An apparatus and a testing method for determining the variation law of water film distribution during the pressurization process

Abstract

The present invention provides a device and a test method for measuring the variation law of water film distribution during the pressurization process. The device includes a test stand, a base, a handwheel, a lifting table, a soil body, a dial indicator, a backing plate, a plastic plate, a chip, an electrode plate, a sample cylinder, wire a, wire b, a piston, and a plastic bearing platform; the inside of the electrode plate is divided into several metal blocks according to a radial distribution, and the metal blocks are separated by an electrically insulating material; the chip is placed on the upper surface of the electrode plate and serves to control the cyclic power supply of each metal block of the electrode plate; the device divides the electrode plate into independent test units, measures the water film area at the corresponding positions respectively, and thus determines the water film distribution under the electrode plate; this provides an analysis basis for studying the law of the increase in the adhesion between the soil-metal interface during the pressurization process and provides a theoretical support for reducing adhesion and resistance during mechanical construction in clay formations.

Description

Technical Field

[0001] The present invention belongs to the technical field of agricultural machinery construction for reducing viscosity and resistance, and particularly relates to a device and a test method for measuring the change law of the water film distribution during the pressurization process. Background Art

[0002] The adhesion of wet soil to the soil-contact components of ground machinery is a common problem, which seriously affects the working efficiency of ground machinery. Fundamentally speaking, soil adhesion is an interfacial phenomenon and is the result of physical, chemical, and mechanical interactions between the soil-contact components and the soil. For a long time, people have studied the mechanism of soil adhesion from different perspectives and put forward various theories and doctrines, such as Foutaine's water tension theory, Zisman's capillary theory, Fisher's water film medium theory, etc. A large number of research results show that the soil adhesion force mainly depends on the water film tension at the interface, and the change in soil moisture content has a great influence on the adhesion force. The adhesion force changes in a parabolic law with the increase in moisture content. Therefore, the properties, morphology, and distribution of the water film at the soil-metal interface are extremely important factors affecting the soil adhesion force. At present, the research on the mechanism and law of soil adhesion at home and abroad is still in the stage of qualitative analysis, which greatly restricts the in-depth development of soil anti-adhesion and desorption theories and technologies.

[0003] It is found through retrieval that the patent with the application number 202020176887.0, "A Rotary Drilling Bucket with Anti-adhesion Function", provides a rotary drilling bucket with anti-adhesion function. An irregular non-smooth wall surface is designed on the inner wall surface of the drill barrel, which can increase the disturbance of the soil in the drill barrel, break the water film on the surface of the muddy soil, thereby reducing the soil adhesion amount on the inner surface of the drill barrel and improving the operation efficiency of the machine. This patent reduces the soil adhesion amount on the metal surface by breaking the water film. The papers "Concentration Polarization Method for Measuring the Water Film at the Soil-Metal Interface" and "Experimental Study on the Adhesion Law of the Water Film at the Soil-Metal Interface" used the concentration polarization method to measure the thickness and area of the water film at the soil-metal interface. However, this method cannot obtain the distribution law of the water film at the soil-metal interface. Therefore, it is impossible to determine that during the pressurization process, the water in the soil migrates and aggregates to different positions at the interface to form a water film, nor can it determine the growth law of the adhesion force at different positions at the interface. It can neither reveal the mechanism of the adhesion force growth at the interface from the perspective of the water film distribution evolution, nor establish a quantitative model between the adhesion force growth at the interface and the water film distribution at the interface. Summary of the Invention

[0004] The object of the present invention is to solve the deficiencies and defects existing in the prior art, and provides a device and a test method for measuring the change law of the water film distribution during the pressurization process. By dividing the electrode plate into independent test units and measuring the water film area at the corresponding positions respectively, the water film distribution under the electrode plate can be determined; this provides an analysis basis for studying the bonding growth law between the soil-metal interface during the pressurization process and provides a theoretical support for reducing adhesion and resistance during mechanical construction in clay strata.

[0005] A device for measuring the change law of the water film distribution during the pressurization process, including a test stand 1, a base 2, a handwheel 3, a lifting table 4, a soil mass 5, a dial indicator 6, a backing plate 7, a plastic plate 8, a chip 9, an electrode plate 10, a sample cylinder 11, a wire a 12, a wire b 13, a piston 14, and a plastic bearing platform 15;

[0006] The test stand 1 and the base 2 are connected as a whole through a rigid joint;

[0007] The handwheel 3 is connected to the base 2. By rotating the handwheel 3, the piston 14 and the plastic bearing platform 15 in the lifting table 4 can be controlled to move up and down, so as to achieve the purpose of pushing the sample cylinder 11 to lift and lower;

[0008] The sample cylinder 11 is placed directly above the plastic bearing platform 15; the soil mass 5 is contained inside the sample cylinder 11, the side wall is made of plastic material, and the bottom is a metal bottom plate. The metal bottom plate is connected to the positive pole of the current through the wire b 13;

[0009] The plastic plate 8 is fixed directly below the middle rod of the test stand 1;

[0010] The electrode plate 10 is fixed to the lower part of the plastic plate 8 by strong glue. The electrode plate 10 is divided into several metal blocks according to a radial distribution inside, and the metal blocks are separated by electrical insulation materials;

[0011] The chip 9 is placed on the upper surface of the electrode plate 10, which plays a role in controlling the cyclic power supply of each metal block inside the electrode plate 10, and the upper part is connected to the negative pole of the current through the wire a 12;

[0012] The dial indicator 6 is fixed at an appropriate position on the right rod of the test stand 1, so that the pointer at the lower end of the dial indicator 6 just touches the top surface of the backing plate 7 placed on the surface of the soil mass 5;

[0013] A test method for measuring the change law of the water film distribution during the pressurization process, which is connected by using the above-mentioned device for measuring the change law of the water film distribution during the pressurization process. The specific steps are as follows:

[0014] ① Fix the test stand 1, the base 2 and the lifting table 4 and place them on the experimental table;

[0015] ② Prepare a soil mass 5 with a water content of w, stir it evenly and then compact it in layers into the sample cylinder 11;

[0016] ③Slowly place the sample cylinder 11 on the plastic bearing platform 15 inside the lifting table 4 and fix it firmly.

[0017] ④Rotate the handwheel 3 to make the top layer of the soil mass 5 just touch the lower surface of the electrode plate 10, and record the reading of the dial gauge 6 at this time.

[0018] ⑤Rotate the handwheel 3 again to make the lifting table 4 continue to rise a small distance L, and record the reading of the dial gauge 6 at this time.

[0019] ⑥Connect and turn on the power supply. The chip 9 controls each metal plate inside the electrode plate 10 to supply power cyclically in sequence, and measure the current value i l ; According to the formula calculate the water film area S, where C° is the oxygen content of soil moisture, is the diffusion coefficient, i l is the unsteady diffusion current, S is the water film area at the interface; F is the Faraday constant;

[0020] ⑦Repeat the operations in step ⑤ and step ⑥, measure the data of the water film area S under 3 - 5 different pressurization strokes. According to the values of L and S, plot the curve of the change of the water film area S with the pressurization displacement L; thus analyze the change law of the water film distribution in the soil mass during the pressurization process.

[0021] Furthermore, the water film distribution at the soil - metal interface is closely related to the magnitude of the adhesion force at the interface. According to the change law of the water film distribution at the soil - metal interface during the pressurization process, it provides an analysis basis for studying the adhesion growth law between the soil and the metal during the pressurization process, and provides a theoretical support for reducing adhesion and resistance in mechanical construction in clay strata.

[0022] Beneficial effects

[0023] The present invention provides a device and a test method for measuring the change law of the water film distribution during the pressurization process. The device includes a test stand 1, a base 2, a handwheel 3, a lifting table 4, a soil mass 5, a dial gauge 6, a backing plate 7, a plastic plate 8, a chip 9, an electrode plate 10, a sample cylinder 11, a wire a 12, a wire b 13, a piston 14, and a plastic bearing platform 15; by dividing the electrode plate into independent test units, the water film areas at the corresponding positions are measured respectively, so as to determine the water film distribution situation below the electrode plate; this provides an analysis basis for studying the adhesion growth law between the soil and the metal during the pressurization process, and provides a theoretical support for reducing adhesion and resistance in mechanical construction in clay strata.

[0024] The advantages of the present invention are as follows:

[0025] ①It can measure the water film distribution situation at different positions at the soil - metal interface, and provide an analysis basis for analyzing the magnitude of the adhesion force at different positions at the interface;

[0026] ② It can provide an analysis basis for studying the law of bond growth between soil and metal during the pressurization process according to the evolution law of the water film distribution at the soil-metal interface;

[0027] ③ It can provide an analysis basis for the debonding design of the metal surface and a simple verification method for the effectiveness of debonding. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is the front view of the device structure described in the present invention.

[0029] Figure 2 It is the cross-sectional view of the plastic plate and the electrode plate described in the present invention.

[0030] Figure 3 It is the layout diagram of the metal blocks inside the electrode plate described in the present invention.

[0031] Figure 4 It is the cross-sectional view of the specimen cylinder described in the present invention.

[0032] Reference numeral description: test stand 1, base 2, handwheel 3, lifting table 4, soil body 5, dial indicator 6, backing plate 7, plastic plate 8, chip 9, electrode plate 10, specimen cylinder 11, wire a 12, wire b 13, piston 14, plastic bearing platform 15. SPECIFIC EMBODIMENTS

[0033] The present invention will be further described below in conjunction with the drawings and embodiments.

[0034] As Figure 1 shown, a device for measuring the change law of water film distribution during the pressurization process includes a test stand 1, a base 2, a handwheel 3, a lifting table 4, a soil body 5, a dial indicator 6, a backing plate 7, a plastic plate 8, a chip 9, an electrode plate 10, a specimen cylinder 11, a wire a 12, a wire b 13, a piston 14, and a plastic bearing platform 15;

[0035] The test stand 1 and the base 2 are connected as a whole through a rigid joint;

[0036] The handwheel 3 is connected to the base 2. Rotating the handwheel 3 can control the up and down movement of the piston 14 and the plastic bearing platform 15 inside the lifting table 4 to achieve the purpose of pushing the specimen cylinder 11 up and down;

[0037] The specimen cylinder 11 is placed directly above the plastic bearing platform 15; the soil body 5 is contained inside the specimen cylinder 11, the side wall is made of plastic material, and the bottom is a metal bottom plate. The metal bottom plate is connected to the positive pole of the current through the wire b 13;

[0038] The plastic plate 8 is fixed directly below the middle member of the test stand 1;

[0039] The electrode plate 10 is fixed to the lower part of the plastic plate 8 with strong glue. The inside of the electrode plate 10 is divided into several metal blocks distributed radially, and the metal blocks are separated by electrically insulating materials;

[0040] The chip 9 is placed on the upper surface of the electrode plate 10, which serves to control the cyclic power supply to each metal block within the electrode plate 10, and its upper part is connected to the negative pole of the current through the wire a12;

[0041] The dial indicator 6 is fixed at an appropriate position on the right rod of the test stand 1, such that the pointer at the lower end of the dial indicator 6 just touches the top surface of the backing plate 7 placed on the surface of the soil mass 5;

[0042] A test method for determining the variation law of the water film distribution during the pressurization process is connected with the device for determining the variation law of the water film distribution during the pressurization process as described above. The specific steps are as follows:

[0043] ① Fix the test stand 1, the base 2, and the lifting platform 4 and place them on the experimental table;

[0044] ② Prepare a soil mass 5 with a water content of w, mix it evenly and compact it in layers into the sample cylinder 11;

[0045] ③ Slowly place the sample cylinder 11 on the plastic bearing platform 15 inside the lifting platform 4 and fix it; as Figure 4 shown.

[0046] ④ Turn the handwheel 3 to make the top layer of the soil mass 5 just contact the lower surface of the electrode plate 10, and record the reading of the dial indicator 6 at this time;

[0047] ⑤ Turn the handwheel 3 again to make the lifting platform 4 continue to rise a small distance L, and record the reading of the dial indicator 6 at this time;

[0048] ⑥ Connect and turn on the power supply. The chip 9 controls the cyclic power supply to each metal plate within the electrode plate 10 in sequence, and measure the current value i l ; According to the formula calculate the water film area S, where C° is the soil moisture oxygen content, is the diffusion coefficient, i l is the unsteady diffusion current, S is the water film area at the interface; F is the Faraday constant; as Figure 2 、 Figure 3 shown;

[0049] ⑦ Repeat the operations in step ⑤ and step ⑥, measure the data of the water film area S under 3 - 5 different pressurization strokes, and draw a curve of the water film area S varying with the pressurization displacement L according to the values of L and S; thereby analyzing the variation law of the water film distribution in the soil mass during the pressurization process.

[0050] The above are only the preferred embodiments of the technology of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and replacements can be made, and these improvements and replacements should also be regarded as the protection scope of the present invention.

Claims

1. An apparatus for measuring the variation law of the water film distribution during the pressurization process, characterized in that, It includes a test stand (1), a base (2), a handwheel (3), a lifting platform (4), soil mass (5), dial gauges (6), cushion plates (7), plastic plates (8), chips (9), electrode plates (10), sample cylinders (11), wire a (12), wire b (13), pistons (14), and plastic bearing platforms (15); The test stand (1) and the base (2) are connected as a whole through rigid joints; The handwheel (3) is connected to the base (2). The handwheel (3) is used to drive the transmission inside the base (2), thereby controlling the up and down movement of the piston (14) and the plastic bearing platform (15) inside the lifting platform (4) to achieve the purpose of pushing the sample cylinder (11) to lift and lower; The sample cylinder (11) is placed directly above the plastic bearing platform (15); the soil mass (5) is contained inside the sample cylinder (11), the side wall is made of plastic material, and the bottom is a metal base plate, and the metal base plate is connected to the positive pole of the current through wire b (13); The plastic plate (8) is fixed directly below the middle member of the test stand (1); The electrode plate (10) is fixed to the lower part of the plastic plate (8) with strong glue. The electrode plate (10) consists of fan-shaped metal blocks distributed radially, and adjacent metal blocks are separated by electrical insulating materials; The chip (9) is placed on the upper surface of the electrode plate (10), which plays a role in controlling the cyclic power supply of each metal block inside the electrode plate (10), and the upper part is connected to the negative pole of the current through wire a (12); The dial gauge (6) is fixed at an appropriate position on the right member of the test stand (1) so that the pointer at the lower end of the dial gauge (6) just touches the top surface of the cushion plate (7) placed on the surface of the soil mass (5).

2. A test method for determining the variation law of the water film distribution during the pressurization process, characterized in that, Connect with the device for measuring the change law of the water film distribution during the pressurization process described in claim 1. The specific steps are as follows: ① Fix the test stand (1), the base (2), and the lifting platform (4) and place them on the experimental table; ② Prepare the soil mass (5) with a water content of w, stir it evenly and then compact it in layers into the sample cylinder (11); ③ Slowly place the sample cylinder (11) on the plastic bearing platform (15) inside the lifting platform (4) and fix it; ④ Turn the handwheel (3) to make the top layer of the soil mass (5) just touch the lower surface of the electrode plate (10), and record the reading of the dial gauge (6) at this time; ⑤ Turn the handwheel (3) again to make the lifting platform (4) continue to rise a small distance L, and record the reading of the dial gauge (6) at this time; ⑥Turn on and power on the device. The chip (9) controls each metal plate in the electrode plate (10) to supply power cyclically in sequence, and the current value i is measured. l ; Calculate the water film area S based on the current value. ⑦ Repeat the operations in step ⑤ and step ⑥, measure the data of the water film area S under 3 - 5 different pressurization strokes, and draw a curve of the water film area S changing with the pressurization displacement L according to the values of L and S; thereby analyzing the change law of the water film distribution in the soil mass during the pressurization process.

3. The method according to claim 2, wherein The water film distribution at the soil - metal interface is closely related to the magnitude of the bonding force at the interface. According to the change law of the water film distribution at the soil - metal interface during the pressurization process, it provides an analysis basis for studying the bonding growth law between the soil and the metal during the pressurization process, and provides a theoretical support for reducing adhesion and resistance during mechanical construction in clay strata.

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