Permeability testing method

Abstract

The invention provides a permeability test method. The permeability test method comprises the following steps: placing a test sample in a test cylinder; adding test liquid into the test cylinder, and keeping the liquid level height in the test cylinder unchanged; obtaining the volume flow rate of the test liquid seeping from the test sample; the permeability of the test sample is calculated according to the liquid level height, the volume flow, the cross section area of the test sample and the thickness of the test sample, the cross section of the test sample is perpendicular to the length direction of the test cylinder, and the thickness is the size of the test sample in the length direction of the test cylinder. According to the permeability testing method provided by the invention, the technical problem of relatively low permeability testing accuracy in related technologies can be solved.

Description

Technical Field

[0001] The present application belongs to the technical field of permeability testing, and more specifically, to a permeability testing method. Background Art

[0002] When applying porous materials, it is usually necessary to know various performance indicators, such as permeability. Permeability is a key performance that affects the application of porous materials. Therefore, it is necessary to perform permeability testing on porous materials in order to facilitate the application of porous materials.

[0003] However, the permeability testing method in the related art has low accuracy. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a multi-permeability testing method to solve the technical problem of low accuracy of the permeability testing method in the related art.

[0005] To achieve the above purpose, the technical solution adopted in this application is:

[0006] A permeability testing method is provided, comprising:

[0007] Placing the test sample in the test cylinder;

[0008] Add test liquid into the test cylinder so that the liquid level in the test cylinder remains unchanged;

[0009] obtaining a volume flow rate of a test liquid seeping out of a test sample;

[0010] The permeability of the test sample is calculated based on the liquid level, volume flow rate, cross-sectional area of ​​the test sample and thickness of the test sample. The cross-sectional area of ​​the test sample is perpendicular to the length direction of the test cylinder, and the thickness is the dimension of the test sample along the length direction of the test cylinder.

[0011] Through the above technical solution, the permeability test method of the present application calculates the permeability of the test sample according to the liquid level, volume flow, cross-sectional area of ​​the test sample and thickness of the test sample. In addition, the permeability test method of the present application adds the test liquid to the test cylinder and keeps the liquid level in the test cylinder unchanged, so that the pressure of the test liquid remains unchanged during the permeability test of the test sample, which is conducive to improving the accuracy of the test results.

[0012] Therefore, the permeability testing method provided by the present application can solve the technical problem of low accuracy of permeability testing in related technologies.

[0013] In some embodiments, adding a test liquid into a test cylinder so that the liquid level in the test cylinder remains unchanged comprises:

[0014] Add test liquid to the test cylinder;

[0015] When the liquid level is higher than a preset height, the test liquid in the test cylinder is discharged to make the liquid level in the test cylinder reach the preset height.

[0016] In this way, the permeability testing method provided in the present application can keep the liquid level in the test tube unchanged, so that the pressure of the test liquid remains unchanged during the permeability testing of the test sample.

[0017] In some embodiments, when the liquid level is higher than a preset height, the test liquid in the test cylinder is discharged using a liquid outlet, wherein the liquid outlet is disposed on a side wall of the test cylinder, and a minimum distance between a side of the liquid outlet and the test sample is equal to the preset height.

[0018] In this way, when the liquid level is higher than the preset height, the test liquid can be discharged from the liquid outlet, so that the liquid level in the test cylinder remains unchanged, which is conducive to improving the accuracy of the test result.

[0019] In some embodiments, adding a test liquid to the test cartridge includes:

[0020] Use the liquid inlet to continuously add test liquid to the test cylinder.

[0021] In this way, the permeability testing method provided in the present application can continuously add test liquid to the test tube. When the liquid level is higher than a preset height, the test liquid can be discharged from the liquid outlet, so that the liquid level remains unchanged, which is conducive to improving the accuracy of the test results.

[0022] In some embodiments, the liquid inlet is disposed on a side wall of the test tube, and the minimum distance between the side of the liquid inlet and the test sample is greater than or equal to a preset height.

[0023] In this way, the test liquid can be prevented from flowing out of the liquid inlet. When the test liquid is added to the test cylinder through the liquid inlet, turbulence can be avoided to a certain extent inside the test liquid in the test cylinder to avoid affecting the test result.

[0024] In some embodiments, adding the test liquid to the test barrel further includes: adding the test liquid to the test barrel using a cache chamber, wherein the cache chamber is disposed in the test barrel and is connected to the liquid inlet, the cache chamber is provided with an overflow port, and the minimum distance between the side of the overflow port and the test sample is greater than or equal to a preset height.

[0025] In this way, the buffer chamber can buffer the test liquid added into the test cylinder through the liquid inlet, preventing the liquid entering the test cylinder through the liquid inlet from directly impacting the liquid surface in the test cylinder, causing the liquid surface height to change, thereby avoiding affecting the test result.

[0026] In some embodiments, the volume flow rate of the test liquid seeping out of the test sample is obtained after the liquid level in the test cylinder reaches a preset height and a first preset time has passed; or, the volume flow rate of the test liquid seeping out of the test sample is obtained after the liquid level in the test cylinder reaches a preset height and the seepage speed of the test liquid in the test cylinder stabilizes.

[0027] This can make the volume flow value more accurate.

[0028] In some embodiments, adding a test liquid into a test cylinder so that the liquid level in the test cylinder remains unchanged comprises:

[0029] Add test liquid into the test cylinder so that the liquid level in the test cylinder reaches a preset height;

[0030] When the liquid level is lower than the preset height, continue to add the test liquid into the test cylinder to make the liquid level in the test cylinder reach the preset height;

[0031] And / or, placing the test sample in the test cartridge comprises:

[0032] A watertight sealing material is provided at least on the periphery of the test sample;

[0033] Place the test sample in the test cylinder so that the sealing material abuts against the inner wall surface of the test cylinder.

[0034] In this way, leakage of the test liquid from the gap between the test sample and the inner wall surface of the test cylinder can be avoided.

[0035] In some embodiments, obtaining the volume flow rate of the test fluid permeated from the test sample includes:

[0036] measuring the volume of the test liquid that seeps out during the second preset time, and calculating the volume flow rate according to the volume and the second preset time;

[0037] Alternatively, the mass of the test liquid seeping out during the second preset time is measured, and the volume flow rate is calculated based on the mass and the second preset time.

[0038] Thus, the volume flow can be obtained by different methods.

[0039] In some embodiments,

[0040] Both ends of the test tube in the length direction are open;

[0041] and / or, repeatedly calculating the permeability of the test sample multiple times, and taking the average of the multiple calculation results as the permeability of the test sample;

[0042] And / or, the permeability of the test sample is K, and the calculation formula of K is:

[0043] K = -(u*μ*L) / △P, where u = Qv / S, △P = ρgh, Qv is the volume flow rate, S is the cross-sectional area of ​​the test sample, μ is the viscosity of the test liquid, L is the thickness of the test sample, ρ is the density of the test liquid, g is the acceleration of gravity, and h is the liquid level.

[0044] In this way, the permeability of the test sample can be calculated and the calculation results can be made more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0046] Figure 1 One of the flow charts of the permeability testing method provided in the embodiment of the present application;

[0047] Figure 2 A schematic diagram of the three-dimensional structure of a testing device used in the permeability testing method provided in an embodiment of the present application;

[0048] Figure 3 A schematic cross-sectional view of a test device used in the permeability test method provided in an embodiment of the present application;

[0049] Figure 4 for Figure 3 One of the partial enlarged views at A in the middle;

[0050] Figure 5 A schematic diagram of the structure of the test sample and the sealing material provided in the embodiment of the present application;

[0051] Figure 6 A schematic diagram of the top view of the test tube provided in an embodiment of the present application;

[0052] Figure 7 The second flow chart of the permeability testing method provided in the embodiment of the present application;

[0053] Figure 8 The third flow chart of the permeability testing method provided in the embodiment of the present application;

[0054] Fig. 9 for Figure 3 The second partial enlarged view of point A in the middle;

[0055] Fig.10 A fourth flow chart of the permeability testing method provided in an embodiment of the present application;

[0056] Fig.11 A schematic cross-sectional view of another testing device used in the permeability testing method provided in an embodiment of the present application;

[0057] Fig.12 This is a fifth flow chart of the permeability testing method provided in an embodiment of the present application.

[0058] Among them, the reference numerals in the figure are:

[0059] 100-test device; 1-test cylinder; 11-liquid inlet; 12-liquid outlet; 13-supporting part; 2-meter; 21-fourth liquid storage container; 22-weighing instrument; 3-test sample; 4-sealing material; 41-first sealing part; 42-second sealing part; 5-first liquid storage container; 51-liquid inlet pipe; 6-second liquid storage container; 61-liquid outlet pipe; 7-liquid guide pump; 71-liquid guide pipe; 8-third liquid storage container; 9-connecting pipe. DETAILED DESCRIPTION

[0060] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0061] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0062] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to 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 application.

[0063] 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0064] Porous materials generally have the advantages of low relative density, high specific strength, high specific surface area, light weight, sound insulation, heat insulation, good permeability, etc. Porous materials include porous ceramics, porous glass and porous membranes, etc. Porous materials have a wide range of uses. For example, porous ceramics can be used in the atomization core of the atomization device.

[0065] When applying porous materials, it is usually necessary to know various performance indicators, such as permeability. Permeability is a key performance that affects the application of porous materials. Therefore, it is necessary to perform permeability testing on porous materials. However, the accuracy of the permeability testing method in the related art is low, which affects the application of porous materials.

[0066] Please also read Figure 1 , Figure 2 , Figure 3 and Figure 4 , the permeability testing method provided in the embodiment of the present application is now described.

[0067] The permeability testing method provided in the embodiment of the present application comprises the following steps:

[0068] S1, placing the test sample 3 in the test cylinder 1.

[0069] Exemplarily, the test sample 3 may be made of a porous material. Exemplarily, the test sample 3 may be made of a porous ceramic. Exemplarily, the test sample 3 may be a sheet structure with uniform thickness.

[0070] It can be understood that a test device 100 used in the permeability test method provided in the embodiment of the present application includes a test tube 1 , and both ends of the test tube 1 in the length direction are open.

[0071] See also Figure 4 In some examples, the test cylinder 1 is placed vertically, that is, the length direction of the test cylinder 1 is consistent with the vertical direction. The test sample 3 may be close to the lower end of the test cylinder 1 .

[0072] See also Figure 5 In some examples, in step S1, placing the test sample 3 in the test cylinder 1 includes:

[0073] A water-tight sealing material 4 is provided at least on the peripheral surface of the test sample 3;

[0074] The test sample 3 is placed in the test cylinder 1 , so that the sealing material 4 abuts against the inner wall surface of the test cylinder 1 .

[0075] It is understandable that the sealing material 4 can be arranged on the circumference of the test sample 3. The sealing material 4 can also be arranged on the bottom surface of the test sample 3. For example, the sealing material 4 includes a first sealing portion 41 and a second sealing portion 42, the first sealing portion 41 is arranged on the circumference of the test sample 3, the second sealing portion 42 is arranged on the bottom surface of the test sample 3, and the first sealing portion 41 and the second sealing portion 42 are both annular. The first sealing portion 41 and the second sealing portion 42 can be connected as a whole, or the first sealing portion 41 and the second sealing portion 42 can be separated from each other.

[0076] Exemplarily, the sealing material 4 can be made of silica gel. Of course, the sealing material 4 can also be made of other water-tight materials.

[0077] In this way, the permeability testing method provided in the embodiment of the present application can prevent the testing liquid from leaking from the gap between the testing sample 3 and the inner wall surface of the testing tube 1 .

[0078] See also Figure 6 , the inner side of the test cylinder 1 is free from a support portion 13, and the support portion 13 can support the test sample 3. Exemplarily, the support portion 13 can extend at least half a circle around the axis of the test cylinder 1. For example, the support portion 13 can extend a circle around the axis of the test cylinder 1, that is, the support portion 13 can be annular. Exemplarily, there can be multiple support portions 13, and the multiple support portions 13 are arranged at intervals around the axis of the test cylinder 1.

[0079] S2, adding the test liquid into the test cylinder 1 so that the liquid level in the test cylinder 1 remains unchanged.

[0080] Exemplarily, the test liquid can be water. Of course, the test liquid can also be other liquid media. For example, the test liquid can be the liquid medium that the test sample 3 contacts when applied.

[0081] See also Figure 7 In some embodiments, in step S2, adding the test liquid into the test cylinder 1 so that the liquid level in the test cylinder 1 remains unchanged includes:

[0082] S21, adding a test liquid into the test tube 1;

[0083] S22, when the liquid level is higher than a preset height, drain the test liquid in the test cylinder 1 to make the liquid level in the test cylinder 1 reach the preset height.

[0084] Please continue reading Figure 2 and Figure 3It can be understood that a test device 100 used in the permeability test method provided in the embodiment of the present application includes a first liquid storage container 5 and a liquid inlet tube 51, and the liquid inlet tube 51 is respectively connected to the first liquid storage container 5 and the test cylinder 1. The first liquid storage container 5 can store the test liquid, and the test liquid in the first liquid storage container 5 can enter the test cylinder 1 through the liquid inlet tube 51.

[0085] In the permeability testing method provided in the embodiment of the present application, the first liquid storage container 5 can be used to add a test solution into the test cylinder 1. When the liquid level is higher than a preset height, the test liquid in the test cylinder 1 can be discharged, so that the liquid level in the test cylinder 1 is at the preset height.

[0086] In this way, the permeability testing method provided in the present application can maintain the liquid level in the test tube 1 at a preset height, so that the pressure of the test liquid of the test sample 3 remains unchanged during the permeability testing process.

[0087] See also Figure 8 In some other embodiments, in step S2, adding the test liquid into the test cylinder 1 so that the liquid level in the test cylinder 1 remains unchanged includes:

[0088] S21, continuously adding the test liquid into the test tube 1 through the liquid inlet 11;

[0089] S22, when the liquid level is higher than a preset height, drain the test liquid in the test cylinder 1 to make the liquid level in the test cylinder 1 reach the preset height.

[0090] In some examples, the liquid inlet 11 may be the upper opening of the test cylinder 1. The liquid inlet pipe 51 is connected to the upper opening of the test cylinder 1, and the test liquid in the first liquid storage container 5 may enter the test cylinder 1 through the upper opening of the test cylinder 1, without opening a hole in the side wall of the test cylinder 1.

[0091] In other examples, the liquid inlet 11 is disposed on the side wall of the test tube 1 , and the minimum distance between the side of the liquid inlet 11 and the test sample 3 is greater than or equal to a preset height.

[0092] In this way, the liquid inlet pipe 51 is connected to the liquid inlet 11, and the test liquid in the first liquid storage container 5 enters the test cylinder 1 through the liquid inlet 11. In addition, the minimum distance between the side of the liquid inlet 11 and the test sample 3 is greater than or equal to the preset height, which can prevent the test liquid from flowing out of the liquid inlet 11. In addition, when the test liquid is added to the test cylinder 1 through the liquid inlet 11, it can also avoid the formation of turbulence inside the test liquid in the test cylinder 1 to a certain extent, so as to avoid affecting the test results.

[0093] It can be understood that the first liquid storage container 5 is higher than the test cylinder 1 , and the test liquid in the first liquid storage container 5 can continue to flow into the test cylinder 1 under the action of gravity.

[0094] In addition, when the liquid level is higher than the preset height, the permeability test method provided by the present application can use the liquid outlet 12 to discharge the test liquid in the test tube 1. The liquid outlet 12 is arranged on the side wall of the test tube 1, and the minimum distance between the side of the liquid outlet 12 and the test sample 3 is equal to the preset height. When the liquid level is higher than the preset height, the test liquid in the test tube 1 flows out from the liquid outlet 12, and the liquid level will not be higher than the preset height. At the same time, the permeability test method provided by the embodiment of the present application also adds the test liquid into the test tube 1, and the liquid level will not be lower than the preset height, so that the liquid level is equal to the preset height.

[0095] In this way, the permeability testing method provided in the present application can continuously add test liquid to the test tube 1 to ensure that the liquid level is not lower than the preset height, and when the liquid level is higher than the preset height, the test liquid can be discharged from the liquid outlet 12, so that the preset height of the liquid level remains unchanged, which is conducive to improving the accuracy of the test results.

[0096] Please continue reading Figure 2 and Figure 3 It can be understood that a test device 100 used in the permeability test method provided in the embodiment of the present application also includes a second liquid storage container 6 and a liquid outlet pipe 61. The liquid outlet pipe 61 is connected to the second liquid storage container 6 and the test cylinder 1 respectively. The second liquid storage container 6 is lower than the test cylinder 1. The test liquid in the test cylinder 1 can enter the second liquid storage container 6 through the liquid outlet pipe 61. The second liquid storage container 6 can store the test liquid discharged from the test cylinder 1 to avoid the test liquid from being discharged at will.

[0097] A test device 100 used in the permeability test method provided in the embodiment of the present application further includes a liquid guide pump 7 and a liquid guide tube 71. The liquid guide pump 7 is arranged on the liquid guide tube 71. One end of the liquid guide tube 71 is connected to the first liquid storage container 5, and the other end of the liquid guide tube 71 is connected to the second liquid storage container 6. The permeability test method provided in the embodiment of the present application can use the liquid guide pump 7 and the liquid guide tube 71 to extract the test liquid in the second liquid storage container 6 into the first liquid storage container 5, so as to recycle the test liquid.

[0098] In addition, the upper end of the second liquid storage container 6 is open, and the liquid outlet pipe 61 extends into the second liquid storage container 6 through the upper end opening of the second liquid storage container 6, and the opening size of the upper end opening of the second liquid storage container 6 is larger than the size of the liquid outlet pipe 61, and the upper end opening of the second liquid storage container 6 is connected to the atmosphere. The test liquid in the test cylinder 1 enters the second liquid storage container 6 through the liquid outlet pipe 61, which can prevent the liquid guide pump 7 from directly sucking the test liquid in the test cylinder 1 through the liquid outlet pipe 61, and prevent the negative pressure generated by the liquid guide pump 7 from affecting the test liquid in the test cylinder 1.

[0099] The inventors have found that the test liquid entering the test cylinder 1 through the liquid inlet 11 has a certain flow rate and pressure, which will impact the test liquid in the test cylinder 1 and cause the test liquid in the test cylinder 1 to shake, thus affecting the test result.

[0100] Please also read Fig. 9 and Fig.10 In some other embodiments, in step S2, adding the test liquid into the test cylinder 1 so that the liquid level in the test cylinder 1 remains unchanged comprises:

[0101] S21, adding the test liquid into the test tube 1 by using the buffer chamber;

[0102] S22, when the liquid level is higher than a preset height, drain the test liquid in the test cylinder 1 to make the liquid level in the test cylinder 1 reach the preset height.

[0103] The buffer chamber is disposed in the test tube 1 and communicated with the liquid inlet 11 . The buffer chamber is provided with an overflow port, and the minimum distance between the side of the overflow port and the test sample 3 is greater than or equal to a preset height.

[0104] It can be understood that the overflow port can be located at the upper end of the cache chamber, and the overflow port can also be located on the side wall of the cache chamber.

[0105] In this way, the buffer chamber can buffer the test liquid added into the test cylinder 1 through the liquid inlet 11, so that the test liquid enters the test cylinder 1 through the overflow port, thereby preventing the test liquid entering the test cylinder 1 through the liquid inlet 11 from directly impacting the liquid surface in the test cylinder 1 and causing the liquid surface height to change, thereby avoiding affecting the test result.

[0106] Please also read Fig.11 and Fig.12 In some other embodiments, in step S2, adding the test liquid into the test cylinder 1 so that the liquid level in the test cylinder 1 remains unchanged comprises:

[0107] S21, adding a test liquid into the test cylinder 1, so that the liquid level in the test cylinder 1 reaches a preset height;

[0108] S22, when the liquid level is lower than the preset height, continue to add the test liquid into the test cylinder 1, so that the liquid level in the test cylinder 1 reaches the preset height.

[0109] Another testing device 100 used in the permeability testing method provided in the embodiment of the present application includes a third liquid storage container 8 and a connecting tube 9. The third liquid storage container 8 can store the test liquid, and the cross-sectional area of ​​the inner cavity of the third liquid storage container 8 is much larger than the cross-sectional area of ​​the inner cavity of the liquid storage cylinder.

[0110] It is understandable that the cross-sectional area of ​​the inner cavity of the third liquid storage container 8 can be 5 times or more than the cross-sectional area of ​​the inner cavity of the liquid storage cylinder. For example, the cross-sectional area of ​​the inner cavity of the third liquid storage container 8 is 5 times, 10 times, 20 times, 30 times, 40 times, 50 times, 60 times, etc., of the cross-sectional area of ​​the inner cavity of the liquid storage cylinder. In this way, when the liquid level in the test cylinder 1 changes within a certain range, the change in the liquid level in the third liquid storage container 8 can be ignored.

[0111] Optionally, the bottom wall surface of the inner cavity of the third liquid storage container 8 is flush with the top surface of the test sample 3 in the test cylinder 1, the third liquid storage container 8 has a first connecting port, the liquid storage cylinder has a second connecting port, and the connecting pipe 9 is connected to the first connecting port and the second connecting port respectively. The liquid level of the test liquid in the third liquid storage container 8 is equal to the above-mentioned preset height, the minimum distance between the side of the first connecting port and the test sample 3 is less than the preset height, and the minimum distance between the side of the second connecting port and the test sample 3 is less than the preset height.

[0112] Exemplarily, the maximum distance between the side of the first communication port and the test sample 3 is greater than the preset height, and the maximum distance between the side of the second communication port and the test sample 3 is greater than the preset height.

[0113] Exemplarily, the first communication port is at the same height as the second communication port.

[0114] When the test liquid in the test cylinder 1 permeates from the test sample 3, the liquid level of the test liquid in the test cylinder 1 drops, and the liquid level of the test liquid in the test cylinder 1 is lower than the preset height, and the test liquid in the third liquid storage container 8 flows into the test cylinder 1 through the connecting tube 9. The amount of the test liquid in the test cylinder 1 that permeates from the test sample 3 is small, and although it will cause the liquid level of the test liquid in the test cylinder 1 to change, the change in the liquid level of the test liquid in the third liquid storage container 8 is extremely small and can be ignored.

[0115] In this way, the permeability testing method provided in the embodiment of the present application can continue to add test liquid to the test tube 1 when the liquid level is lower than the preset height, so that the liquid level in the test tube 1 is maintained at the preset height, thereby making the pressure of the test liquid of the test sample 3 remain unchanged during the permeability test, which is beneficial to improving the accuracy of the test results.

[0116] S3, obtaining the volume flow rate of the test liquid seeping out of the test sample 3.

[0117] In some embodiments, after the liquid level in the test cylinder 1 reaches a preset height and a first preset time t1 has passed, a volume flow rate Qv of the test liquid seeping out of the test sample 3 is obtained.

[0118] It can be understood that after the first preset time t1, the amount of test liquid (seepage velocity) seeping out of the test sample 3 per unit time is stable, and the value of the volume flow Qv obtained is more accurate, which can improve the accuracy of the test result. Among them, the first preset time t1 can be obtained based on experience, or it can be the maximum time for the seepage of the test sample 3 to be stable in theory, and the first preset time t1 can be measured by a stopwatch.

[0119] In some embodiments, after the liquid level in the test cylinder 1 reaches a preset height and the seepage velocity of the test liquid in the test cylinder 1 stabilizes, the volume flow rate Qv of the test liquid seeping out of the test sample 3 is obtained.

[0120] It is understandable that whether the seepage rate is stable can be determined by observation. For example, the amount of test liquid seeping out is small, usually falling in the form of droplets, and whether the seepage rate is stable can be determined by counting the number of droplets within a certain period of time.

[0121] In this way, after the seepage velocity stabilizes, the value of the volume flow Qv obtained is more accurate, which can improve the accuracy of the test results.

[0122] In some embodiments, the testing device 100 used in the permeability testing method provided in the embodiments of the present application further includes a meter 2, which may include a measuring cup.

[0123] In step S3, obtaining the volume flow rate of the test liquid seeping out of the test sample 3 includes:

[0124] The volume V of the test liquid that seeps out within the second preset time t2 is measured, and the volume flow rate Qv is calculated according to the volume V and the second preset time t2.

[0125] It can be understood that the permeability testing method provided in the embodiment of the present application can allow the seeping test liquid to fall into a measuring cup, and measure the volume V of the test liquid that seeps out within the second preset time t2 through the measuring cup, and then calculate the volume flow rate Qv based on the volume V and the second preset time, wherein Qv=V / t2, and the second preset time t2 can be measured by a stopwatch.

[0126] Optionally, in the permeability testing method provided in the embodiment of the present application, when the seepage is stable, the measuring cup is read once, and after a second preset time t2, the measuring cup can be read again, and the difference between the two readings is the volume V.

[0127] Please continue reading Figure 2 , Figure 3 and Fig.11 In some embodiments, the test device 100 used in the permeability test method provided in the embodiment of the present application further includes a meter 2, which may include a weighing instrument 22 and a fourth liquid storage container 21, and the fourth liquid storage container 21 is placed on the weighing instrument 22. The weighing instrument 22 may be a balance.

[0128] In step S3, obtaining the volume flow rate of the test liquid seeping out of the test sample 3 includes:

[0129] The mass of the test liquid that seeps out within the second preset time t2 is measured, and the volume flow rate is calculated according to the mass and the second preset time.

[0130] It can be understood that the permeability test method provided in the embodiment of the present application can make the seeping test liquid fall into the fourth liquid storage container 21, and the mass m of the test liquid seeping out within the second preset time t2 can be measured by the weighing instrument 22, and the volume flow rate Qv is calculated according to the mass m and the second preset time t2, wherein Qv=m / (ρ*t2), the second preset time t2 can be measured by a stopwatch, and ρ is the density of the test liquid. Alternatively, Qm=m / t2, Qv=Qm / ρ, and Qm is the mass flow rate of the test liquid seeping out within the second preset time t2.

[0131] Optionally, in the permeability testing method provided in the embodiment of the present application, when the seepage is stable, a reading is taken on the weighing instrument 22, and after a second preset time t2, another reading may be taken on the weighing instrument 22, and the difference between the two readings is the mass m.

[0132] Optionally, in the permeability testing method provided in the embodiment of the present application, when the seepage is stable, the weighing instrument 22 is reset to zero, and after a second preset time t2, the mass m can be obtained by reading the weighing instrument 22.

[0133] S4, calculating the permeability of the test sample 3 according to the liquid level, the volume flow rate, the cross-sectional area of ​​the test sample 3 and the thickness of the test sample 3. The cross-sectional area of ​​the test sample 3 is perpendicular to the length direction of the test tube 1, and the thickness is the dimension of the test sample 3 along the length direction of the test tube 1.

[0134] Optionally, the permeability of the test sample 3 is K, and the calculation formula of K is:

[0135] K=-(u*μ*L) / △P. Wherein, u=Qv / S, △P=ρgh, Qv is the volume flow rate, S is the cross-sectional area of ​​the test sample 3, μ is the viscosity of the test liquid, L is the thickness of the test sample 3, ρ is the density of the test liquid, g is the acceleration of gravity, h is the liquid level, and △P is the pressure difference on both sides of the test sample 3. Wherein, the viscosity μ of the test liquid and the density ρ of the test liquid can be obtained according to the type of the test liquid, and the cross-sectional area S of the test sample 3 and the thickness L of the test sample 3 can be obtained by measuring the test sample 3.

[0136] Optionally, the permeability of the test sample 3 is calculated repeatedly for multiple times, and an average value of the multiple calculation results is taken as the permeability of the test sample 3.

[0137] In this way, the permeability testing method provided in the embodiment of the present application can calculate the permeability of the test sample 3 and make the calculation result more accurate.

[0138] Therefore, the permeability testing method provided by the present application can improve the accuracy of the test results and solve the technical problem of low accuracy of permeability testing in related technologies.

[0139] For example, the test liquid is water, t2 is 30s, m is 4.8850E-03Kg, Qm is 1.6283E-04Kg / s, and ρ is 1000Kg / m 3 , Qv is 1.6283E-07m 3 / s, S is 0.000176715m 2 , u is 9.2145E-04m / s, μ is 0.001pa.s, L is 0.002m, △P is 990.81pa, after calculation, K is 1.8600E-12m 2 .

[0140] For example, the test liquid is water, t2 is 30s, m is 5.0689E-03Kg, Qm is 1.6896E-04Kg / s, and ρ is 1000Kg / m 3 , Qv is 1.6896E-07m 3 / s, S is 0.000176715m 2 , u is 9.5613E-04m / s, μ is 0.001pa.s, L is 0.002m, △P is 990.81pa, and after calculation, K is 1.9300E-12m 2 .

[0141] For example, the test liquid is water, t2 is 30s, m is 4.9638E-03Kg, Qm is 1.6546E-04Kg / s, and ρ is 1000Kg / m 3, Qv is 1.6546E-07m 3 / s, S is 0.000176715m 2 , u is 9.3632E-04m / s, μ is 0.001pa.s, L is 0.002m, △P is 990.81pa, after calculation, K is 1.8900E-12m 2 .

[0142] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A permeability testing method, characterized in that: include: Placing the test sample in the test cylinder; Adding a test liquid into the test cylinder so that the liquid level in the test cylinder remains unchanged; obtaining a volume flow rate of a test liquid seeping out of the test sample; The permeability of the test sample is calculated according to the liquid level, the volume flow rate, the cross-sectional area of ​​the test sample and the thickness of the test sample, wherein the cross-sectional area of ​​the test sample is perpendicular to the length direction of the test cylinder, and the thickness is the dimension of the test sample along the length direction of the test cylinder.

2. The permeability testing method according to claim 1, characterized in that: The step of adding the test liquid into the test cylinder so that the liquid level in the test cylinder remains unchanged comprises: adding a test liquid into the test cylinder; When the liquid level is higher than a preset height, the test liquid in the test cylinder is discharged so that the liquid level in the test cylinder reaches the preset height.

3. The permeability testing method according to claim 2, characterized in that: When the liquid level is higher than the preset height, the test liquid in the test cylinder is discharged using a liquid outlet, wherein the liquid outlet is arranged on a side wall of the test cylinder, and a minimum distance between a side of the liquid outlet and the test sample is equal to the preset height.

4. The permeability testing method according to claim 2, characterized in that: Adding the test liquid into the test cylinder comprises: The test liquid is continuously added into the test cylinder via the liquid inlet.

5. The permeability testing method according to claim 4, characterized in that: The liquid inlet is disposed on a side wall of the testing cylinder, and a minimum distance between a side edge of the liquid inlet and the testing sample is greater than or equal to the preset height.

6. The permeability testing method according to claim 4, characterized in that: The adding the test liquid into the test cylinder further comprises: A test liquid is added to the test cylinder using a buffer chamber, wherein the buffer chamber is disposed in the test cylinder and is connected to the liquid inlet, the buffer chamber is provided with an overflow port, and the minimum distance between the side of the overflow port and the test sample is greater than or equal to the preset height.

7. The permeability testing method according to claim 2, characterized in that: After the liquid level in the test cylinder reaches the preset height and a first preset time has passed, a volume flow rate of the test liquid seeping out of the test sample is obtained; Alternatively, after the liquid level in the test cylinder reaches the preset height and the seepage velocity of the test liquid in the test cylinder is stabilized, the volume flow rate of the test liquid seeping out of the test sample is obtained.

8. The permeability testing method according to any one of claims 1 to 7, characterized in that: The step of adding the test liquid into the test cylinder so that the liquid level in the test cylinder remains unchanged comprises: Adding a test liquid into the test cylinder so that the liquid level in the test cylinder reaches a preset height; When the liquid level is lower than the preset height, continue to add the test liquid into the test cylinder so that the liquid level in the test cylinder reaches the preset height; and / or, Placing the test sample in the test cylinder comprises: A water-tight sealing material is provided at least on the peripheral surface of the test sample; The test sample is placed in the test cylinder so that the sealing material abuts against the inner wall surface of the test cylinder.

9. The permeability testing method according to any one of claims 1 to 7, characterized in that: The step of obtaining the volume flow rate of the test liquid seeping out of the test sample comprises: measuring the volume of the test liquid that seeps out within a second preset time, and calculating the volume flow rate according to the volume and the second preset time; Alternatively, the mass of the test liquid that seeps out within a second preset time is measured, and the volume flow rate is calculated based on the mass and the second preset time.

10. The permeability testing method according to any one of claims 1 to 7, characterized in that: Both ends of the testing tube in the length direction are open; and / or, repeatedly calculating the permeability of the test sample for multiple times, and taking the average value of the multiple calculation results as the permeability of the test sample; And / or, the permeability of the test sample is K, and the calculation formula of K is: K = -(u*μ*L) / △P, wherein u = Qv / S, △P = ρgh, Qv is the volume flow rate, S is the cross-sectional area of ​​the test sample, μ is the viscosity of the test liquid, L is the thickness of the test sample, ρ is the density of the test liquid, g is the acceleration of gravity, and h is the liquid level.

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