Flow field visualization detection apparatus and method for flow batteries

Abstract

The application discloses a liquid flow battery flow field visualization detection device and method, which comprises a camera, a visualization pool and a flow component. The visualization pool comprises a flow channel plate, a sealing element, a porous electrode, a temperature-sensitive color-changing liquid crystal sheet, a transparent observation plate and a plurality of fixing elements for fastening the visualization pool. The camera is arranged above the transparent observation plate, and the flow component is arranged on one side of the visualization pool and connected with the visualization pool to control the temperature and flow rate of the fluid flowing into the visualization pool. The liquid flow battery flow field visualization detection device and method provided by the application aims to realize in-situ visualization of the flow field by monitoring the temperature distribution of the porous electrode surface in contact with the fluid in real time and characterizing the fluid distribution state in the porous electrode.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of liquid flow battery energy storage, in particular to a liquid flow battery flow field visualization detection device and method. BACKGROUND

[0002] In the prior art, numerical simulation (such as computational fluid dynamics) technology is used to understand the flow behavior of electrolyte in complex flow channels. However, the current simulation method often ignores too much details of the flow field and is not accurate enough for simplifying calculation or limited by model precision. For example, the accurate prediction ability of key phenomena such as local dead zone, vortex, uneven velocity distribution in the flow channel is limited, and it is difficult to fully reflect the complex fluid dynamics behavior under real working conditions, which leads to the simulation results being limited in guiding the actual flow field design.

[0003] Compared with numerical simulation, direct experimental methods can better reflect the flow field situation under real operating conditions. However, existing flow field experimental methods, such as particle image velocimetry, usually require special transparent battery structure, expensive equipment and specific tracer particles, and the operation is complex, and it is difficult to carry out in actual battery materials and real electrochemical reaction environment, and the practicability is greatly limited.

[0004] Therefore, how to provide a liquid flow battery flow field visualization detection device, which can intuitively and effectively reveal the fluid distribution state in the flow field, so as to realize the in-situ visualization of the flow field, has become a problem to be solved. SUMMARY

[0005] The present application provides a liquid flow battery flow field visualization detection device and method, which aims to characterize the fluid distribution state inside the porous electrode by monitoring the temperature distribution of the porous electrode surface in contact with the fluid in real time, so as to realize the in-situ visualization of the flow field.

[0006] In one aspect, the embodiments of the present application provide a flow field visualization detection device for liquid flow battery, comprising: a camera, a visualization cell and a flow assembly, the visualization cell comprising: a flow channel plate, a sealing element, a porous electrode, a thermochromic liquid crystal sheet, a transparent observation plate and a plurality of fixing elements, the flow channel plate is provided with a flow channel and a plurality of first through holes, the center area of the flow channel plate is provided with an electrode area, and a plurality of first through holes are arranged around the electrode area; the sealing element is arranged above the flow channel plate, the sealing element is provided with an opening area and a plurality of second through holes, the opening area is concentrically arranged with the electrode area, and the second through holes are concentrically arranged with the first through holes; the porous electrode is arranged above the opening area and the electrode area; the thermochromic liquid crystal sheet is arranged above the sealing element, the thermochromic liquid crystal sheet is provided with a plurality of third through holes, and the third through holes are concentrically arranged with the second through holes; the transparent observation plate is arranged above the thermochromic liquid crystal sheet, the transparent observation plate is provided with a plurality of fourth through holes, and the fourth through holes are concentrically arranged with the third through holes; any one of the plurality of fixing elements is used to pass through the concentrically arranged fourth through holes, third through holes, second through holes and first through holes to fasten the visualization cell; wherein the camera is arranged above the transparent observation plate, and the flow assembly is arranged on one side of the visualization cell and connected with the visualization cell to control the temperature and flow rate of the fluid flowing into the visualization cell.

[0007] Optionally, in some embodiments of the present application, the fluid includes a cold fluid and a hot fluid, the temperature of the cold fluid ranges from 25 degrees to 30 degrees, and the temperature of the hot fluid ranges from 40 degrees to 45 degrees.

[0008] Optionally, in some embodiments of the present application, the flow rate ranges from 45 milliliters per minute to 55 milliliters per minute.

[0009] Optionally, in some embodiments of the present application, the type of the flow channel is a finger-shaped flow channel, and the width of the finger-shaped flow channel ranges from 2.5 millimeters to 3.5 millimeters.

[0010] Optionally, in some embodiments of the present application, the length of the flow channel plate, the length of the sealing element, the length of the thermochromic liquid crystal sheet and the length of the transparent observation plate are the same; the width of the flow channel plate, the width of the sealing element, the width of the thermochromic liquid crystal sheet and the width of the transparent observation plate are the same.

[0011] Optionally, in some embodiments of the present application, the length of the flow channel plate and the width of the flow channel plate are equal, and the length of the flow channel plate ranges from 130 millimeters to 150 millimeters.

[0012] Optionally, in some embodiments of the present application, the thickness of the flow channel plate and the thickness of the transparent observation plate are the same, the thickness of the thermochromic liquid crystal sheet is the same as the thickness of the seal, the thickness of the flow channel plate is greater than the thickness of the porous electrode, and the thickness of the porous electrode is greater than the thickness of the seal.

[0013] Optionally, in some embodiments of the present application, the thickness of the flow channel plate ranges from 14 mm to 18 mm, the thickness of the porous electrode ranges from 1 mm to 3 mm, and the thickness of the thermochromic liquid crystal sheet ranges from 0.3 mm to 0.7 mm.

[0014] Optionally, in some embodiments of the present application, the length of the electrode area is equal to the length of the opening area, the width of the electrode area is equal to the width of the opening area, and the length of the electrode area is greater than the width of the electrode area.

[0015] Optionally, in some embodiments of the present application, the length of the electrode area ranges from 68 mm to 74 mm, and the difference between the length of the electrode area and the width of the electrode area ranges from 1 mm to 3 mm.

[0016] Optionally, in some embodiments of the present application, the flow assembly comprises: a first pipe, a second pipe, a flow control pump, a first three-way valve, a second three-way valve, a first cold fluid valve, a second cold fluid valve, a first hot fluid valve, a second hot fluid valve, a cold fluid tank, and a hot fluid tank; the input end of the first pipe is connected with the outlet of the visualization tank, and the output end of the first pipe is connected with the input end of the first three-way valve; the second pipe comprises a first branch pipe, a second branch pipe, and a third branch pipe, the input end of the first branch pipe is connected with the first output end of the first three-way valve, the input end of the second branch pipe is connected with the second output end of the first three-way valve, the output end of the first branch pipe is connected with the first input end of the second three-way valve, the output end of the second branch pipe is connected with the second input end of the second three-way valve, the input end of the third branch pipe is connected with the output end of the second three-way valve, and the output end of the third branch pipe is connected with the inlet of the visualization tank; the first branch pipe is further provided with the first hot fluid valve, the hot fluid tank, and the second hot fluid valve, the first hot fluid valve is arranged between the input end of the first branch pipe and the hot fluid tank, and is used for controlling the flow rate of the fluid flowing into the hot fluid tank; the second hot fluid valve is arranged between the output end of the first branch pipe and the hot fluid tank, and is used for controlling the flow rate of the fluid flowing out of the hot fluid tank; the second branch pipe is further provided with the first cold fluid valve, the cold fluid tank, and the second cold fluid valve, the first cold fluid valve is arranged between the input end of the second branch pipe and the cold fluid tank, and is used for controlling the flow rate of the fluid flowing into the cold fluid tank; the second cold fluid valve is arranged between the output end of the second branch pipe and the cold fluid tank, and is used for controlling the flow rate of the fluid flowing out of the cold fluid tank; and the flow control pump is arranged between the output end of the second three-way valve and the visualization tank, the fluid flowing out of the output end of the second three-way valve flows into the visualization tank through the flow control pump, and the flow control pump is used for controlling the flow rate of the fluid.

[0017] Optionally, in some embodiments of the present application, the diameters of the first pipe and the second pipe are equal.

[0018] Optionally, in some embodiments of the present application, the diameters of the first pipe and the second pipe are equal.

[0019] Optionally, in some embodiments of the present application, the flow channel plate and the transparent observation plate are made of a material with a low thermal conductivity.

[0020] In another aspect, the application provides a flow field visualization detection method for a flow battery, which uses the flow field visualization detection device for a flow battery as described above, and includes the following steps: setting the flow rate of the flow control pump and the temperature of the fluid; recording the temperature distribution data of the visualization pool within a preset time through the camera; calculating the uniformity coefficient set of the temperature distribution within the preset time according to the temperature distribution data; and determining whether the flow field distribution uniformity of the porous electrode within the preset time meets the requirements according to the uniformity coefficient set.

[0021] Compared with the prior art, the flow field visualization detection device and method for a flow battery provided by the application can control the fluid at a preset temperature to flow into the visualization pool through the flow assembly, thereby actively establishing a background temperature field inside the visualization pool, so that the local temperature change caused by the flow rate difference of the fluid can be observed through the camera and the temperature change image can be collected. The application takes advantage of the characteristic that temperature is easy to measure in situ and non-invasively, and the temperature distribution on the surface of the porous electrode in contact with the fluid is monitored in real time to represent the fluid distribution state inside the porous electrode, thereby realizing in-situ visualization of the flow field. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a schematic diagram of the flow field visualization detection device for a flow battery provided by the application;

[0023] Figure 2 is a schematic diagram of the visualization pool provided by the application;

[0024] Figure 3 is a color distribution diagram of the temperature-sensitive color-changing liquid crystal sheet photographed by the camera in the flow field visualization detection device for a flow battery provided by the application at different times;

[0025] Figure 4 is a flowchart of the flow field visualization detection method for a flow battery provided by the application. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the application will be described below with reference to the drawings in the embodiments of the application. The described technical solutions are only used to explain and illustrate the idea of the application, and should not be regarded as a limitation on the protection scope of the application.

[0027] The various embodiments provided by the application are similar, and the features in different embodiments can be combined with each other.

[0028] As shown in Figure 1 The embodiments of the application provide a flow field visualization detection device 100 for a flow battery, which includes a camera 101, a visualization pool 102, and a flow assembly 103.

[0029] As shown in Figure 2As shown, the visualization cell 102 comprises a flow channel plate 10, a seal 20, a porous electrode 30, a thermochromic liquid crystal sheet 40, a transparent observation plate 50, and a plurality of fasteners 60.

[0030] In the embodiment of the present application, the flow channel plate 10 is provided with a flow channel 11 and a plurality of first through holes 12, and a center region of the flow channel plate 10 is provided with an electrode region 13, and the plurality of first through holes 12 are arranged around the electrode region 13. The flow channel 11 is used to guide the flow of fluid.

[0031] In the embodiment of the present application, the seal 20 is arranged above the flow channel plate 10, and the seal 20 is provided with an opening region 21 and a plurality of second through holes 22, and the opening region 21 is concentrically arranged with the electrode region 13, and the second through holes 22 are concentrically arranged with the first through holes 12. Specifically, the seal 20 is a fluorine rubber gasket. The fluorine rubber gasket covers the flow channel plate 10. The cross-sectional shape of the fluorine rubber gasket is the same as that of the flow channel plate 10.

[0032] In the embodiment of the present application, the porous electrode 30 is arranged in the opening region 21 and above the electrode region 13. Specifically, the porous electrode 30 adopts graphite felt, which is used to permeate fluid.

[0033] In the embodiment of the present application, the thermochromic liquid crystal sheet 40 is arranged above the seal 20, and the thermochromic liquid crystal sheet 40 is provided with a plurality of third through holes 41, and the third through holes 41 are concentrically arranged with the second through holes 22. Specifically, the thermochromic liquid crystal sheet 40 covers the porous electrode 30, and can display different colors according to the temperature change of the contact surface.

[0034] In the embodiment of the present application, the transparent observation plate 50 is arranged above the thermochromic liquid crystal sheet 40, and the transparent observation plate 50 is provided with a plurality of fourth through holes 51, and the fourth through holes 51 are concentrically arranged with the third through holes 41. Specifically, the transparent observation plate 50 is made of high-transparency acrylic plate. The transparent observation plate 50 covers the thermochromic liquid crystal sheet 40, and is used to observe the color change of the thermochromic liquid crystal sheet 40, and serves as one of the sealing plates of the visualization cell 102.

[0035] In the embodiment of the present application, any one of the plurality of fasteners 60 is used to pass through the concentrically arranged fourth through holes 51, third through holes 41, second through holes 22 and first through holes 12, so as to fasten the visualization cell 102. Specifically, the fastener 60 comprises a bolt and a nut, the bolt is used to pass through the concentrically arranged fourth through holes 51, third through holes 41, second through holes 22 and first through holes 12, and the nut is used to fasten the flow channel plate 10, the seal 20, the thermochromic liquid crystal sheet 40 and the transparent observation plate 50 together, so as to form a sealed fluid chamber.

[0036] The camera 101 is arranged above the transparent observation plate 50, and the flow assembly 103 is arranged on one side of the visualization tank 102 and connected with the visualization tank 102, so as to control the temperature and flow rate of the fluid flowing into the visualization tank 102.

[0037] The liquid flow battery flow field visualization detection device provided in the application can control the fluid at a preset temperature to flow into the visualization tank 102, so as to actively establish a background temperature field in the visualization tank 102, thereby facilitating the observation of the local temperature change caused by the flow rate difference of the fluid by the camera 101 and the collection of the temperature change image. The application utilizes the characteristic that the temperature is easy to measure in situ and non-invasively, and the surface temperature distribution of the porous electrode 30 in contact with the fluid is monitored in real time, so as to represent the fluid distribution state in the porous electrode 30, thereby realizing the in-situ visualization of the flow field.

[0038] As shown in Figure 1 The flow assembly 103 comprises a first pipeline 1a, a second pipeline 1b, a flow control pump 2, a first three-way valve 3a, a second three-way valve 3b, a first cold fluid valve 4a, a second cold fluid valve 4b, a first hot fluid valve 5a, a second hot fluid valve 5b, a cold fluid tank 6, and a hot fluid tank 7.

[0039] The input end of the first pipeline 1a is connected with the outlet of the visualization tank 102, and the output end of the first pipeline 1a is connected with the input end of the first three-way valve 3a.

[0040] The second pipeline 1b comprises a first branch pipeline 01, a second branch pipeline 02, and a third branch pipeline 03. The input end of the first branch pipeline 01 is connected with the first output end of the first three-way valve 3a, the input end of the second branch pipeline 02 is connected with the second output end of the first three-way valve 3a, the output end of the first branch pipeline 01 is connected with the first input end of the second three-way valve 3b, the output end of the second branch pipeline 02 is connected with the second input end of the second three-way valve 3b, the input end of the third branch pipeline 03 is connected with the output end of the second three-way valve 3b, and the output end of the third branch pipeline 03 is connected with the inlet of the visualization tank 102.

[0041] The first hot fluid valve 5a, the hot fluid tank 7, and the second hot fluid valve 5b are further arranged on the first branch pipeline 01.

[0042] The first hot fluid valve 5a is arranged between the input end of the first branch pipeline 01 and the hot fluid tank 7, and is used for controlling the flow rate of the fluid flowing into the hot fluid tank 7.

[0043] The second hot fluid valve 5b is arranged between the output end of the first branch pipeline 01 and the hot fluid tank 7, and is used for controlling the flow rate of the fluid flowing out of the hot fluid tank 7.

[0044] The second branch pipeline 02 is further provided with a first cold fluid valve 4a, a cold fluid tank 6 and a second cold fluid valve 4b.

[0045] The first cold fluid valve 4a is arranged between the input end of the second branch pipeline 02 and the cold fluid tank 6, and is used to control the flow rate of the fluid flowing into the cold fluid tank 6.

[0046] The second cold fluid valve 4b is arranged between the output end of the second branch pipeline 02 and the cold fluid tank 6, and is used to control the flow rate of the fluid flowing out of the cold fluid tank 6.

[0047] The flow control pump 2 is arranged between the output end of the second three-way valve 3b and the visualization pool 102, and the fluid flowing out of the output end of the second three-way valve 3b flows into the visualization pool 102 after passing through the flow control pump 2, and the flow control pump 2 is used to control the flow rate of the fluid.

[0048] In the embodiments of the present application, the diameters of the first pipeline 1a and the second pipeline 1b are equal.

[0049] In the embodiments of the present application, the diameters of the first pipeline 1a and the second pipeline 1b are equal.

[0050] In the embodiments of the present application, the number of the first through holes 12, the second through holes 22, the third through holes 41 and the fourth through holes 51 is equal, and the number of the first through holes 12 on any side of the electrode area 13 is equal. For example, the flow channel plate 10 is square, and the number of the first through holes 12 on any side of the electrode area 13 is 3.

[0051] Further, the plurality of first through holes 12 on any side of the electrode area 13 are uniformly distributed. For example, the number of the first through holes 12 on any side of the electrode area 13 is 3, of which two first through holes 12 are respectively located at two corners of the side, and the other is located at the middle position of the side. The number of the first through holes 12 on any side of the electrode area 13 can also be a positive integer greater than 3, such as 4, 5, 6, etc.

[0052] In the embodiments of the present application, the shape of the flow channel plate 10 is square, and the shapes of the cross sections of the electrode area 13 and the opening area 21 are both square.

[0053] In the embodiments of the present application, the fluid includes a cold fluid and a hot fluid, the temperature of the cold fluid ranges from 25 degrees (℃) to 30 degrees (℃), and the temperature of the hot fluid ranges from 40 degrees to 45 degrees. Specifically, the temperature of the cold fluid includes 25 degrees, 26 degrees, 27 degrees, 28 degrees, 29 degrees, and 30 degrees. The temperature of the hot fluid includes 40 degrees, 41 degrees, 42 degrees, 43 degrees, 44 degrees, and 45 degrees. Preferably, the temperature of the cold fluid is 30 degrees, and the temperature of the hot fluid is 40 degrees. Those skilled in the art can adjust according to actual conditions, and the above values can be arbitrarily combined.

[0054] In the embodiments of the present application, the flow rate ranges from 45 milliliters per minute (ml / min) to 55 milliliters per minute (ml / min). The flow rate includes 45 milliliters per minute, 46 milliliters per minute, 47 milliliters per minute, 48 milliliters per minute, 49 milliliters per minute, 50 milliliters per minute, 51 milliliters per minute, 52 milliliters per minute, 53 milliliters per minute, 54 milliliters per minute, and 55 milliliters per minute. Preferably, the flow rate is 50 milliliters per minute.

[0055] In the embodiments of the present application, the flow channel 11 is a finger-shaped flow channel 11, and the width of the finger-shaped flow channel 11 ranges from 2.5 millimeters (mm) to 3.5 millimeters (mm). The width of the finger-shaped flow channel 11 includes 2.5 millimeters, 2.6 millimeters, 2.7 millimeters, 2.8 millimeters, 2.9 millimeters, 3 millimeters, 3.1 millimeters, 3.2 millimeters, 3.3 millimeters, 3.4 millimeters, and 3.5 millimeters. Preferably, the width of the finger-shaped flow channel 11 is 3 millimeters. It is verified by experiments that the finger-shaped flow channel 11 with a width of 3 millimeters reaches the temperature uniform state fastest, and accordingly, it can greatly improve the fluid updating speed and flow field uniformity in the porous electrode 30.

[0056] In the embodiments of the present application, the length of the flow channel plate 10, the length of the sealing member 20, the length of the temperature-sensitive discoloration liquid crystal sheet 40, and the length of the transparent observation plate 50 are all the same. The width of the flow channel plate 10, the width of the sealing member 20, the width of the temperature-sensitive discoloration liquid crystal sheet 40, and the width of the transparent observation plate 50 are all the same.

[0057] In the embodiments of the present application, the length of the flow channel plate 10 and the width of the flow channel plate 10 are equal, and the length of the flow channel plate 10 ranges from 130 millimeters to 150 millimeters. The length of the flow channel plate 10 includes 130 millimeters, 135 millimeters, 140 millimeters, 145 millimeters, and 150 millimeters. Preferably, the length and the width of the flow channel plate 10 are both 140 millimeters.

[0058] In the embodiment of the present application, the thickness of the flow channel plate 10 and the thickness of the transparent observation plate 50 are the same, the thickness of the thermochromic liquid crystal sheet 40 and the thickness of the sealing member 20 are the same, the thickness of the flow channel plate 10 is greater than the thickness of the porous electrode 30, and the thickness of the porous electrode 30 is greater than the thickness of the sealing member 20.

[0059] In the embodiment of the present application, the thickness of the flow channel plate 10 ranges from 14 mm to 18 mm. The thickness of the flow channel plate 10 includes 14 mm, 15 mm, 16 mm, 17 mm, and 18 mm. Preferably, the thickness of the flow channel plate 10 is 16 mm.

[0060] In the embodiment of the present application, the thickness of the porous electrode 30 ranges from 1 mm to 3 mm. The thickness of the porous electrode 30 includes 1 mm, 1.5 mm, 2 mm, 2.5 mm, and 3 mm. Preferably, the thickness of the porous electrode 30 is 2 mm.

[0061] In the embodiment of the present application, the thickness of the thermochromic liquid crystal sheet 40 ranges from 0.3 mm to 0.7 mm. The thickness of the thermochromic liquid crystal sheet 40 includes 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, and 0.7 mm. Preferably, the thickness of the thermochromic liquid crystal sheet 40 is 0.5 mm.

[0062] In the embodiment of the present application, the length of the electrode area 13 is equal to the length of the opening area 21, the width of the electrode area 13 is equal to the width of the opening area 21, and the length of the electrode area 13 is greater than the width of the electrode area 13.

[0063] In the embodiment of the present application, the length of the electrode area 13 ranges from 68 mm to 74 mm. Specifically, the length of the electrode area 13 includes 68 mm, 69 mm, 70 mm, 71 mm, 72 mm, 73 mm, and 74 mm. Preferably, the length of the electrode area 13 is 71 mm.

[0064] In the embodiment of the present application, the difference between the length of the electrode area 13 and the width of the electrode area 13 ranges from 1 mm to 3 mm. Specifically, the difference between the length of the electrode area 13 and the width of the electrode area 13 includes 1 mm, 1.5 mm, 2 mm, 2.5 mm, and 3 mm. Preferably, the difference between the length of the electrode area 13 and the width of the electrode area 13 is 1 mm. Preferably, the width of the electrode area 13 is 70 mm.

[0065] In the embodiments of this application, the flow channel plate 10 and the transparent observation plate 50 are made of materials with low thermal conductivity. Specifically, in order to enhance the mapping relationship between flow rate and temperature change, preferably, the flow channel plate 10 and the transparent observation plate 50 of the visualization pool 102 are made of materials with low thermal conductivity to reduce heat loss to the surrounding environment through solid conduction, making convective heat transfer between the fluid and the electrodes the dominant heat transfer mode. By controlling the fluid flow rate and temperature difference, the visualization effect can be optimized.

[0066] Specifically, the cold fluid circulates throughout the system, flowing through the flow channel 11 and porous electrode 30 within the visualization pool 102 until a relatively stable initial temperature is reached within the visualization pool 102. Then, the hot fluid, guided by the flow channel 11, enters the porous electrode 30, where it undergoes convective heat transfer with the cold fluid remaining in the flow channel 11 and the porous electrode 30. Due to the varying local flow velocities of the hot fluid within the porous electrode 30, differences in convective heat transfer rates occur in different regions of the porous electrode 30, resulting in a temperature distribution on the surface of the porous electrode 30 in contact with the thermochromic liquid crystal panel 40. The thermochromic liquid crystal panel 40 responds to this temperature distribution by displaying a corresponding color pattern. A camera 101 is used to record the process of color change on the thermochromic liquid crystal panel 40 over time, or to record a video of the color distribution at a specific moment.

[0067] By identifying color uniformity, differences in color change rates, and the presence of regions where the color remains unchanged for extended periods, the uniformity of the flow field distribution can be determined, and potential "dead zones" of slow or stagnant flow can be located.

[0068] like Figure 3 As shown, frames are extracted from the observed video to obtain different times (e.g., ...). Figure 3 The image shows color images of the temperature distribution at the 10th, 30th, 50th, 70th, and 90th seconds. The images are cropped to retain only the effective observation area of ​​the thermochromic liquid crystal display (TCLCD). Since the TLCD 40 gradually changes from black to blue as the temperature increases, to facilitate a quantitative assessment of the temperature distribution uniformity, the blue values ​​in the color images are statistically calculated, and the uniformity coefficient of the blue color within the image is calculated using an image processing program.

[0069] This value quantifies the uniformity of temperature distribution (a higher value indicates greater uniformity). By analyzing the relationship between this uniformity index and time, the homogenization process can be assessed. Ultimately, using this temperature field uniformity and evolution data, the uniformity of the flow field inside the electrode can be evaluated, and flow velocity-related characteristics can be indirectly inferred based on information such as the time to reach steady state.

[0070] That is, by setting the flow assembly 103 to control the cold fluid and the hot fluid to flow into the visualization pool 102 in sequence, a background temperature field is actively established inside the visualization pool 102, so as to facilitate the observation of the local temperature change caused by the flow rate difference of the hot fluid by the camera 101 and the collection of the temperature change image. The application utilizes the characteristic that temperature is easy to measure in situ and non-invasively, and by monitoring the surface temperature distribution of the porous electrode 30 in contact with the fluid in real time, the fluid distribution state inside the porous electrode 30 is characterized, so as to realize in-situ visualization of the flow field.

[0071] As shown in Figure 4 The application provides a liquid flow battery flow field visualization detection method, which adopts the liquid flow battery flow field visualization detection device as described above, and comprises the following steps:

[0072] S11, set the flow rate of the flow control pump and the temperature of the fluid.

[0073] S12, record the temperature distribution data of the visualization pool in a preset time by the camera.

[0074] S13, calculate the uniformity coefficient set of the temperature distribution in the preset time according to the temperature distribution data.

[0075] S14, judge whether the flow field distribution uniformity of the porous electrode in the preset time meets the requirements according to the uniformity coefficient set.

[0076] The liquid flow battery flow field visualization detection method provided by the application controls the fluid at a preset temperature to flow into the visualization pool inside by setting the flow assembly, so as to actively establish a background temperature field inside the visualization pool, so as to facilitate the observation of the local temperature change caused by the flow rate difference of the fluid by the camera and the collection of the temperature change image. The application utilizes the characteristic that temperature is easy to measure in situ and non-invasively, and by monitoring the surface temperature distribution of the porous electrode in contact with the fluid in real time, the fluid distribution state inside the porous electrode is characterized, so as to realize in-situ visualization of the flow field.

[0077] The above describes a liquid flow battery flow field visualization detection device and method input by the embodiment of the application in detail, and the above embodiment description is only for helping to understand the core idea of the application, and the above description should not be understood as limiting the protection scope of the application.

Claims

1. A flow field visualization detection device for a flow battery, the device comprising: The application relates to a temperature visualizing device, which comprises a camera, a visualizing pool and a flow assembly. The visualizing pool comprises a flow channel plate provided with flow channels and a plurality of first through holes, a central area of the flow channel plate is provided with an electrode area, and a plurality of the first through holes are arranged around the electrode area; a sealing member arranged above the flow channel plate, the sealing member being provided with an opening area and a plurality of second through holes, the opening area being concentrically arranged with the electrode area, and the second through holes being concentrically arranged with the first through holes; a porous electrode arranged in the opening area and above the electrode area; a thermochromic liquid crystal sheet arranged above the sealing member, the thermochromic liquid crystal sheet being provided with a plurality of third through holes, and the third through holes being concentrically arranged with the second through holes; a transparent observation plate arranged above the thermochromic liquid crystal sheet, the transparent observation plate being provided with a plurality of fourth through holes, and the fourth through holes being concentrically arranged with the third through holes; a plurality of fixing members, any of the fixing members being used for penetrating the concentrically arranged fourth through holes, third through holes, second through holes and first through holes to fasten the visualizing pool; wherein the camera is arranged above the transparent observation plate, and the flow assembly is arranged on one side of the visualizing pool and connected with the visualizing pool to control the temperature and flow rate of the fluid flowing into the visualizing pool; the fluid comprises cold fluid and hot fluid, the temperature of the cold fluid ranges from 25 DEG C to 30 DEG C, and the temperature of the hot fluid ranges from 40 DEG C to 45 DEG C; the flow assembly comprises a first pipeline, a second pipeline, a flow control pump, a first three-way valve, a second three-way valve, a first cold fluid valve, a second cold fluid valve, a first hot fluid valve, a second hot fluid valve, a cold fluid tank and a hot fluid tank; the input end of the first pipeline is connected with the outlet of the visualizing pool, and the output end of the first pipeline is connected with the input end of the first three-way valve; the second pipeline comprises a first branch pipeline, a second branch pipeline and a third branch pipeline, the input end of the first branch pipeline is connected with the first output end of the first three-way valve, the input end of the second branch pipeline is connected with the second output end of the first three-way valve, the output end of the first branch pipeline is connected with the first input end of the second three-way valve, the output end of the second branch pipeline is connected with the second input end of the second three-way valve, the input end of the third branch pipeline is connected with the output end of the second three-way valve, and the output end of the third branch pipeline is connected with the inlet of the visualizing pool; the first branch pipeline is further provided with a first hot fluid valve, a hot fluid tank and a second hot fluid valve, the first hot fluid valve is arranged between the input end of the first branch pipeline and the hot fluid tank and is used for controlling the flow rate of the fluid flowing into the hot fluid tank, and the second hot fluid valve is arranged between the output end of the first branch pipeline and the hot fluid tank and is used for controlling the flow rate of the fluid flowing out of the hot fluid tank. ​ ​ The second branch pipeline is further provided with a first cold fluid valve, a cold fluid tank and a second cold fluid valve. The first cold fluid valve is arranged between the input end of the second branch pipeline and the cold fluid tank, and is used for controlling the flow of the fluid flowing into the cold fluid tank. The second cold fluid valve is arranged between the output end of the second branch pipeline and the cold fluid tank, and is used for controlling the flow of the fluid flowing out of the cold fluid tank. The flow control pump is arranged between the output end of the second three-way valve and the visualization tank. The fluid flowing out of the output end of the second three-way valve flows into the visualization tank through the flow control pump. The flow control pump is used for controlling the flow rate of the fluid. The flow channel assembly is used for allowing the cold fluid to flow through the flow channel and the porous electrode in the visualization tank until the initial temperature state is reached in the visualization tank, and then allowing the hot fluid to enter the porous electrode under the guidance of the flow channel, so that the hot fluid and the cold fluid remaining in the flow channel and the porous electrode are subjected to convection heat exchange, so as to form a temperature distribution on the surface of the porous electrode in contact with the temperature-sensitive color-changing liquid crystal sheet. The camera is used for collecting color images of the color change process of the temperature-sensitive color-changing liquid crystal sheet. The blue value in the color image is statistically calculated, and the uniformity coefficient of the blue value is calculated through an image processing program. The uniformity coefficient is used to evaluate the uniformity of the flow field in the visualization tank according to the change relationship of the uniformity coefficient with time.

2. The flow field visualization detection device of claim 1, wherein, The flow rate is in the range of 45-55 ml / min.

3. The flow field visualization detection device of claim 1, wherein, The flow channel is a finger-shaped flow channel, and the width of the finger-shaped flow channel is in the range of 2.5-3.5 mm.

4. The flow field visualization detection device of claim 1, wherein, The length of the flow channel plate, the length of the sealing member, the length of the temperature-sensitive color-changing liquid crystal sheet and the length of the transparent observation plate are the same. The width of the flow channel plate, the width of the sealing member, the width of the temperature-sensitive color-changing liquid crystal sheet and the width of the transparent observation plate are the same.

5. The flow field visualization detection device of claim 4, wherein, The length of the flow channel plate is equal to the width of the flow channel plate, and the length of the flow channel plate is in the range of 130-150 mm.

6. The flow field visualization detection device of claim 1, wherein, The thickness of the flow channel plate is the same as the thickness of the transparent observation plate, the thickness of the temperature-sensitive color-changing liquid crystal sheet is the same as the thickness of the sealing member, the thickness of the flow channel plate is greater than the thickness of the porous electrode, and the thickness of the porous electrode is greater than the thickness of the sealing member.

7. The flow field visualization detection device of claim 6, wherein, The thickness of the flow channel plate is in the range of 14-18 mm, the thickness of the porous electrode is in the range of 1-3 mm, and the thickness of the temperature-sensitive color-changing liquid crystal sheet is in the range of 0.3-0.7 mm.

8. The flow field visualization detection device of claim 1, wherein, The length of the electrode area is equal to the length of the opening area, and the width of the electrode area is equal to the width of the opening area. The length of the electrode area is greater than the width of the electrode area.

9. The flow field visualization detection device of claim 8, wherein, The length of the electrode area is in the range of 68-74 mm, and the difference between the length of the electrode area and the width of the electrode area is in the range of 1-3 mm.

10. The flow field visualization detection device of claim 1, wherein, The first pipeline and the second pipeline have equal diameters.

11. The flow field visualization detection device of claim 1, wherein, The first pipeline and the second pipeline have diameters ranging from 3 mm to 5 mm.

12. The flow field visualization detection device of claim 1, wherein, The flow channel plate and the transparent observation plate are made of a material with a low thermal conductivity.

13. A method for flow field visualization detection of a flow battery, using the flow field visualization detection device according to any one of claims 1 to 12, characterized in that, The method comprises the following steps: Setting the flow rate of the flow control pump and the temperature of the fluid; Recording temperature distribution data of the visualization pool within a preset time through the camera; Calculating a set of uniformity coefficients of the temperature distribution within the preset time according to the temperature distribution data; Judging whether the multi-electrode flow field distribution uniformity within the preset time meets the requirements according to the set of uniformity coefficients.

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