An underwater automatic gas capture structure, test device and design method

Abstract

The present invention discloses an underwater automatic gas capture structure, test device and design method, comprising a water tank with an upper opening, a through hole at the bottom of the water tank, a super-hydrophobic closed cabin with a hemispherical structure above the through hole, the bottom of the super-hydrophobic closed cabin is sealed with the edge of the through hole, a plurality of air holes are opened on the super-hydrophobic closed cabin, a plurality of columns are evenly arranged on the surface of the super-hydrophobic closed cabin, the columns are perpendicular to the upper surface of the super-hydrophobic closed cabin; a CNT adhesion layer is arranged on the surface of the column. The design method comprises steps S1-S9. The structure of an underwater automatic gas capture proposed by the present invention is relatively simple in structure, the super-hydrophobic closed cabin forms a mesh spherical shell, the columns and gaps on the surface are the key structures for hydrophobic effect and gas exchange respectively; the preparation process and hydrophobic process of the structure are low in cost and high in efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of water-soluble gas utilization, and in particular to an underwater automatic gas capture structure, a test device and a design method. Background Art

[0002] The expansion of human activities has stimulated people's desire to develop the underwater world, such as underwater entertainment, rescue, life, etc. Therefore, how to prepare a structure that can breathe freely underwater like a fish has become a research hotspot. Bionic fish gills are a device that collects dissolved oxygen underwater and can meet human life activities underwater. At the same time, it has also been observed that insects can exchange gases underwater through bubbles, and it is proposed that underwater bubbles can serve as the lungs of organisms underwater, and the carbon dioxide in the bubbles exchanges gases with the dissolved oxygen in the water. Based on this, researchers have prepared a variety of bionic fish gills for humans to breathe underwater.

[0003] The designs in the prior art mostly include the following two types:

[0004] The first is a fish gill membrane that uses the difference in oxygen concentration on both sides of the membrane to eventually allow dissolved oxygen in the water to penetrate to the other side of the membrane and accumulate;

[0005] The second type is the funnel-shaped gill, which uses a composite polymer membrane to absorb oxygen from seawater and then collects it after releasing it through a weak electric current, ultimately achieving the function of a gill.

[0006] However, these bionic fish gills are expensive to prepare and complex to operate, which can easily lead to accidents due to improper operation by divers. In addition, the gills require additional power to obtain oxygen. Summary of the invention

[0007] In view of the above-mentioned deficiencies in the prior art, the present invention provides an underwater automatic gas capture structure, a test device and a design method for studying the ability to automatically capture gas from underwater.

[0008] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0009] Provided is an underwater automatic gas capture structure, which includes a super-hydrophobic closed cabin with a spherical structure, a plurality of air holes are opened on the super-hydrophobic closed cabin, and a plurality of columns are evenly arranged on the surface of the super-hydrophobic closed cabin, and the columns are perpendicular to the surface of the super-hydrophobic closed cabin;

[0010] The surface of the column is provided with a CNT adhesion layer, and the gaps between the columns form a hydrophobic spherical surface on the surface of the super-hydrophobic closed cabin. The hydrophobic spherical surface serves as a hydrophobic structural layer, and a stable air layer is formed in the hydrophobic structural layer. When the super-hydrophobic closed cabin is placed in water, the hydrophobic structural layer separates the surrounding liquid water from the interior of the super-hydrophobic closed cabin.

[0011] When there is a partial pressure gradient between the gas partial pressure in liquid water and the gas partial pressure in the superhydrophobic closed chamber, the gas dissolved in the water escapes into the superhydrophobic closed chamber, and at the same time, the mixed gas inside the superhydrophobic closed chamber dissolves in the liquid water through the pores, completing the gas exchange.

[0012] Furthermore, the super-hydrophobic closed cabin includes a plurality of annular support rods, which are evenly arranged from bottom to top, and the sizes of the support rods decrease successively from bottom to top to form the latitude of the hemispherical structure, and the support rods are connected by a plurality of curved rods, which are evenly distributed to form the warp of the hemispherical structure; and a plurality of columns are arranged on the latitude.

[0013] Furthermore, the material of the CNT adhesion layer includes a mixture of polydimethylsiloxane, a curing agent and acetone. The polydimethylsiloxane and the curing agent are insoluble in acetone. After the polydimethylsiloxane, the curing agent and the acetone are mixed and ultrasonically dispersed, the acetone solution becomes milky white and viscous. Thereafter, the acetone solution is evenly covered on the surface of the column through magnetic stirring to form a hydrophobic interface CNT adhesion layer.

[0014] Provided is a test device for the underwater automatic gas capture structure, characterized in that it comprises a water tank with an upper opening, a through hole is provided at the bottom of the water tank, a super-hydrophobic closed cabin with a hemispherical structure is provided above the through hole, and the bottom of the super-hydrophobic closed cabin with the hemispherical structure is sealed with the edge of the through hole;

[0015] A gas concentration sensor is arranged in the super-hydrophobic closed cabin, a gas hood is covered on the super-hydrophobic closed cabin, the upper end of the gas hood is connected with the gas pipe, and a water pipe is arranged on the upper end of the water tank.

[0016] Furthermore, the support rod at the lowermost end of the super-hydrophobic closed chamber of the hemispherical structure is fixed on the support ring, and the support ring is sealed and connected to the edge of the through hole.

[0017] Furthermore, a sealing cover is provided at the lower end of the through hole, the gas concentration sensor is installed in the sealing cover, the sealing cover is connected to the lower edge of the through hole through a sealing ring, and the wire of the gas concentration sensor passes through the sealing cover and is connected to the computer.

[0018] A method for designing the underwater automatic gas capture structure is provided, which comprises the following steps:

[0019] S1: Calculate the hydrostatic pressure P2 of the super-hydrophobic closed cabin at the designed underwater depth H:

[0020] P2=P1+ρgH

[0021] Wherein, P1 is the normal pressure of the superhydrophobic closed cabin, ρ is the density of water, and g is the acceleration of gravity;

[0022] S2: Establish the ideal gas equation for a super-hydrophobic closed chamber:

[0023]

[0024] Wherein, V1 is the volume of the air layer under normal pressure, V2 is the volume of the air layer under hydrostatic pressure, T1 is the temperature of the super-hydrophobic closed cabin under normal pressure, and T2 is the temperature of the super-hydrophobic closed cabin under hydrostatic pressure;

[0025] S3: Calculate the volume V2 of the super-hydrophobic closed chamber under hydrostatic pressure using the ideal gas equation and the hydrostatic pressure P2 formula:

[0026]

[0027] S4: According to the volume formula of a sphere Calculate the radius R2 of the air layer under hydrostatic pressure:

[0028]

[0029] Where R1 is the radius of the air layer at normal pressure;

[0030] S5: When the super-hydrophobic closed cabin descends to the depth H, the air layer on the surface is squeezed, and the reduced hydrophobic structure layer thickness ΔR satisfies:

[0031] ΔR=R1-R2≤l

[0032] Wherein, l is the thickness of the hydrophobic structure layer;

[0033] S6: Further obtain:

[0034]

[0035]

[0036] S7: Establish the relationship between the design radius R0 of the super-hydrophobic closed cabin, the radius R1 of the air layer under normal pressure and the thickness l of the hydrophobic structure layer:

[0037] R1=R0+l

[0038] S8: Combining the relationship in step S7 and step S6, we get:

[0039]

[0040] S9: According to the fact that the room temperature and water temperature in the experimental environment are equal, that is, T1=T2, the calculation method of the thickness l of the hydrophobic structure layer under the experimental conditions is obtained. The thickness l is the length of the column:

[0041]

[0042] The beneficial effects of the present invention are as follows: the hydrophobic structure layer of the present invention is composed of an array of columns of the same length, which are generally distributed on a plane. Liquid water cannot invade the gaps between the columns from the top of the columns, but it is easy to flow in from the gaps on the sides of the column array, causing the hydrophobic structure layer to collapse, resulting in the failure of the hydrophobic performance. However, the columns of the present invention are an array distributed on a spherical surface, and there is no problem of direct contact between the sides of the columns and liquid water, which can avoid the above-mentioned defects. Secondly, the super-hydrophobic closed cabin adopts a spherical mesh structure, which provides a transportation channel and storage space for the captured gas to enter the interior of the structure. The support ring plays a role of fixing and protecting. Finally, the mesh spherical shell forms a closed cabin to ensure that the gas only flows in the gaps between the support rods and the curved rods.

[0043] During the test, the super-hydrophobic closed chamber is fixed at the center of the bottom of the water tank, and there is a through hole at the center of the bottom of the water tank for placing the gas concentration sensor and the sealing cover. The gas concentration sensor is placed inside the sealing cover, and the sealing cover is close to the bottom of the water tank to ensure that the target gas measured by the gas concentration sensor only comes from the inside of the super-hydrophobic closed chamber. The water pipe and the gas pipe are introduced on both sides of the top of the water tank. The gas hood and the gas pipe are connected to form a gas supply device to ensure that the target gas concentration inside the super-hydrophobic closed chamber is at the set value before gas exchange. The gas concentration sensor can detect the concentration of the target gas in the air, and is connected to the computer through a wire to feedback the gas concentration value in real time.

[0044] The invention proposes a structure for automatic underwater gas capture, which has a relatively simple structure. A super-hydrophobic closed cabin forms a mesh spherical shell. The cylinder and the gap on the surface are key structures for hydrophobic effect and gas exchange, respectively. The hydrophobic structure layer and the mesh spherical shell provide exchange and storage places for gas, and the hydrophobic structure layer can withstand underwater high pressure. The preparation process and hydrophobic process of the structure are low in cost and high in efficiency. The design method of the super-hydrophobic closed cabin of the invention fully considers the conditions such as temperature and water pressure, so that the size of the hydrophobic structure layer can fully meet the conditions for gas exchange, and is designed according to the size of the super-hydrophobic closed cabin to meet the design requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a structural diagram of the underwater automatic gas capture structure test device.

[0046] Figure 2 This is a structural diagram of the super-hydrophobic closed cabin.

[0047] Figure 3 This is a cross-sectional view of the underwater automatic gas capture structure test device.

[0048] Figure 4 Graph showing oxygen capture underwater by a superhydrophobic closed chamber.

[0049] Among them, 1. gas pipe, 2. gas cover, 3. wire, 4. sealing cover, 5. gas concentration sensor, 6. super-hydrophobic closed cabin, 7. water tank, 8. water pipe, 9. column, 10. support ring, 11. support rod, 12. curved rod, 13. sealing ring. DETAILED DESCRIPTION

[0050] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0051] The underwater automatic gas capture structure of the present scheme includes a super-hydrophobic closed cabin 6 with a spherical structure, a plurality of air holes are opened on the super-hydrophobic closed cabin 6, and a plurality of columns 9 are evenly arranged on the surface of the super-hydrophobic closed cabin 6, and the columns 9 are perpendicular to the surface of the super-hydrophobic closed cabin 6.

[0052] A CNT adhesion layer is provided on the surface of the column 9, and the gaps between several columns 9 form a hydrophobic spherical surface on the surface of the super-hydrophobic closed cabin 6. The hydrophobic spherical surface serves as a hydrophobic structural layer, and a stable air layer is formed inside the hydrophobic structural layer. When the super-hydrophobic closed cabin 6 is placed in water, the hydrophobic structural layer separates the surrounding liquid water from the interior of the super-hydrophobic closed cabin 6.

[0053] When there is a partial pressure gradient between the gas partial pressure in liquid water and the gas partial pressure in the super-hydrophobic closed chamber 6, the gas dissolved in the water escapes into the super-hydrophobic closed chamber 6, and at the same time, the mixed gas inside the super-hydrophobic closed chamber 6 dissolves in the liquid water through the pores, completing the gas exchange.

[0054] like Figures 1 to 3 As shown, the test device of the underwater automatic gas capture structure of the present scheme includes a water tank 7 with an opening at the upper end, a through hole is arranged at the bottom of the water tank 7, a super-hydrophobic closed cabin 6 with a hemispherical structure is arranged above the through hole, the bottom of the super-hydrophobic closed cabin 6 with the hemispherical structure is sealed with the edge of the through hole, a plurality of air holes are opened on the super-hydrophobic closed cabin 6, and a plurality of columns 9 are evenly arranged on the surface of the super-hydrophobic closed cabin 6, and the columns 9 are perpendicular to the upper surface of the super-hydrophobic closed cabin 6.

[0055] A CNT adhesion layer is provided on the surface of the column 9, a gas concentration sensor 5 is provided in the super-hydrophobic closed cabin 6, an air hood 2 is covered on the super-hydrophobic closed cabin 6, the upper end of the air hood 2 is connected to the air pipe 1, and a water pipe 8 is provided at the upper end of the water tank 7; the gaps between the columns 9 form a hydrophobic spherical surface above the super-hydrophobic closed cabin 6, the hydrophobic spherical surface serves as a hydrophobic structural layer, and a stable air layer is formed in the hydrophobic structural layer. When the super-hydrophobic closed cabin 6 is placed in water, the hydrophobic structural layer separates the surrounding liquid water from the interior of the super-hydrophobic closed cabin 6.

[0056] When there is a partial pressure gradient between the gas partial pressure in liquid water and the gas partial pressure in the super-hydrophobic closed chamber 6, the gas dissolved in the water escapes into the super-hydrophobic closed chamber 6, and at the same time, the mixed gas inside the super-hydrophobic closed chamber 6 dissolves in the liquid water through the pores, completing the gas exchange.

[0057] In this embodiment, the super-hydrophobic closed cabin 6 includes a plurality of annular support rods 11, the plurality of support rods 11 are evenly arranged from bottom to top, and the size of the plurality of support rods 11 from bottom to top is reduced in sequence to form the latitude of the hemispherical structure, the plurality of support rods 11 are connected by a plurality of curved rods 12, and the plurality of curved rods 12 are evenly distributed to form the warp of the hemispherical structure; a plurality of cylinders 9 are arranged on the latitude. The support rods 11 at the bottom of the super-hydrophobic closed cabin 6 of the hemispherical structure are fixed on the support ring 10, and the support ring 10 is sealed and connected with the edge of the through hole. A sealing cover 4 is provided at the lower end of the through hole, and a gas concentration sensor 5 is installed in the sealing cover 4, and the sealing cover 4 is connected with the lower edge of the through hole through a sealing ring 13, and the wire 3 of the gas concentration sensor 5 passes through the sealing cover 4 and is connected to the computer.

[0058] In this embodiment, the material of the CNT adhesion layer includes a mixture of polydimethylsiloxane, a curing agent and acetone. The polydimethylsiloxane and the curing agent are insoluble in acetone. After the polydimethylsiloxane, the curing agent and the acetone are mixed and ultrasonically dispersed, the acetone solution becomes milky white and viscous. Thereafter, the acetone solution is evenly covered on the surface of the column 9 by magnetic stirring to form a hydrophobic interface CNT adhesion layer.

[0059] The hydrophobic structure layer of the present invention is composed of an array of cylinders 9 of the same length. The cylinder array 9 is usually distributed on a plane. Liquid water cannot invade the gaps between the cylinders 9 from the top of the cylinders 9, but it is easy to flow into the gaps on the sides of the cylinder array 9, causing the hydrophobic structure layer to collapse, resulting in the failure of hydrophobic performance. However, the cylinders 9 of the present invention are arrays distributed on a spherical surface, and there is no problem of direct contact between the sides of the cylinders 9 and liquid water, which can avoid the above-mentioned defects. Secondly, the super-hydrophobic closed cabin 6 adopts a spherical mesh structure, which provides a transportation channel and storage space for the captured target gas to enter the structure. The support ring 10 plays a fixing and protective role. Finally, the mesh spherical shell forms a closed cabin to ensure that the gas only flows in the gaps between the support rods 11 and the curved rods 12.

[0060] The super-hydrophobic closed cabin 6 is fixed at the bottom center of the water tank 7, and there is a through hole at the bottom center of the water tank 7 for placing the gas concentration sensor 5 and the sealing cover 4. The gas concentration sensor 5 is placed inside the sealing cover 4, and the sealing cover 4 is close to the bottom of the water tank 7, ensuring that the target gas measured by the gas concentration sensor 5 only comes from the inside of the super-hydrophobic closed cabin 6. The water pipe 8 and the gas pipe 1 are respectively introduced on both sides of the top of the water tank 7. The gas hood 2 and the gas pipe 1 are connected to form a gas delivery device to ensure that the target gas concentration inside the super-hydrophobic closed cabin 6 is at a set value before gas exchange. The gas concentration sensor 5 can detect the target gas concentration in the air, is connected to the computer through the wire 3, and the gas concentration value is fed back in real time.

[0061] The experimental process of the underwater automatic gas capture structure test device of this scheme includes (taking the capture of dissolved oxygen in water as an example):

[0062] 1) placing the super-hydrophobic closed chamber 6 in a water tank 7, and then inputting a mixed gas (nitrogen, carbon dioxide, oxygen) through a gas delivery device;

[0063] 2) When the gas concentration sensor 5 detects that the oxygen concentration inside the structure drops to about 13%, stop supplying gas;

[0064] 3) After adding water to the water tank 7 until the height completely submerges the super-hydrophobic closed cabin 6, the gas hood 2 is removed to allow the gas in the super-hydrophobic closed cabin 6 to exchange gas with the dissolved oxygen in the water.

[0065] The working principle of the super-hydrophobic closed chamber 6 automatically capturing oxygen in water is as follows (taking capturing dissolved oxygen in water as an example):

[0066] When the super-hydrophobic closed cabin 6 is in water, the gaps between the outermost column 9 arrays lock the air to form a stable air layer, and the edge of the air layer separates the mesh super-hydrophobic closed cabin 6 from the surrounding liquid water. At this time, the mixed gas in the super-hydrophobic closed cabin 6 and the air layer between the column 9 structural layers are equivalent to a bubble floating in the water. There is a partial pressure gradient between the partial pressure of oxygen dissolved in water and the partial pressure of oxygen in the bubble, so the oxygen dissolved in water will escape and enter the bubble, and at the same time, the mixed gas inside the bubble is dissolved in water through the mesh structure, thereby completing gas exchange. Figure 4 This is a curve chart of the super-hydrophobic closed cabin 6 capturing oxygen underwater. The oxygen concentration in the cabin gradually increases with time, which is consistent with the previous assumption.

[0067] The design method of the underwater automatic gas capture structure in this scheme includes the following steps:

[0068] S1: Calculate the hydrostatic pressure P2 of the super-hydrophobic closed cabin 6 at the designed underwater depth H:

[0069] P2=P1+ρgH

[0070] Wherein, P1 is the normal pressure of the super-hydrophobic closed cabin 6, ρ is the density of water, and g is the acceleration due to gravity;

[0071] S2: Establish the ideal gas equation for the super-hydrophobic closed chamber 6:

[0072]

[0073] Wherein, V1 is the volume of the air layer 6 under normal pressure, V2 is the volume of the air layer 6 under hydrostatic pressure, T1 is the temperature of the super-hydrophobic closed cabin 6 under normal pressure, and T2 is the temperature of the super-hydrophobic closed cabin 6 under hydrostatic pressure;

[0074] S3: Calculate the volume V2 of the super-hydrophobic closed chamber 6 under hydrostatic pressure using the ideal gas equation and the hydrostatic pressure P2 formula:

[0075]

[0076] S4: According to the volume formula of a sphere Calculate the radius R2 of the air layer under hydrostatic pressure:

[0077]

[0078] Where R1 is the radius of the air layer at normal pressure;

[0079] S5: When the super-hydrophobic closed chamber 6 descends to the depth H, the air layer on the surface is squeezed, and the reduced hydrophobic structure layer thickness ΔR satisfies:

[0080] ΔR=R1-R2≤l

[0081] Wherein, l is the thickness of the hydrophobic structure layer;

[0082] S6: Further obtain:

[0083]

[0084]

[0085] S7: Establish the relationship between the design radius R0 of the super-hydrophobic closed cabin 6, the radius R1 of the air layer under normal pressure and the thickness l of the hydrophobic structure layer:

[0086] R1=R0+l

[0087] S8: Combining the relationship in step S7 and step S6, we get:

[0088]

[0089] S9: According to the fact that the room temperature and the water temperature in the experimental environment are equal, that is, T1=T2, the calculation method of the thickness l of the hydrophobic structure layer under the experimental conditions is obtained. The thickness l is the length of the column 9:

[0090]

[0091] The present invention proposes a structure for automatically capturing gas underwater, which has a relatively simple structure. The super-hydrophobic closed cabin 6 forms a mesh spherical shell, and the cylinder 9 and the gap on the surface are the key structures for hydrophobic effect and gas exchange, respectively. The hydrophobic structure layer and the mesh spherical shell provide exchange and storage places for gas, and the hydrophobic structure layer can withstand high pressure underwater; the preparation process and hydrophobic process of the structure are low in cost and high in efficiency. The design method of the super-hydrophobic closed cabin 6 of the present invention fully considers the conditions such as temperature and water pressure, so that the size of the hydrophobic structure layer can fully meet the conditions for gas exchange, and is designed according to the size of the super-hydrophobic closed cabin 6 to meet the design requirements.

Claims

1. An underwater automatic gas capture structure, characterized in that: A super-hydrophobic closed cabin comprising a spherical structure, wherein a plurality of air holes are provided on the super-hydrophobic closed cabin, and a plurality of columns are evenly arranged on the surface of the super-hydrophobic closed cabin, wherein the columns are perpendicular to the surface of the super-hydrophobic closed cabin; The surface of the column is provided with a CNT adhesion layer, and the gaps between the columns form a hydrophobic spherical surface on the surface of the super-hydrophobic closed cabin. The hydrophobic spherical surface serves as a hydrophobic structural layer, and a stable air layer is formed in the hydrophobic structural layer. When the super-hydrophobic closed cabin is placed in water, the hydrophobic structural layer separates the surrounding liquid water from the interior of the super-hydrophobic closed cabin. When there is a partial pressure gradient between the gas partial pressure in the liquid water and the gas partial pressure in the super-hydrophobic closed chamber, the gas dissolved in the water escapes into the super-hydrophobic closed chamber, and at the same time, the mixed gas inside the super-hydrophobic closed chamber dissolves in the liquid water through the pores, completing the gas exchange; The super-hydrophobic closed chamber includes a plurality of annular support rods, which are evenly arranged from bottom to top, and the sizes of the support rods decrease from bottom to top to form the latitude of a hemispherical structure, and the support rods are connected by a plurality of curved rods, which are evenly distributed to form the warp of the hemispherical structure; and a plurality of the columns are arranged on the latitude.

2. The underwater automatic gas capture structure according to claim 1, characterized in that: The material of the CNT adhesion layer includes a mixture of polydimethylsiloxane, a curing agent and acetone, wherein the polydimethylsiloxane and the curing agent are insoluble in acetone, and the acetone solution of the polydimethylsiloxane, the curing agent and the acetone is milky white and viscous after ultrasonic dispersion; thereafter, the acetone solution is evenly covered on the surface of the column through magnetic stirring to form a hydrophobic interface CNT adhesion layer.

3. A test device for an underwater automatic gas capture structure according to any one of claims 1 to 2, characterized in that: A water tank with an upper opening is provided at the bottom of the water tank, a through hole is provided above the through hole, and a super-hydrophobic closed chamber with a hemispherical structure is provided above the through hole, and the bottom of the super-hydrophobic closed chamber with the hemispherical structure is sealed with the edge of the through hole; A gas concentration sensor is arranged in the super-hydrophobic closed cabin, a gas hood is covered on the super-hydrophobic closed cabin, the upper end of the gas hood is connected to the gas pipe, and the upper end of the water tank is arranged with a water pipe.

4. The test device for underwater automatic gas capture structure according to claim 3, characterized in that: The support rod at the lowermost end of the super-hydrophobic closed chamber of the hemispherical structure is fixed on a support ring, and the support ring is sealed and connected to the edge of the through hole.

5. The test device for the underwater automatic gas capture structure according to claim 3, characterized in that: A sealing cover is provided at the lower end of the through hole, the gas concentration sensor is installed in the sealing cover, the sealing cover is connected to the lower edge of the through hole through a sealing ring, and the wire of the gas concentration sensor passes through the sealing cover and is connected to the computer.

6. A method for designing an underwater automatic gas capture structure according to any one of claims 1 to 2, characterized in that: The following steps are involved: S1: Calculate the design underwater depth of the super-hydrophobic closed cabin H Hydrostatic pressure : in, P 1 is the normal pressure of the super hydrophobic closed cabin, ρ is the density of water, g is the acceleration due to gravity; S2: Establish the ideal gas equation for a super-hydrophobic closed chamber: in, V 1 is the volume of the air layer at normal pressure, V 2 is the volume of the air layer under hydrostatic pressure, T 1 is the temperature of the super hydrophobic closed cabin at normal pressure, T 2 is the temperature under hydrostatic pressure in the superhydrophobic closed cabin; S3: Using the Ideal Gas Equation and Hydrostatic Pressure Formula to calculate the volume of a superhydrophobic closed chamber under hydrostatic pressure V 2: S4: According to the volume formula of a sphere , calculate the radius of the air layer under hydrostatic pressure : in, R 1 is the radius of the air layer at normal pressure; S5: Super hydrophobic closed chamber descends to H When the depth increases, the air layer on the surface is squeezed, and the thickness of the hydrophobic structure layer decreases. R satisfy: in, l is the thickness of the hydrophobic structure layer; S6: Further obtain: S7: Establish the design radius of the superhydrophobic closed compartment R 0. The radius of the air layer at normal pressure R 1 and the thickness of the hydrophobic structure layer l The relationship is: S8: Combining the relationship in step S7 and step S6, we get: S9: According to the experimental environment, the room temperature and water temperature are equal, that is, , the thickness of the hydrophobic structure layer under experimental conditions is obtained l Calculation method, thickness l This is the length of the cylinder: 。

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