A device for measuring the permeability of thin-layer porous fiber materials

Abstract

The present invention relates to the technical field of fiber material detection, and discloses a device for measuring the permeability of a thin layer of porous fiber material, comprising a supply assembly, a supply pipe, a flow control assembly and a sample storage assembly; the sample storage assembly comprises a base, an inlet pipe, an outlet pipe, a pressure sensor and a top cover; a sample storage tank is provided on the base, and the top cover is used to cover the base to seal the sample storage tank; one end of the inlet pipe is connected to one end of the supply pipe, and the other end thereof passes through the top cover and is connected to one end of the sample storage tank; one end of the outlet pipe is connected to the other end of the sample storage tank, and the other end thereof passes through the top cover; pressure sensors are provided at both the inlet pipe and the outlet pipe; the other end of the supply pipe is connected to the supply assembly, and the flow control assembly is used to control the flow of the supply pipe. The device for measuring the permeability of a thin layer of porous fiber material proposed by the present invention has a simple structure and is easy to operate, and can provide a standardized instrument for measuring the permeability of a thin layer of porous fiber material, so that the measurement result is accurate and reliable.

Description

Technical Field

[0001] The invention relates to the technical field of fiber material detection, in particular to a device for measuring the permeability of a thin-layer porous fiber material. Background Art

[0002] Thin-layer fibrous porous materials are commonly found in today's daily necessities, such as sanitary products, fuel cells, textiles, etc. A major feature of thin-layer fibrous materials is that their thickness is much smaller than their length, which may lead to anisotropy of the hydraulic properties of thin-layer fibers. In addition, the different directions of the fiber filaments in the thin layer will also affect its hydraulic properties. Therefore, experimentally measuring the hydraulic properties of thin-layer fibrous porous materials is very important for a comprehensive understanding and simulation of fluid flow and solute transport in thin-layer fibrous porous materials.

[0003] Most of the existing methods for measuring the hydraulic properties of thin-layer fibrous porous materials are still at the numerical simulation stage. In particular, the evaluation of the basic hydraulic parameter permeability of thin-layer fibrous porous materials is still at the stage of numerical estimation based on the fiber radius. The obtained value has a certain deviation from the true value and is not very accurate. Summary of the invention

[0004] The purpose of the present invention is: the present invention provides a device for measuring the permeability of thin-layer porous fiber materials to solve the technical problem that the evaluation of the permeability of thin-layer fibrous porous materials in the prior art still remains in the numerical estimation stage, the obtained numerical value has a certain deviation from the true value, and the accuracy is not high.

[0005] In order to achieve the above-mentioned object, the present invention provides a device for measuring the permeability of a thin layer of porous fiber material, comprising a supply component, a supply pipe, a flow control component and a sample storage component;

[0006] The sample storage assembly comprises a base, an inlet pipe, an outlet pipe, a pressure sensor and a top cover;

[0007] The base is provided with a sample storage tank, and the top cover is used to cover the base to seal the sample storage tank;

[0008] One end of the inlet pipe is connected to one end of the supply pipe, and the other end thereof passes through the top cover and is connected to one end of the sample storage tank;

[0009] One end of the outlet pipe is connected to the other end of the sample storage tank, and the other end thereof passes through the top cover;

[0010] The pressure sensor is provided at both the inlet pipe and the outlet pipe;

[0011] The other end of the supply pipe is communicated with the supply assembly, and the flow control assembly is used to control the flow of the supply pipe.

[0012] In some embodiments of the present application, triangular buffer grooves are respectively provided at both ends of the sample storage tank, and the inlet pipe and the outlet pipe are both connected to the ends of the triangular buffer grooves.

[0013] In some embodiments of the present application, the bottom of the top cover and the surface of the sample storage tank are coated with a vacuum grease layer.

[0014] In some embodiments of the present application, a sealing ring is provided around the edge of the sample storage tank.

[0015] In some embodiments of the present application, the supply assembly includes a liquid supply bottle, a liquid outlet pipe, a gas supply bottle, a gas outlet pipe and a three-way valve;

[0016] One end of the liquid outlet pipe is connected to the liquid supply bottle, and the other end thereof is connected to the three-way valve;

[0017] One end of the gas outlet pipe is connected to the gas supply bottle, and the other end is connected to the three-way valve;

[0018] The supply pipe is connected to the three-way valve.

[0019] In some embodiments of the present application, the flow control assembly includes a flow controller and a control valve;

[0020] The flow controller is arranged at one end of the supply tube away from the sample storage assembly, and is used to control the flow rate of the supply tube;

[0021] The control valve is arranged at one end of the supply pipe close to the sample storage assembly, and is used to control the opening or closing of the supply pipe.

[0022] In some embodiments of the present application, a flow meter is further included; the flow meter is arranged at the outlet pipe end.

[0023] In some embodiments of the present application, the sample storage tank is a rectangular tank, and its depth is the same as the thickness of the sample to be tested.

[0024] In some embodiments of the present application, the top cover and the base are locked together by screws.

[0025] In some embodiments of the present application, the top cover is made of a transparent acrylic plate.

[0026] Compared with the prior art, the device for measuring the permeability of a thin layer of porous fiber material according to the embodiment of the present invention has the following beneficial effects:

[0027] The device for measuring the permeability of a thin layer porous fiber material provided by the present invention has a simple structure and is easy to operate, and can provide a standardized instrument for measuring the permeability of a thin layer porous fiber material, so that the measurement result is accurate and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, 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 invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0029] Figure 1 It is a schematic structural diagram of a device for measuring the permeability of a thin layer of porous fiber material according to an embodiment of the present invention;

[0030] Figure 2 is a schematic diagram of the top view of the sample storage assembly with the top cover removed;

[0031] Figure 3 It is a front view structural schematic diagram of the sample storage component;

[0032] Figure 4 is the SEM image of the upper surface of the sample TY1 to be tested;

[0033] Figure 5 is the SEM image of the lower surface of the sample TY1 to be tested;

[0034] Figure 6 is the SEM image of the upper surface of the sample TY2 to be tested;

[0035] Figure 7 is the SEM image of the lower surface of the sample TY2 to be tested;

[0036] In the figure, 1. supply assembly; 11. liquid supply bottle; 12. liquid outlet pipe; 13. gas supply bottle; 14. gas outlet pipe; 15. three-way valve; 2. supply pipe; 3. flow control assembly; 31. flow controller; 32. control valve; 4. sample storage assembly; 41. top cover; 42. base; 43. inlet pipe; 44. outlet pipe; 45. pressure sensor; 5. sample storage tank; 51. triangular buffer tank; 6. sealing ring; 7. flow meter; 8. screw. DETAILED DESCRIPTION

[0037] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0038] In the description of the present invention, it is necessary to understand that the orientations or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “top” and “bottom” are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They 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 cannot be understood as a limitation on the present invention.

[0039] It should be understood that the orientation or position relationship indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention 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 operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0040] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0041] See also Figure 1 -3 is a device for measuring the permeability of a thin layer of porous fiber material according to a preferred embodiment of the present invention, comprising a supply component 1, a supply pipe 2, a flow control component 3 and a sample storage component 4.

[0042] See also Figure 2 and Figure 3 The sample storage assembly 4 includes a base 42, an inlet pipe 43, an outlet pipe 44, a pressure sensor 45 and a top cover 41. A sample storage tank 5 is provided on the base 42, and the top cover 41 is used to cover the base 42 to seal the sample storage tank 5. One end of the inlet pipe 43 is connected to one end of the supply pipe 2, and the other end thereof passes through the top cover 41 and is connected to one end of the sample storage tank 5. One end of the outlet pipe 44 is connected to the other end of the sample storage tank 5, and the other end thereof passes through the top cover 41. Pressure sensors are provided at both the inlet pipe and the outlet pipe. The other end of the supply pipe 2 is connected to the supply assembly 1, and the flow control assembly 3 is used to control the flow of the supply pipe 2.

[0043] In some embodiments of the present application, see Figure 1 The supply assembly 1 includes a liquid supply bottle 11, a liquid outlet pipe 12, a gas supply bottle 13, a gas outlet pipe 14 and a three-way valve 15. One end of the liquid outlet pipe 12 is connected to the liquid supply bottle 11, and the other end thereof is connected to the three-way valve 15. One end of the gas outlet pipe 14 is connected to the gas supply bottle 13, and the other end thereof is connected to the three-way valve 15. The supply pipe 2 is connected to the three-way valve 15, and the supply pipe 2 is switched to discharge liquid or discharge gas through the three-way valve 15 to meet different measurement requirements.

[0044] In some embodiments of the present application, see Figure 2 A triangular buffer groove 51 is respectively disposed at both ends of the sample storage tank 5 , and the inlet pipe 43 and the outlet pipe 44 are both connected to the ends of the triangular buffer groove 51 .

[0045] In some embodiments of the present application, see Figure 2 The sample storage tank 5 is a rectangular tank, and its depth is the same as the thickness of the sample to be tested.

[0046] In some embodiments of the present application, the bottom of the top cover 41 and the surface of the sample storage tank 5 are coated with a thin layer of vacuum grease, which can fill the gap between the sample to be tested and the sample storage tank 5 to prevent the wall preferential flow from affecting the measurement results, which is beneficial to improving the accuracy of the measurement results.

[0047] In some embodiments of the present application, see Figure 2 A sealing ring 6 is provided around the edge of the sample storage tank 5 to help ensure the sealing between the top cover 41 and the base 42.

[0048] In some embodiments of the present application, see Figure 1 The flow control assembly 3 includes a flow controller 31 and a control valve 32. The flow controller 31 is arranged at one end of the supply pipe 2 away from the sample storage assembly 4, and is used to control the flow rate of the supply pipe 2. The control valve 32 is arranged at one end of the supply pipe 2 close to the sample storage assembly 4, and is used to control the opening or closing of the supply pipe 2.

[0049] In some embodiments of the present application, see Figure 1 , and also includes a flow meter 7, which is arranged at the end of the outlet pipe 44 and is used to detect and display the liquid or gas output of the outlet pipe 44 in real time, and compare it with the flow controller reading of the flow controller 31 to check whether the device is leaking.

[0050] In some embodiments of the present application, see Figure 2 The top cover 41 and the base 42 are locked together by screws 8 to ensure sealing reliability.

[0051] In some embodiments of the present application, the top cover 41 is made of a transparent acrylic plate to facilitate observation of the measurement process.

[0052] The device for measuring the permeability of a thin layer porous fiber material of the present invention can be used to measure the gas phase permeability or water phase permeability of a thin layer porous fiber material sample to be tested.

[0053] When it is necessary to measure the gas permeability of a thin layer of porous fiber material sample, the steps are as follows:

[0054] The first step is to use a 3D printer to customize and print a plastic base 42 with a sample storage tank 5 of corresponding thickness according to the thickness of the thin layer porous fiber material sample to be tested.

[0055] Step 2: Place the dry sample to be tested into the sample storage tank 5 , and seal and fix the top cover 41 and the base 42 with screws 8 .

[0056] Step 3: Rotate the three-way valve 15 to switch the supply pipe 2 to the gas outlet state, and open the control valve 32 to pass gas into the sample storage tank 5. In this process, the gas flow rate can be adjusted by the flow controller 31 and compared with the reading of the flow meter 7 at the outlet pipe 44 to ensure that the device is sealed and leak-proof.

[0057] Step 4: After the gas is introduced and stabilized, the readings of the pressure sensors 45 at the inlet pipe 43 and the outlet pipe 44 are automatically recorded.

[0058] Step 5: According to Darcy's law formula:

[0059]

[0060] Where q is the flow velocity in m / s; k is the absolute permeability in m 2 ; p is pressure, unit is Pa; x is length, unit is m; μ is viscosity coefficient, unit is Pa s;

[0061] In formula (1), the flow rate q can be obtained from the reading of the flow controller 31, Δp is the reading difference of the inlet and outlet pressure sensors 45, and Δx is the length of the sample to be measured. In this embodiment, Δx is 20 cm. Therefore, the absolute permeability k can be obtained according to formula (1), and multiple groups of measurement data can be obtained by repeating multiple groups of measurements.

[0062] When it is necessary to measure the liquid permeability of a thin layer of porous fiber material sample, the steps are as follows:

[0063] The first step is to use a 3D printer to customize and print a plastic base 42 with a sample storage tank 5 of corresponding thickness according to the thickness of the thin layer porous fiber material sample to be tested. Taking pure water as an example, the liquid supply bottle 11 is filled with pure water.

[0064] The second step is to apply a thin layer of vacuum grease on the bottom of the top cover 41 and the surface of the sample storage tank 5.

[0065] Step 3: Place the sample to be tested that is pre-saturated with water into the sample storage tank 5 , and ensure that the entire device, especially the sample storage tank 5 , is filled with pure water, and seal and fix the top cover 41 and the base 42 with screws 8 .

[0066] Step 4: Rotate the three-way valve 15 to switch the supply pipe 2 to the water outlet state, and open the control valve 32 to pass pure water into the sample storage tank 5. In this process, the pure water flow rate can be adjusted by the flow controller 31 and compared with the reading of the flow meter 7 at the outlet pipe 44 to ensure that the device is sealed and leak-proof.

[0067] Step 5: After the gas is introduced and stabilized, the readings of the pressure sensors 45 at the inlet pipe 43 and the outlet pipe 44 are automatically recorded.

[0068] Step 6: Calculate the absolute permeability k according to Darcy's law formula (the calculation process is shown in the fifth step of measuring gas phase permeability).

[0069] Example 1

[0070] In this embodiment, two thin-layer fiber materials are tested. The two thin-layer fiber materials are coded as TY1 and TY2 respectively. Their relevant parameters are shown in Table 1, and their scanning electron microscope images are shown in Figure 4 - Figure 7 .

[0071] Furthermore, in order to study whether the thin layer fiber material is uniform in all directions, this embodiment measures cross-section (0°), vertical section (90°) and oblique section (45°) samples with a width of 1 cm of two thin layer fiber materials, that is, a total of six groups of test samples are measured, and the test sample numbers are 0TY1, 90TY1, 45TY1, 0TY2, 90TY2, and 45TY2 respectively.

[0072] nature TY1 TY2 Thickness(mm) 0.7 0.69 Porosity, φ(-) 0.91 0.87

[0073] Table 1

[0074] First, pure water and CO 2 The vacant permeability of the device (without sample) was measured, and the results showed that the controlled permeability of the device was much greater than the sample permeability and could be ignored.

[0075] Then, according to the above-mentioned gas permeability and liquid permeability measurement steps of the thin layer porous fiber material to be tested, the gas permeability and liquid permeability of the six groups of samples were measured, and each group of tests was performed 3 times. The absolute permeability k results obtained are shown in Table 2 below.

[0076]

[0077]

[0078] Table 2

[0079] In summary, the present invention proposes a device for measuring the permeability of a thin layer of porous fiber materials, which has a simple structure and is easy to operate. It can provide a standardized instrument for measuring the permeability of a thin layer of porous fiber materials, making the measurement results accurate and reliable.

[0080] Moreover, the same set of devices can be used to measure the gas permeability or liquid permeability of a thin layer of porous fiber material to be tested through simple adjustments, and has strong applicability and high flexibility.

[0081] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A device for measuring the permeability of a thin layer of porous fiber material, characterized in that: It includes a supply component, a supply pipe, a flow control component and a sample storage component; The sample storage assembly comprises a base, an inlet pipe, an outlet pipe, a pressure sensor and a top cover; The base is provided with a sample storage tank, and the top cover is used to cover the base to seal the sample storage tank; One end of the inlet pipe is connected to one end of the supply pipe, and the other end thereof passes through the top cover and is connected to one end of the sample storage tank; One end of the outlet pipe is connected to the other end of the sample storage tank, and the other end thereof passes through the top cover; The pressure sensor is provided at both the inlet pipe and the outlet pipe; The other end of the supply pipe is in communication with the supply assembly, and the flow control assembly is used to control the flow of the supply pipe; The two ends of the sample storage tank are respectively provided with triangular buffer tanks, and the inlet pipe and the outlet pipe are both connected to the ends of the triangular buffer tanks; The bottom of the top cover and the surface of the sample storage tank are coated with a vacuum grease layer; The supply assembly comprises a liquid supply bottle, a liquid outlet pipe, a gas supply bottle, a gas outlet pipe and a three-way valve; One end of the liquid outlet pipe is connected to the liquid supply bottle, and the other end thereof is connected to the three-way valve; One end of the gas outlet pipe is connected to the gas supply bottle, and the other end is connected to the three-way valve; The supply pipe is connected to the three-way valve.

2. The device for measuring the permeability of a thin layer of porous fiber material according to claim 1, characterized in that: A sealing ring is arranged around the edge of the sample storage tank.

3. The device for measuring the permeability of a thin layer of porous fiber material according to claim 1, characterized in that: The flow control assembly includes a flow controller and a control valve; The flow controller is arranged at one end of the supply tube away from the sample storage assembly, and is used to control the flow rate of the supply tube; The control valve is arranged at one end of the supply pipe close to the sample storage assembly, and is used to control the opening or closing of the supply pipe.

4. The device for measuring the permeability of a thin layer of porous fiber material according to claim 3, characterized in that: It also includes a flow meter; the flow meter is arranged at the outlet pipe end.

5. The device for measuring the permeability of a thin layer of porous fiber material according to claim 1, characterized in that: The sample storage tank is a rectangular tank, and its depth is the same as the thickness of the sample to be tested.

6. The device for measuring the permeability of a thin layer of porous fiber material according to claim 1, characterized in that: The top cover and the base are locked together by screws.

7. The device for measuring the permeability of a thin layer of porous fiber material according to claim 1, characterized in that: The top cover is made of a transparent acrylic plate.

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