detection system, the porous medium burner (9) is provided with a flame stabilizer (20), the fuel supply system and the oxidant supply system are both provided with proportional regulating valves (4) for independently regulating the flow ratio of fuel and oxidant.

2. The porous media burner non-premixed flame test apparatus of claim 1, wherein, The fuel supply system comprises a fuel storage tank (6), a fuel booster pump (7) and a fuel delivery pipe (8), the fuel delivery pipe (8) is sequentially provided with a flow equalizer (3), a proportional regulating valve (4) and a flowmeter (5) for monitoring fuel flow, the flow equalizer (3) is a honeycomb-shaped air flow distribution structure arranged in the oxidant delivery pipe (16), and the outlet end of the fuel delivery pipe (8) is sealingly connected with the fuel inlet of the combustion chamber (11) through a flange between the fuel delivery pipe and the combustion chamber inlet.

3. The porous media burner non-premixed flame test apparatus of claim 1, wherein, The oxidant supply system comprises a blower (1), a gas preheater (2) and an oxidant delivery pipe (16), the oxidant delivery pipe (16) is sequentially provided with a flowmeter (5) and a proportional regulating valve (4), and the outlet end of the oxidant delivery pipe (16) is connected with the oxidant inlet of the combustion chamber (11) through a corrugated pipe.

4. The porous media burner non-premixed flame test apparatus of claim 1, wherein, The porous medium burner (9) comprises an outer shell (17) and internally-stacked porous ceramic plates (18), the porosity of the porous ceramic plates (18) increases from 30% to 60% along the air flow direction, and the adjacent ceramic plates are fixed through high-temperature-resistant adhesive; the side wall of the outer shell (17) is embedded with a quartz observation window (19) for optical detection.

5. The porous media burner non-premixed flame test apparatus of claim 4, wherein, The flame stabilizer (20) is a porous metal disc, which is fixed at the outlet end of the porous medium burner (9) and is uniformly provided with micropores with a diameter of 2-5 mm on the surface.

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