CN113324468B - Testing device and testing method for measuring seepage height of reverse seepage experiment - Google Patents

Testing device and testing method for measuring seepage height of reverse seepage experiment Download PDF

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CN113324468B
CN113324468B CN202110718982.8A CN202110718982A CN113324468B CN 113324468 B CN113324468 B CN 113324468B CN 202110718982 A CN202110718982 A CN 202110718982A CN 113324468 B CN113324468 B CN 113324468B
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resistance wire
glass tube
resistance
power supply
height
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CN113324468A (en
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刘震
董博文
杨赫
赵大伟
朱慕尧
张凯萌
程卫民
周刚
王刚
林小路
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Shandong University of Science and Technology
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
    • G01B7/02—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring length, width or thickness
    • G01B7/06—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring length, width or thickness for measuring thickness
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N13/00—Investigating surface or boundary effects, e.g. wetting power; Investigating diffusion effects; Analysing materials by determining surface, boundary, or diffusion effects
    • G01N13/04—Investigating osmotic effects
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N13/00—Investigating surface or boundary effects, e.g. wetting power; Investigating diffusion effects; Analysing materials by determining surface, boundary, or diffusion effects
    • G01N2013/003—Diffusion; diffusivity between liquids

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Abstract

The invention has proposed a measuring device and test method for measuring the experiment infiltration height of reverse infiltration suction, the measuring device includes there are glass tubes with both ends open on the iron stand, there are two non-intersecting resistance wires without insulating wrapping in the glass tube, one end of the first resistance wire couples to first end of test input of the display instrument through the first wire, one end of the second resistance wire couples to second end of test input of the display instrument through the second wire, the data terminal of the display instrument couples to computer; the bottom of the glass tube is wrapped by filter paper and fixed by a rubber band; the glass tube is filled with an object to be detected, the water container is placed at the bottom of the glass tube, and the water container is filled with a conducting liquid capable of conducting the first resistance lead and the second resistance lead; the device also comprises a liquid level titration device, and the liquid level of the conducting liquid in the water containing vessel can be flush with the bottom of the glass tube through the liquid level titration device. The invention has simple steps, quick installation, convenient use and easy mastering; the measurement of the imbibition height is realized.

Description

Testing device and testing method for measuring seepage height of reverse seepage experiment
Technical Field
The invention relates to the technical field of testing devices, in particular to a testing device and a testing method for measuring the imbibition height of a reverse imbibition experiment.
Background
Mine dust is a dangerous factor threatening the safety production of coal mines, and the coal seam water injection technology can enable high-pressure water to enter a coal body cracking-pore structure, increase the water content of the coal body and fundamentally inhibit the generation of dust, so that the coal seam water injection technology becomes one of the most basic and most effective dust reduction technical means of the coal mine fully mechanized mining working face in China. The coal seam water injection process comprises three stages of hydraulic fracturing, water seepage and capillary wetting, wherein the capillary wetting refers to a process that water flows into each pore structure of coal body through a capillary phenomenon to fully contact with the surface of the coal and wet the coal body, so that the research on the wetting characteristic of the coal body is very important for the development of the field coal seam water injection dust reduction technology, and a spontaneous seepage experiment is a common experimental means for measuring the wetting characteristic of solid particles. In the reverse spontaneous imbibition experiment, the formed coal powder column is a porous medium, a large number of pore channels exist inside the coal powder column, the radius of the pore channels is different, the difference of the imbibition height of each channel is large, and the phenomenon is macroscopically that the accurate numerical value of the imbibition height is difficult to read. Therefore, an experimental test device for measuring the imbibition height by an indirect method is needed, and a feasible and reliable experimental equipment foundation is laid for researching the wetting characteristic of the coal particles.
Disclosure of Invention
The invention aims to at least solve the technical problems in the prior art, and particularly creatively provides a testing device and a testing method for measuring the imbibition height of a reverse imbibition experiment.
In order to achieve the purpose, the invention provides a testing device for measuring the infiltration height of a reverse infiltration experiment, which comprises an iron support, wherein a glass tube with openings at two ends is arranged on the iron support, two non-intersecting resistance wires without insulation wrapping are arranged in the glass tube, namely a resistance wire I and a resistance wire II, one end of the resistance wire I is connected with a first test input end of a display instrument through the wire I, one end of the resistance wire II is connected with a second test input end of the display instrument through the wire II, and a data end of the display instrument is connected with a computer;
the bottom of the glass tube is wrapped by filter paper and fixed by a rubber band; the glass tube is filled with an object to be detected, the water container is placed at the bottom of the glass tube, and the water container is filled with a conducting liquid capable of conducting the first resistance lead and the second resistance lead;
the device also comprises a liquid level titration device, and the liquid level of the conducting liquid in the water containing vessel can be flush with the bottom of the glass tube through the liquid level titration device.
In a preferred embodiment of the invention, the liquid level titration device comprises a burette arranged at the upper end of a water container and a titration system for controlling titration of the burette, the titration system comprises a buoy arranged in the water container, one end of a constraint line is arranged at the central position of the bottom of the buoy, the other end of the constraint line is arranged at the inner bottom of the water container, and a communicating body is arranged at the top of the buoy;
the upper end of the water containing vessel is also provided with a first electrode and a second electrode, the first electrode is connected with the input first end of the control module through a first connecting wire, and the second electrode is connected with the input second end of the control module through a second connecting wire;
when the liquid level in the water container makes the buoy support the communicating body and simultaneously contact with the first electrode and the second electrode, the control module controls the burette to stop titrating the conducting liquid into the water container;
when the communicating body of the titration tube is not simultaneously contacted with the first electrode and the second electrode, the control module controls the titration tube to titrate the conducting liquid into the water containing vessel; until the communicating body is contacted with the first electrode and the second electrode at the same time.
In a preferred embodiment of the invention, the control module comprises a solenoid valve for controlling the titration of the conducting liquid into the water containing vessel and a flow metering valve for metering the volume of the titration conducting liquid into the water containing vessel arranged at the titration part of the burette or/and a graduation line for reading the volume of the titration conducting liquid into the water containing vessel arranged on the burette tube body, the first end of a relay input loop is connected with a 3.3V power supply, the second end of the relay input loop is connected with a collector electrode of a triode, an emitter electrode of the triode is connected with the first end of a current-limiting resistor, the second end of the current-limiting resistor is connected with a power ground, a base electrode of the triode is connected with the titration control end of the titration controller, the detection input end of the titration controller is respectively connected with the first end of a connecting wire I and the first end of a voltage-dividing resistor, the second end of the voltage-dividing resistor is connected with the power ground, the second end of the connecting wire is connected with the first end of a voltage-dividing resistor, the second end of the first divider resistor is connected with a 3.3V power supply, a normally open contact of the relay is connected in series in a power supply loop of the electromagnetic valve, a flow data output end of the flow metering valve is connected with a flow data input end of the titration controller, and a flow data end of the titration controller is connected with a computer. When the communicating body of the titration controller is simultaneously contacted with the first electrode and the second electrode, the titration controller detects that the voltage input into the titration controller is about 3.0V of power supply voltage, the 3.0V of power supply voltage is considered to be high level, at the moment, the titration controller sends cut-off level to the base electrode of the triode of the titration controller, the triode is in a cut-off state, and the relay is in a normally open state; the power supply loop of the normally closed solenoid valve is not conducted to be electrified, the normally closed solenoid valve is in a closed state, and the burette does not titrate the conducting liquid into the water container. When the communicating body of the titration controller is not simultaneously contacted with the first electrode and the second electrode, the titration controller detects that the voltage input into the titration controller is 0V power supply voltage, the voltage is considered to be low level at the moment, the titration controller sends a conducting level to the base electrode of a triode of the titration controller at the moment, the triode is in a conducting state, and the relay is changed from a normally open state to a closed state; the power supply circuit of the normally closed electromagnetic valve is conducted to be electrified, the normally closed electromagnetic valve is in an open state, and the burette titrates the conducting liquid into the water containing vessel.
In a preferred embodiment of the present invention, the iron support includes a base, a vertical lifting rod is disposed on the base, and a horizontal lifting clamp capable of adjusting height up and down is disposed on the vertical lifting rod; the glass tube is vertically clamped on the horizontal lifting clamp, and the water containing vessel is arranged on the base.
In a preferred embodiment of the present invention, the display instrument includes a housing and a display screen disposed on a surface of the housing, a PCB fixing seat for fixing and mounting a PCB is disposed in the housing, the PCB is fixedly mounted on the PCB fixing seat, a voltage detecting unit for detecting a voltage value between the resistance wires and a current detecting unit for detecting a current value between the resistance wires are disposed on the PCB, and a controller, a data transmitting unit and a power voltage adjusting unit are disposed on the PCB;
the power supply output first end of the power supply voltage regulating unit is connected with the first end of the current limiting resistor, the second end of the current limiting resistor is connected with the test input first end of the display instrument, the power supply output second end of the power supply voltage regulating unit is connected with the test input second end of the display instrument, the voltage regulating end of the power supply voltage regulating unit is connected with the voltage regulating end of the controller, and the controller sends a voltage regulating signal to the power supply voltage regulating unit to change the power supply voltage output by the power supply voltage regulating unit;
a detection loop of the voltage detection unit is connected with the resistance wire in parallel, namely, a voltage detection first end of the voltage detection unit is connected with a test input first end of the display instrument, a voltage detection second end of the voltage detection unit is connected with a test input second end of the display instrument, and a voltage data output end of the voltage detection unit is connected with a voltage data input end of the controller; the detection circuit of the current detection unit is connected in series in the resistance wire circuit, the current data output end of the current detection unit is connected with the current data input end of the controller, the data transmission end of the controller is connected with the data transmission end of the data transmission unit, and the data display end of the controller is connected with the data display end of the display screen;
the method for calculating the imbibition height of the imbibition height comprises the following steps:
in the first step, the controller controls the power supply voltage adjusting unitOutputting a supply voltage U during a detection period1～UTWherein U isjIs less than Uj+1A positive number of (d); j is 1, 2, 3, … …, T-1; t is a positive integer greater than or equal to 2;
the second step, the output power voltage of the power supply voltage regulating unit is UiWhen i is 1, 2, 3, … …, T; and calculating the resistance value of the resistance wire:
Figure GDA0003597595680000041
wherein T represents the number of different power supply voltages output by the power supply voltage regulating unit;
Figure GDA0003597595680000042
representing a resistance value measured in the measurement loop;
Figure GDA0003597595680000043
wherein R is0The resistance value of the first resistance wire and the second resistance wire is represented;
r represents the resistance value of the resistance wire in the loop;
R0＝(1-φ)ηl，
where φ represents an error coefficient, φ ∈ (0,0.115 ];
eta represents the conduction rate of the conduction liquid between the first resistance lead and the second resistance lead;
l represents the distance between the first resistance wire and the second resistance wire;
Figure GDA0003597595680000044
wherein ε represents the resistivity of the resistive wire;
l represents the length of the resistance wire in the glass tube, L ═ L1+L2，L1Indicates the length of the first resistor conductor, L2The length of the second resistance lead is shown;
h represents the imbibition height displayed by the display instrument
S represents the cross-sectional area of the resistance wire;
thirdly, solving the imbibition height:
Figure GDA0003597595680000051
the invention also discloses a testing method of the testing device for measuring the imbibition height of the reverse imbibition experiment, which comprises the following steps:
s1, fixing the first resistance wire without insulation coating on the inner wall of the glass tube, placing the second resistance wire without insulation coating in the center of the glass tube, keeping one end of the first resistance wire and one end of the second resistance wire level with the bottom of the glass tube, and leading the other ends of the first resistance wire and the second resistance wire out of the glass tube after being respectively connected with the first resistance wire and the second resistance wire;
s2, fixing filter paper at the bottom of a glass tube through a rubber band, pouring coal powder from the upper end of the glass tube, vibrating the glass tube to enable the coal powder to form a coal powder column with uniform density, and vertically clamping the glass tube by using a transverse lifting clamp;
s3, injecting a certain amount of conducting liquid into the water containing vessel, horizontally placing the conducting liquid on the base, placing the buoy with the top provided with the small iron block on the liquid level, adjusting the position of the lifting frame to enable the electrode I and the electrode II to be just contacted with the small iron block, connecting the buoy switch with the control module through the connecting wire I and the connecting wire II, and adjusting the position of the liquid injection port of the burette to be slightly higher than the liquid level;
s4, connecting the first resistance lead and the second resistance lead at the upper end of the glass tube with a display instrument, and adjusting the height of the glass tube to enable the bottom end of the glass tube to be level with the liquid level;
when the liquid level rises to the original height again, the first electrode and the second electrode contact with the iron block, and the burette stops injecting liquid;
meanwhile, the imbibition height is changed, the imbibition height is displayed in a digital mode through a display instrument, and the computer records the imbibition height in real time;
and S5, mutually verifying the calculated imbibition height through the burette and the imbibition height calculated by the display instrument to obtain more accurate imbibition height.
In a preferred embodiment of the present invention, in step S5, the calculation method of the imbibition height calculated by the burette includes:
Figure GDA0003597595680000061
in the formula: vGeneral assembly-total volume of titration;
Vsteaming food-total volume of evaporation;
r-glass tube radius;
rho-the void ratio of coal powder accumulation;
h-imbibition height;
in step S5, the calculation method of the calculated suction height of the display meter is:
Figure GDA0003597595680000062
wherein L represents the length of the resistance wire in the glass tube, and L is L1+L2，L1Indicates the length of the first resistance wire, L2The length of the second resistance lead is shown;
s represents the cross-sectional area of the resistance wire;
ε represents the resistivity of the resistive wire;
t represents the number of different power supply voltages output by the power supply voltage regulating unit;
Figure GDA0003597595680000071
indicating that the output power supply voltage of the power supply voltage regulating unit is UiThen, the voltage value detected by the voltage detection unit;
Figure GDA0003597595680000072
indicating that the output power supply voltage of the power supply voltage regulating unit is UiThe current value detected by the current detection unit;
phi denotes an error coefficient, phi ∈ (0,0.115 ];
eta represents the conduction rate of the conduction liquid between the first resistance lead and the second resistance lead;
l represents the distance between the first resistance wire and the second resistance wire;
h represents the imbibition height indicated by the display meter.
In a preferred embodiment of the present invention, in step S5, if | H-H | < ═ H0Wherein H represents the imbibition height displayed by a display instrument, H-imbibition height; | | represents taking an absolute value; -means less than or equal to; h0Representing a threshold value of the difference of imbibition heights; then
Figure GDA0003597595680000073
h0Indicating the exact imbibition height;
if | H-H | > H0And H > H, then H0ξ H + ζ H- (H-H)/2; xi represents the imbibition height harmony first parameter; ζ represents the imbibition height harmonic second parameter; ξ + ζ ═ 1;
if | H-H | > H0And H < H, then H0＝ξH+ζh-(h-H)/2。
In conclusion, due to the adoption of the technical scheme, the method has the advantages of simple steps, high installation speed, convenience and quickness in use and easiness in mastering; the measurement of the imbibition height is realized.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
FIG. 1 is a schematic diagram of the present invention.
Fig. 2 is a schematic structural diagram of the present invention.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.
The invention provides a testing device for measuring the imbibition height of a reverse imbibition experiment, which comprises an iron stand 6, wherein a glass tube 2 (also called a test tube) with two open ends is arranged on the iron stand 6, test tube scales for reading are arranged on the test tube, two non-intersecting resistance wires without insulation wrapping are arranged in the glass tube 2, the resistance wires are respectively a resistance wire 1a without insulation wrapping and a resistance wire 1b without insulation wrapping, wherein, the resistance wire 1a is fixed on the inner wall of the glass tube 2, the resistance wire 1b is arranged in the center of the glass tube 2, the first end of the resistance wire 1a and the first end of the resistance wire 1b are level with the lower port of the glass tube 2, the second end of the resistance wire 1a and the second end of the resistance wire 1b are level with the upper port of the glass tube 2, the second end of the resistance wire 1a is connected with the first end of a test input of a display instrument 9 through the wire 1, the second end of the second resistance wire 1b is connected with the second test input end of the display instrument 9 through a second wire, and the data end of the display instrument 9 is connected with the computer 10;
the bottom of the glass tube 2 is wrapped by filter paper 4 and fixed by a rubber band 3; the glass tube 2 is filled with an object to be detected, the object to be detected is pulverized coal with the same particle or different particle diameters, the water container 5 is placed at the bottom of the glass tube 2, and the water container 5 is filled with a conducting liquid capable of conducting the first resistance lead 1a and the second resistance lead 1 b; the conducting liquid is not limited to sodium chloride aqueous solution or potassium chloride aqueous solution, but also can be other types of conductive solutions, or aqueous solutions, and in order to facilitate the direct reading of the scales on the test tube by human eyes, a coloring agent, such as a red indicator or a purple indicator, is added into the conducting liquid; similarly, a coloring agent is added to the liquid for conducting inside the burette 71.
The device also comprises a liquid level titration device 7, and the liquid level of the conducting liquid in the water containing vessel 5 can be flush with the bottom of the glass tube 2 through the liquid level titration device 7.
In a preferred embodiment of the present invention, the liquid level titration apparatus 7 comprises a titration tube 71 disposed at the upper end of the water container 5 and a titration system for controlling titration of the titration tube 71, the titration system comprises a float 81 disposed in the water container 5, one end of a constraint line is disposed at the central position of the bottom of the float 81, the constraint line is a flexible line with certain elasticity, and can keep the horizontal position of the float 81 from changing according to the liquid level, the other end of the constraint line is disposed at the inner bottom of the water container 5, and a communication body 82 is disposed at the top of the float 81; the via 82 is a conductor, and may be a small iron block or an aluminum block.
The upper end of the water containing vessel 5 is also provided with a first electrode 83 and a second electrode, the first electrode 83 is connected with the first input end of the control module through a first connecting lead 84, and the second electrode is connected with the second input end of the control module through a second connecting lead; wherein, a lifting frame 8 for adjusting the height between the first electrode 83 and the second electrode and the liquid level and a titration lifting frame for adjusting the height between the burette 71 and the liquid level are arranged beside the iron stand 6.
When the liquid level in the water container 5 causes the buoy 81 to lift the communicating body 82 and simultaneously contact with the first electrode 83 and the second electrode, the control module controls the burette 71 to stop titrating the conducting liquid into the water container 5; at the moment, the liquid level is coincided with the bottom height of the test tube, the pulverized coal in the test tube just absorbs the conducting liquid in the water containing vessel 5, and the heights of the first electrode 83 and the second electrode can be adjusted according to actual conditions, so that the test tube can submerge different height positions.
When the connecting body 82 of the titration tube is not simultaneously contacted with the first electrode 83 and the second electrode, the control module controls the titration tube 71 to titrate the conducting liquid into the water containing vessel 5; until the via 82 contacts both the first electrode 83 and the second electrode.
In a preferred embodiment of the present invention, the control module comprises a solenoid valve for controlling the titration of the conductive liquid into the water container 5 and a flow metering valve for metering the volume of the titration conductive liquid into the water container 5 arranged at the titration portion of the burette 71 or/and a graduation line for reading the volume of the titration conductive liquid into the water container 5 arranged at the burette 71 tube body, a first end of a relay input loop is connected with the 3.3V power supply, a second end of the relay input loop is connected with a collector of a triode, an emitter of the triode is connected with a first end of a current limiting resistor, a second end of the current limiting resistor is connected with the power ground, a base of the triode is connected with the titration control end of the titration controller, a detection input end of the titration controller is respectively connected with a first connecting wire 84 and a first end of a first divider resistor, a second end of the first divider resistor is connected with the power ground, and a second connecting wire is connected with the first end of the second divider resistor, the second end of the first divider resistor is connected with a 3.3V power supply, a normally open contact of the relay is connected in series in a power supply loop of the electromagnetic valve, the flow data output end of the flow metering valve is connected with the flow data input end of the titration controller, and the flow data end of the titration controller is connected with the computer 10.
In a preferred embodiment of the present invention, the iron stand 6 includes a base 63, a vertical lifting rod 62 is provided on the base 63, and a horizontal lifting clamp 61 capable of adjusting height up and down is provided on the vertical lifting rod 62; the glass tube 2 is vertically clamped on the horizontal lifting clamp 61, and the water containing vessel 5 is arranged on the base 63.
In a preferred embodiment of the present invention, the display instrument 9 includes a housing and a display screen disposed on the surface of the housing, a PCB circuit board fixing mount for fixedly mounting a PCB circuit board is disposed in the housing, the PCB circuit board is fixedly mounted on the PCB circuit board fixing mount, a voltage detection unit for detecting a voltage value between the resistance wires and a current detection unit for detecting a current value between the resistance wires are disposed on the PCB circuit board, and a controller, a data transmission unit and a power supply voltage adjustment unit are disposed on the PCB circuit board;
a first power output end of the power supply voltage regulating unit is connected with a first end of the current-limiting resistor, a second end of the current-limiting resistor is connected with a first test input end of the display instrument 9, a second power output end of the power supply voltage regulating unit is connected with a second test input end of the display instrument 9, a voltage regulating end of the power supply voltage regulating unit is connected with a voltage regulating end of the controller, and a voltage regulating signal is sent to the power supply voltage regulating unit through the controller to change the power supply voltage output by the power supply voltage regulating unit;
a detection loop of the voltage detection unit is connected with the resistance wire in parallel, namely a voltage detection first end of the voltage detection unit is connected with a test input first end of the display instrument 9, a voltage detection second end of the voltage detection unit is connected with a test input second end of the display instrument 9, and a voltage data output end of the voltage detection unit is connected with a voltage data input end of the controller; the detection circuit of the current detection unit is connected in series in the resistance wire circuit, the current data output end of the current detection unit is connected with the current data input end of the controller, the data transmission end of the controller is connected with the data transmission end of the data transmission unit, and the data display end of the controller is connected with the data display end of the display screen;
the method for calculating the imbibition height of the imbibition height comprises the following steps:
firstly, the controller controls the power supply voltage regulating unit to output power supply voltage U in a detection period1～UTWherein U isjIs less than Uj+1A positive number of; u shapej+1-UjaV; v represents the voltage sign volt, a is a positive number greater than 0, preferably 0.1 or 0.2; j is 1, 2, 3, … …, T-1; t is a positive integer greater than or equal to 2; in the present embodiment, T is 10, U1For the 1 st output supply voltage, U2For the 2 nd output supply voltage, U3For the 3 rd output supply voltage, U4For the 4 th output supply voltage, U5For the 5 th output supply voltage, U6For the 6 th output supply voltage, U7For the 7 th output supply voltage, U8For the 8 th output supply voltage, U9For the 9 th output supply voltage, U10For the 10 th output of the power supply voltage, U1<U2<U3<U4<U5<U6<U7<U8<U9<U10。
The second step, the output power voltage of the power supply voltage regulating unit is UiWhen i is 1, 2, 3, … …, T; calculating the resistance value of the resistance wire:
Figure GDA0003597595680000111
wherein, the first and the second end of the pipe are connected with each other,
Figure GDA0003597595680000112
indicating that the output power supply voltage of the power supply voltage regulating unit is UiThen, the voltage value detected by the voltage detection unit;
Figure GDA0003597595680000113
indicating that the output power supply voltage of the power supply voltage regulating unit is UiThen, the current value detected by the current detection unit;
t represents the number of different power supply voltages output by the power supply voltage regulating unit;
Figure GDA0003597595680000114
representing a resistance value measured in the measurement loop;
Figure GDA0003597595680000115
wherein R is0The resistance value between the first resistance lead 1a and the second resistance lead 1b is shown;
r represents the resistance value of the resistance wire in the loop;
R0＝(1-φ)ηl，
wherein, phi represents an error coefficient, and phi belongs to (0, 0.115);
eta represents the conduction rate of the conduction liquid between the first resistance lead 1a and the second resistance lead 1 b;
l represents the distance between the first resistance lead 1a and the second resistance lead 1 b;
Figure GDA0003597595680000121
wherein epsilon represents the resistivity of the resistance wire;
l represents the length of the resistance wire in the glass tube 2, L ═ L1+L2，L1Indicates the length, L, of the resistance wire 1a2The length of the second resistance lead 1b is shown;
h represents the imbibition height displayed by the display instrument 9
S represents the cross-sectional area of the resistance wire;
thirdly, solving the imbibition height:
Figure GDA0003597595680000122
the invention also discloses a testing method of the testing device for measuring the imbibition height of the reverse imbibition experiment, which comprises the following steps:
s1, fixing the first resistance wire 1a without being wrapped by the insulating material on the inner wall of the glass tube 2, and placing the second resistance wire 1b without being wrapped by the insulating material in the center of the glass tube 2, or fixing the first resistance wire 1a and the second resistance wire 1b without being wrapped by the insulating material on the inner wall of the glass tube 2, wherein the first resistance wire 1a and the second resistance wire 1b are on the same circle center diameter, namely are symmetrical about the central axis of the glass tube 2; one ends of a first resistance lead 1a and a second resistance lead 1b are leveled with the bottom of the glass tube 2, and the other ends of the first resistance lead 1a and the second resistance lead 1b are respectively connected with the first lead 1 and the second lead and then led out of the glass tube 2;
s2, fixing the filter paper 4 at the bottom of the glass tube 2 through the rubber band 3, pouring coal powder from the upper end of the glass tube 2, vibrating the glass tube 2 to enable the coal powder to form a coal powder column with uniform density, and vertically clamping the glass tube 2 by using the transverse lifting clamp 61;
s3, injecting a certain amount of conducting liquid into the water containing vessel 5, horizontally placing the conducting liquid on the base 63, placing the buoy 81 with a small iron block on the top on the liquid level, adjusting the position of the lifting frame to enable the first electrode 83 and the second electrode to be just contacted with the small iron block, connecting the buoy switch with the control module through the first connecting wire 84 and the second connecting wire, and adjusting the position of the liquid injection port of the burette 71 to enable the position to be slightly higher than the liquid level; the float switch is composed of a first electrode 83, a second electrode and a communicating body 82.
S4, connecting the first resistance lead 1a and the second resistance lead 1b at the upper end of the glass tube 2 with the display instrument 9, and adjusting the height of the glass tube 2 to enable the bottom end of the glass tube 2 to be level with the liquid level;
when the liquid level rises to the original height again, the first electrode 83, the second electrode and the iron block are contacted with each other, and the burette 71 stops liquid injection at the moment;
meanwhile, the imbibition height is changed, the imbibition height is displayed in a digital mode through a display instrument 9 and is recorded in real time by a computer 10;
s5, the imbibition height calculated by the burette 71 and the imbibition height calculated by the display instrument 9 are mutually verified to obtain a more accurate imbibition height.
In a preferred embodiment of the present invention, in step S5, the calculation method of the imbibition height calculated by the burette 71 is as follows:
Figure GDA0003597595680000131
in the formula: vGeneral assembly-total volume of titration;
Vsteaming food-total volume of evaporation;
r-glass tube radius;
rho-the void ratio of coal powder accumulation;
h-imbibition height;
in step S5, the calculation method of the calculated suction height of the display meter 9 is:
Figure GDA0003597595680000141
wherein L denotes the length of the resistance wire in the glass tube 2, and L ═ L1+L2，L1Indicates the length, L, of the resistance wire 1a2The length of the second resistance lead 1b is shown;
s represents the cross-sectional area of the resistance wire;
ε represents the resistivity of the resistive wire;
t represents the number of different power supply voltages output by the power supply voltage regulating unit;
Figure GDA0003597595680000142
indicating that the output power supply voltage of the power supply voltage regulating unit is UiThen, the voltage value detected by the voltage detection unit;
Figure GDA0003597595680000143
indicating that the output power supply voltage of the power supply voltage regulating unit is UiThe current value detected by the current detection unit;
phi denotes an error coefficient, phi ∈ (0,0.115 ];
eta represents the conduction rate of the conduction liquid between the first resistance lead 1a and the second resistance lead 1 b;
l represents the distance between the first resistance lead 1a and the second resistance lead 1 b;
h represents the imbibition height indicated by the display instrument 9.
In a preferred embodiment of the present invention, in step S5, if | H-H | < ═ H0Wherein, H represents the imbibition height displayed by the display instrument 9, H-imbibition height; | | represents taking an absolute value; -represents less than or equal to; h0Representing a threshold value of a difference in imbibition height; then
Figure GDA0003597595680000144
h0Indicating the exact imbibition height;
if | H-H | > H0And H > H, then H0ξ H + ζ H- (H-H)/2; xi represents the imbibition height harmony first parameter; ζ represents the imbibition height harmonic second parameter; ξ + ζ ═ 1;
if | H-H | > H0And H < H, then H0＝ξH+ζh-(h-H)/2。
While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims (7)

1. A testing device for measuring the permeation height of a reverse permeation experiment is characterized by comprising an iron stand, wherein a glass tube with openings at two ends is arranged on the iron stand, two mutually non-intersecting resistance wires without insulation wrapping are arranged in the glass tube and respectively comprise a first resistance wire and a second resistance wire, one end of the first resistance wire is connected with a first test input end of a display instrument through the first resistance wire, one end of the second resistance wire is connected with a second test input end of the display instrument through the second resistance wire, and a data end of the display instrument is connected with a computer;
the bottom of the glass tube is wrapped by filter paper and fixed by a rubber band; the glass tube is filled with an object to be detected, the water container is placed at the bottom of the glass tube, and the water container is filled with a conducting liquid capable of conducting the first resistance lead and the second resistance lead;
the titration system comprises a buoy arranged in the water containing vessel, one end of a binding line is arranged at the center of the bottom of the buoy, the other end of the binding line is arranged at the inner bottom of the water containing vessel, and a communicating body is arranged at the top of the buoy;
the upper end of the water containing vessel is also provided with a first electrode and a second electrode, the first electrode is connected with the first input end of the control module through a first connecting wire, and the second electrode is connected with the second input end of the control module through a second connecting wire;
when the liquid level in the water container makes the buoy support the communicating body and simultaneously contact with the first electrode and the second electrode, the control module controls the burette to stop titrating the conducting liquid into the water container;
when the communicating body of the titration tube is not simultaneously contacted with the first electrode and the second electrode, the control module controls the titration tube to titrate the conducting liquid into the water containing vessel; until the communicating body is simultaneously contacted with the first electrode and the second electrode;
the liquid level of the conducting liquid in the water containing vessel can be leveled with the bottom of the glass tube through the liquid level titration device.
2. The testing device for measuring the imbibition height in the reverse imbibition experiment of claim 1, wherein the control module comprises a solenoid valve for controlling the titration conduction liquid to the water container and a flow metering valve for metering the titration conduction liquid volume to the water container arranged at the titration portion of the burette or/and a graduation line for reading the titration conduction liquid volume in the water container arranged at the burette body, a first end of a relay input loop is connected with a 3.3V power supply, a second end of the relay input loop is connected with a collector electrode of a triode, an emitter electrode of the triode is connected with a first end of a current-limiting resistor, a second end of the current-limiting resistor is connected with a power ground, a base electrode of the triode is connected with a titration control end of the titration controller, a detection input end of the titration controller is respectively connected with a first connecting wire and a first end of a first divider resistor, the second end of the first divider resistor is connected with a power ground, the second connecting wire is connected with the first end of the second divider resistor, the second end of the first divider resistor is connected with a 3.3V power supply, the normally open contact of the relay is connected in series in a power supply loop of the electromagnetic valve, the flow data output end of the flow metering valve is connected with the flow data input end of the titration controller, and the flow data end of the titration controller is connected with the computer.
3. The test device for measuring the imbibition height in the reverse imbibition experiment of claim 1, wherein the iron stand comprises a base, a vertical lifting rod is arranged on the base, and a transverse lifting clamp capable of adjusting the height up and down is arranged on the vertical lifting rod; the glass tube is vertically clamped on the transverse lifting clamp, and the water containing vessel is arranged on the base.
4. The test device for measuring the imbibition height in the reverse imbibition experiment of claim 1, wherein the display instrument comprises a shell and a display screen arranged on the surface of the shell, a PCB fixed mounting seat for fixedly mounting a PCB is arranged in the shell, the PCB is fixedly mounted on the PCB fixed mounting seat, a voltage detection unit for detecting the voltage value between the resistance wires and a current detection unit for detecting the current value between the resistance wires are arranged on the PCB, and the controller, the data transmission unit and the power supply voltage regulation unit are arranged on the PCB;
the power supply output first end of the power supply voltage regulating unit is connected with the first end of the current limiting resistor, the second end of the current limiting resistor is connected with the test input first end of the display instrument, the power supply output second end of the power supply voltage regulating unit is connected with the test input second end of the display instrument, the voltage regulating end of the power supply voltage regulating unit is connected with the voltage regulating end of the controller, and the controller sends a voltage regulating signal to the power supply voltage regulating unit to change the power supply voltage output by the power supply voltage regulating unit;
a detection loop of the voltage detection unit is connected with the resistance wire in parallel, namely, a voltage detection first end of the voltage detection unit is connected with a test input first end of the display instrument, a voltage detection second end of the voltage detection unit is connected with a test input second end of the display instrument, and a voltage data output end of the voltage detection unit is connected with a voltage data input end of the controller; the detection circuit of the current detection unit is connected in series in the resistance wire circuit, the current data output end of the current detection unit is connected with the current data input end of the controller, the data transmission end of the controller is connected with the data transmission end of the data transmission unit, and the data display end of the controller is connected with the data display end of the display screen;
the method for calculating the imbibition height of the imbibition height comprises the following steps:
firstly, the controller controls the power supply voltage regulating unit to output the power supply voltage U in the detection period1～UTWherein U isjIs less than Uj+1A positive number of; j is 1, 2, 3, … …, T-1; t is a positive integer greater than or equal to 2;
the second step, the output power voltage of the power supply voltage regulating unit is UiWhen i is 1, 2, 3, … …, T; calculating the resistance value of the resistance wire:
Figure FDA0003597595670000031
wherein T represents the number of different power supply voltages output by the power supply voltage regulating unit;
Figure FDA0003597595670000032
representing a resistance value measured in the measurement loop;
Figure FDA0003597595670000033
wherein R is0The resistance value of the first resistance wire and the second resistance wire is represented;
r represents the resistance value of the resistance wire in the loop;
R0＝(1-φ)ηl，
where φ represents an error coefficient, φ ∈ (0,0.115 ];
eta represents the conduction rate of the conduction liquid between the first resistance lead and the second resistance lead;
l represents the distance between the first resistance wire and the second resistance wire;
Figure FDA0003597595670000034
wherein epsilon represents the resistivity of the resistance wire;
l represents the length of the resistance wire in the glass tube, L ═ L1+L2，L1Indicates the length of the first resistance wire, L2The length of the second resistance lead is shown;
h represents the imbibition height displayed by the display instrument
S represents the cross-sectional area of the resistance wire;
thirdly, solving the imbibition height:
Figure FDA0003597595670000041
5. the testing method of the testing device for measuring the imbibition height in the reverse imbibition experiment according to any one of claims 1 to 4, comprising the following steps:
s1, fixing the first resistance wire without insulation coating on the inner wall of the glass tube, placing the second resistance wire without insulation coating in the center of the glass tube, enabling one ends of the first resistance wire and the second resistance wire to be level with the bottom of the glass tube, and leading out the glass tube after the other ends of the first resistance wire and the second resistance wire are respectively connected with the first resistance wire and the second resistance wire;
s2, fixing filter paper at the bottom of a glass tube through a rubber band, pouring coal powder from the upper end of the glass tube, vibrating the glass tube to enable the coal powder to form a coal powder column with uniform density, and vertically clamping the glass tube by using a transverse lifting clamp;
s3, injecting a certain amount of conducting liquid into the water containing vessel, horizontally placing the conducting liquid on the base, placing the buoy with the top provided with the small iron block on the liquid level, adjusting the position of the lifting frame to enable the electrode I and the electrode II to be just contacted with the small iron block, connecting the buoy switch with the control module through the connecting wire I and the connecting wire II, and adjusting the position of the liquid injection port of the burette to be slightly higher than the liquid level;
s4, connecting the first resistance lead and the second resistance lead at the upper end of the glass tube with a display instrument, and adjusting the height of the glass tube to enable the bottom end of the glass tube to be level with the liquid level;
when the liquid level rises to the original height again, the first electrode and the second electrode contact with the iron block, and the burette stops injecting liquid;
meanwhile, the imbibition height is changed, the imbibition height is displayed in a digital mode through a display instrument and is recorded in real time by a computer;
and S5, mutually verifying the calculated imbibition height through the burette and the imbibition height calculated by the display instrument to obtain more accurate imbibition height.
6. The method for testing the testing device of measuring the imbibition height in the reverse imbibition experiment of claim 5, wherein in step S5, the computing method of the imbibition height computed by the burette is as follows:
Figure FDA0003597595670000051
in the formula: vGeneral assembly-total volume of titration;
Vsteaming food-total volume of evaporation;
r-glass tube radius;
rho-the void ratio of coal powder accumulation;
h-imbibition height;
in step S5, the calculation method of the calculated suction height of the display meter is:
Figure FDA0003597595670000052
wherein L represents the length of the resistance wire in the glass tube, and L is L1+L2，L1Indicates the length of the first resistance wire, L2The length of the second resistance lead is shown;
s represents the cross-sectional area of the resistance wire;
ε represents the resistivity of the resistive wire;
t represents the number of different power supply voltages output by the power supply voltage regulating unit;
Figure FDA0003597595670000061
indicating that the output power supply voltage of the power supply voltage regulating unit is UiThen, the voltage value detected by the voltage detection unit;
Figure FDA0003597595670000062
indicating that the output power supply voltage of the power supply voltage regulating unit is UiThe current value detected by the current detection unit;
phi denotes an error coefficient, phi ∈ (0,0.115 ];
eta represents the conduction rate of the conduction liquid between the first resistance wire and the second resistance wire;
l represents the distance between the first resistance wire and the second resistance wire;
h represents the imbibition height indicated by the display meter.
7. The method for testing a device for measuring the wicking height in reverse wicking experiments of claim 5, wherein in step S5, if | H-H | < ═ H |0Wherein H represents the imbibition height displayed by a display instrument, H-imbibition height; | | represents taking an absolute value; -represents less than or equal to; h0Representing a threshold value of the difference of imbibition heights; then
Figure FDA0003597595670000063
h0Indicating the exact imbibition height;
if | H-H | > H0And H > H, then H0ξ H + ζ H- (H-H)/2; ξ represents the imbibition height harmony first parameter; ζ represents the imbibition height harmonic second parameter; ξ + ζ ═ 1;
if | H-H | > H0And H < H, then H0＝ξH+ζh-(h-H)/2。
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