Flexible heat insulation soft sheet type small water body temperature gradient experiment device and experiment method thereof

Abstract

The invention belongs to the field of experimental devices, and discloses a flexible heat insulation soft sheet type small water body temperature gradient experimental device and an experimental method.The experimental device comprises a water tank, the water tank has the length direction, the water tank extends in the length direction, an in-tank cavity is formed in the water tank, and the in-tank cavity is matched with the water tank; a heating unit and a refrigerating unit are arranged outside the two ends of the water tank respectively, and the heating unit and the refrigerating unit are started at the same time so as to heat and refrigerate water in the inner cavity of the water tank at the same time; a plurality of flexible heat insulation soft pieces are arranged in the in-groove cavity, the flexible heat insulation soft pieces are arranged in the in-groove cavity at equal intervals in the length direction, and a gap exists between the lower surface of each flexible heat insulation soft piece and the bottom of the in-groove cavity. The device is suitable for a small-size water body environment, the heating unit and the refrigerating unit provide a stable heating end and a stable cooling end at the same time, water temperature gradient and temperature constant boundary conditions are formed, hot water and cold water convection is achieved through the flexible heat insulation film and the gap, and the gap also gives consideration to water body communication and tested organism passing.

Description

Technical Field

[0001] This invention belongs to the field of experimental apparatus, specifically relating to an experimental apparatus and method for a temperature gradient experiment in a small body of water using a flexible, heat-insulating sheet. Background Technology

[0002] In aquatic biological experimental research, it is often necessary to construct different water temperature environments under controlled conditions to study the organisms' temperature preferences, tolerance, and related physiological and behavioral responses. Under existing experimental conditions, constant temperature water tanks, multiple water tanks arranged side by side, or heating and cooling devices are often installed at both ends of a single water tank to achieve water temperature differences.

[0003] However, under indoor experimental conditions, the volume of the water tank is usually limited by laboratory space, equipment conditions, and the size of the experimental objects, resulting in a small-volume water environment. Under these conditions, if heating and cooling units are only installed at both ends of the water tank, the water temperature in the middle of the tank will tend to become uniform in a short time due to the rapid natural convection and heat conduction rate within the water. Only small local high-temperature or low-temperature zones will form near the heating or cooling ends, making it difficult to form a continuous and stable water temperature gradient along the overall length of the water tank.

[0004] To overcome these problems, existing technologies typically rely on significantly increasing the water volume or employing high-power heating and cooling equipment to slow down the heat exchange process. For example, in large-volume water environments, such as aquaculture ponds, the water volume is usually measured in meters, reaching tens to hundreds of cubic meters. Taking an aquaculture pond with dimensions of approximately 10 m × 5 m × 2 m (about 100 m³) as an example, in such large-volume water bodies, even with continuous heating at one end using underfloor heating or other heating devices while leaving the other end unheated, a temperature difference of only about 2–5 °C may still form inside the water. This type of temperature difference relies on the thermal inertia resulting from the extremely large water volume and is not suitable for laboratory-scale water conditions.

[0005] However, the above-mentioned schemes not only have extremely high requirements for site, energy consumption and equipment conditions, but also make it difficult to achieve a precise and controllable temperature gradient distribution, which has obvious limitations for biological experiments that need to be carried out in a limited space.

[0006] Furthermore, existing multi-temperature zone tanks or gradient devices typically use rigid partitions to separate different temperature zones. This structure not only completely blocks the flow and exchange of water between zones, easily leading to insufficient dissolved oxygen and accumulation of metabolic products, but also restricts the autonomous movement of test organisms between different temperature zones. Especially when the test organisms are large, rigid partitions can easily interfere with their behavior and even pose a risk of physical damage, making it difficult to simultaneously meet the experimental requirements of water temperature gradient control, water exchange, and free movement of test organisms. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a flexible, heat-insulating, sheet-type experimental device and method for small water body temperature gradients. The aim is to effectively slow down the rapid heat exchange in the water body through structural design, thereby constructing a stable water temperature gradient without requiring a water body of hundreds of cubic meters or high-power temperature control equipment, while also taking into account water connectivity and the mobility of the tested organisms.

[0008] To achieve the above objectives, the present invention provides the following technical solution: A flexible, heat-insulating, sheet-type small water body temperature gradient experimental device is provided, including a water tank having a length direction, the water tank extending along the length direction, the water tank having an inner cavity that matches the water tank, and external heating and cooling units respectively installed at both ends of the water tank, and the heating and cooling units being turned on simultaneously to heat and cool the water in the inner cavity of the water tank at the same time. Multiple flexible heat insulation sheets are arranged in the inner cavity of the tank, and the multiple flexible heat insulation sheets are arranged at equal intervals along the length direction in the inner cavity of the tank, and there is a gap between the lower surface of each flexible heat insulation sheet and the bottom of the inner cavity of the tank.

[0009] Preferably, the water tank has a long strip-shaped structure.

[0010] Preferably, the heating unit and the cooling unit simultaneously provide a stable heating end and a cooling end for the inner cavity of the tank, providing constant temperature boundary conditions for the formation of a water temperature gradient in the inner cavity of the tank.

[0011] Preferably, the upper ends of the multiple flexible heat-insulating sheets are suspended from the top of the water tank, and the bottom of each flexible heat-insulating sheet extends into the inner cavity of the tank.

[0012] Preferably, a crossbar is placed on the outer top of the water tank, and the crossbar extends in a direction perpendicular to the length direction. The top of the flexible heat insulation sheet has a collar, which is fitted onto the crossbar, and the flexible heat insulation sheet extends vertically downward.

[0013] Preferably, the flexible heat insulation sheet is a rubber sheet, and the length, width and height of the rubber sheet are 200mm*100mm*1.5mm.

[0014] Preferably, the spacing between any two adjacent flexible thermal insulation sheets is 5-10 cm.

[0015] Preferably, the heating unit is a heating water bath circulator, and the cooling unit is an ultra-low temperature cooling water bath circulator.

[0016] Preferably, the experimental apparatus further includes an oxygenation unit, one end of which extends into the inner cavity of the tank to supply oxygen to the water.

[0017] Preferably, the oxygenation unit comprises an air pump, an air guide pipe, and an air stone. The air pump is located outside the water tank, one end of the air guide pipe is connected to the air outlet of the air pump, and the other end of the air guide pipe is fitted with an air stone, which is placed inside the tank cavity.

[0018] Preferably, the gap is 20-25 mm. More specifically, the gap is 20 mm.

[0019] The experimental method for this experimental setup is as follows: The first step is to simultaneously start the heating and cooling devices to heat the water at one end of the tank chamber and cool the water at the other end of the tank chamber at the same time, so that the water at one end of the tank chamber is used as the heating water and the water at the other end of the chamber is used as the cooling water, and the water in the middle of the tank chamber is used as the original water. The second step involves the heating and cooling units operating continuously. Under the combined effect of the flexible insulation sheet and the lower connecting gap, the heated water, cooling water, and original water in the tank chamber undergo slow water flow and heat transfer. As the water density decreases after being heated and tends to float, and increases after being cooled and tends to sink, the water in the tank chamber inevitably experiences a predetermined degree of convection and local temperature differences during operation, thereby gradually establishing a water temperature distribution difference along the overall length of the tank chamber. The third step involves the continuous operation of the heating and cooling units, which gradually form an overall water temperature gradient distribution transitioning from the heating end to the cooling end within the tank cavity. This gradient then stabilizes after a predetermined running time, thereby obtaining an exchangeable gradient water temperature environment suitable for the experiment.

[0020] Preferably, the area between each two adjacent flexible heat insulation sheets or the area between the flexible heat insulation sheet and the end of the water tank is divided into two parts vertically, namely the upper layer and the lower layer. The predetermined temperature difference range refers to the temperature difference range between the upper layer and the lower layer being 3-4℃; the predetermined time is 30-60min.

[0021] Compared with the prior art, the beneficial effects of the present invention are: 1. Because the present invention is applicable to small-volume water environments, and the heating unit and the cooling unit provide stable heating and cooling ends for the inner chamber of the tank respectively, providing constant temperature boundary conditions for the formation of water temperature gradient in the inner chamber of the tank, and by setting a flexible heat insulation sheet, and setting a gap between the flexible heat insulation sheet and the inner bottom of the inner chamber of the tank, convection of hot and cold water is formed, and the gap also takes into account water body communication and passage of test organisms.

[0022] 2. Because this invention uses a flexible heat-insulating sheet, the purpose is to effectively slow down the rapid heat exchange process inside the water body, making it possible to form a stable water temperature gradient under small-volume indoor water conditions. This avoids the technical limitations of relying solely on increasing the water volume or increasing the temperature control power to create a temperature difference. In addition, when the test organism passes through, the heat-insulating sheet can deform under external force and be pushed open. After the test organism passes through, it automatically returns to its original suspended state due to its flexibility, providing a passage for the test organism without affecting the heat insulation effect. The flexible heat-insulating sheet is suspended on the water tank to ensure the heat insulation effect while providing a passable space for the test organism, avoiding interference from rigid partitions on the behavior of the test organism. It is particularly suitable for experiments with larger aquatic organisms.

[0023] 3. The purpose of the oxygenation unit in this invention is, on the one hand, to maintain the dissolved oxygen level in the water to meet the respiratory needs of the test organisms, and on the other hand, to promote the slow exchange of water in the lower layer of the tank so that oxygen can be evenly distributed throughout the water without disrupting the established steady state of the water temperature gradient. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the experimental apparatus in this invention; Figure 2 This is a schematic diagram of the flexible heat insulation sheet installed in the water tank in the experimental device of the present invention; Figure 3 This is a schematic diagram of the experimental apparatus in the startup phase of the present invention; Figure 4 This is a schematic diagram of the experimental apparatus in the steady-state phase of the present invention; In the diagram: 1. Water tank; 101. Heating unit; 2. Cooling unit; 3. Oxygenation unit; 4. Flexible insulation sheet; 5. Crossbar; 6. Ring; 7. Test organism; 8. Detailed Implementation

[0025] To make the technical means, creative features, objectives and effects of this invention easier to understand, the following embodiments are described in detail with reference to the accompanying drawings. It should be noted that the description of these embodiments is for the purpose of helping to understand this invention, but does not constitute a limitation of this invention.

[0026] like Figure 1-4As shown, a flexible, insulated, sheet-type small-volume water temperature gradient experimental device is used. This device has a long, narrow structure (designed to create a water temperature gradient environment under indoor experimental conditions). The water tank 1 (a transparent glass tank, approximately 1500 mm long, 150 mm wide, and 300 mm high) has a length direction H, extending along this direction. The water tank 1 contains an inner chamber 101 that matches the water tank 1 (specifically, the water tank 1 extends vertically, and its inner chamber 101 extends along the same direction and is open on the upper surface of the water tank 1). Heating units 2 are externally mounted at both ends of the water tank 1 (specifically, the heating unit 2 uses a Thermo Scientific™ Sahara S21 water bath circulator, with an operating temperature range of approximately 13°C to 100°C above ambient temperature, a maximum water bath volume of 19 L, and a circulation flow rate of approximately 17 L / L). L / min, capable of operating under standard laboratory power supply conditions (115 V, 60 Hz), used to provide stable heating conditions for a small volume of water at one end of the water bath) and cooling unit 3 (specifically: cooling unit 3 uses a ThermoScientific™ A10 refrigerated water bath circulator, with an operating temperature range of –10 ℃ to 100 ℃, a maximum water bath volume of 6 L, and a cooling power of approximately 240 W, capable of operating under standard laboratory power supply conditions (230 L / min, can operate under standard laboratory power supply conditions (115 V, 60 Hz)). (V, 50Hz), used to continuously cool a small volume of water at the other end of the water tank 1 to form a stable low-temperature boundary condition. The heating unit 2 and the cooling unit 3 are turned on simultaneously to heat and cool the water in the inner chamber 101 of the tank. Specifically, the heating unit 2 heats the water in the inner chamber 101 of the tank and the cooling unit 3 cools the water in the inner chamber 101 of the tank, and the heating unit 2 and the cooling unit 3 operate simultaneously. The heating unit 2 and the cooling unit 3 provide a stable heating end and a cooling end for the inner chamber 101 of the tank at the same time, and provide a constant temperature boundary condition for the formation of a water temperature gradient in the inner chamber 101 of the tank. Multiple flexible heat-insulating sheets 5 (specifically made of rubber sheets, with a length, width, and height of 200mm*100mm*1.5mm) are installed inside the inner chamber 101 of the tank. These flexible heat-insulating sheets 5 are evenly spaced along the length direction H within the inner chamber 101 (in this embodiment, the spacing L1 is 5-10mm, and six flexible heat-insulating sheets 5 are used). A gap L2 exists between the lower surface of each flexible heat-insulating sheet 5 and the bottom of the inner chamber 101. In the example, the gap L2 is 20-25mm, and more preferably 20mm. The purpose is to obstruct the lateral flow of the upper layer of water in the tank chamber through this structure, while allowing the lower layer of water to remain connected. This enables slow water exchange, avoids the formation of stagnant areas, improves the stability of the water environment, and promotes the uniform distribution of dissolved oxygen in the water. The tank chamber 101 forms a continuous flow space due to the multiple gaps L2, allowing the low-temperature water to sink downwards under gravity and flow along the length. The flow is slow in the direction of temperature change; specifically, the upper ends of multiple flexible heat-insulating sheets 5 are suspended from the top of the water tank 1, and the bottom of each flexible heat-insulating sheet 5 extends into the inner cavity 101 of the tank; the flexible heat-insulating sheets 5 effectively slow down the rapid heat exchange process inside the water, making it possible to form a stable water temperature gradient under the condition of a small volume of water indoors, avoiding the technical limitation of only relying on increasing the water volume or increasing the temperature control power to form a temperature difference; in addition, the flexible heat-insulating sheets 5 can also deform and be pushed open under the action of external force when the test organism 8 passes through, and automatically return to the original hanging state due to their own flexibility after the test organism 8 passes through, providing a passage for the test organism 8 without affecting the heat insulation effect; the flexible heat-insulating sheets 5 are suspended on the water tank, the purpose of which is to provide a passage for the test organism 8 while ensuring the heat insulation effect, avoiding the interference of rigid partitions on the behavior of the test organism 8, which is particularly suitable for experiments on larger aquatic organisms; More specifically: A crossbar 6 is placed on the top of the water tank 1, and the crossbar 6 extends perpendicularly to the length direction H. The top of the flexible heat insulation sheet 5 has a collar 7, which is fitted onto the crossbar 6. The flexible heat insulation sheet 5 extends vertically downward (the purpose is to block the rapid lateral flow of the water in the upper layer of the tank cavity 101, thereby slowing down the rapid heat exchange in the upper layer of the water). This device has a simple structure and strong adjustability. By adjusting the number, position and spacing of the flexible heat insulation sheets 5, different water temperature gradient distributions can be obtained in the same water tank body. It has good experimental adaptability and promotion value.

[0027] The experimental apparatus also includes an oxygenation unit 4, one end of which extends into the inner chamber 101 of the tank to supply oxygen to the water. Specifically, the oxygenation unit 4 consists of an air pump, an air delivery pipe, and an air stone. The air pump is located outside the water tank 1, one end of the air delivery pipe is connected to the air outlet of the air pump, and the other end of the air delivery pipe is fitted with an air stone, which is placed inside the inner chamber 101 of the tank. When the air pump is started, it begins to generate bubbles in the water to oxygenate it and maintain the dissolved oxygen level. The oxygenation unit 4 also assists in the slow exchange of the lower water layers, aiming to ensure that oxygen is evenly transported throughout the entire water body to guarantee the oxygen consumption of the organisms.

[0028] The principle of this experimental setup is as follows: Water with higher temperatures rises primarily because heated water expands in volume, decreasing its density. In a gravitational field, fluids with lower density experience greater buoyancy, causing the hot water to rise. This principle is applied in the upper layer using flexible insulating sheets 5 to prevent rapid hot water transfer, while allowing cooling water to settle in the lower layer. As water cools, it contracts in volume, increasing its density, causing denser water to sink to the lower flow environment. At the heating end, when the upper water temperature reaches 25°C, the lower water temperature near the flexible insulating sheets 5 drops to 22°C. In the middle section, while the upper water temperature remains at 19°C, the lower water temperature reaches 16°C. Through this layered conduction method, a continuous and stable temperature gradient is formed along the length of the water tank. The temperature difference between adjacent insulating sheets in the water area is approximately 1–3°C.

[0029] The experimental method for this experimental setup is as follows: The first step is to simultaneously start the heating and cooling devices to heat the water at one end of the tank chamber and cool the water at the other end of the tank chamber at the same time, so that the water at one end of the tank chamber is used as the heating water and the water at the other end of the chamber is used as the cooling water, and the water in the middle of the tank chamber is used as the original water. The second step involves the heating and cooling units operating continuously. Under the combined effect of the flexible insulation sheet and the lower connecting gap, the heated water, cooling water, and original water in the tank chamber undergo slow water flow and heat transfer. As the water density decreases after being heated and tends to float, and increases after being cooled and tends to sink, the water in the tank chamber inevitably experiences a predetermined degree of convection and local temperature differences during operation, thereby gradually establishing a water temperature distribution difference along the overall length of the tank chamber.

[0030] The third step involves the continuous operation of the heating and cooling units, which gradually form an overall water temperature gradient distribution transitioning from the heating end to the cooling end within the tank cavity. This gradient then stabilizes after a predetermined running time, thereby obtaining an exchangeable gradient water temperature environment suitable for the experiment.

[0031] The above devices were tested at a room temperature of 15°C. The heating unit 2 was heated to a temperature of 30°C, and the cooling unit 3 was cooled to a temperature of 2°C. After testing, such as Figure 3 As shown, during the startup phase, the temperature in each region of the tank chamber 101 is 15℃ (i.e., taking the heating unit 2 as the starting point, in the direction from the heating unit 2 to the cooling unit 3, the region between the flexible heat insulation sheet 5 near the end of the water tank 1 and the end of the water tank 1 is designated as Region 1; the region between two adjacent flexible heat insulation sheets 5 is designated as Region 2, Region 3, Region 4, Region 5, and Region 6; and finally, the region between the flexible heat insulation sheet 5 near the end of the water tank 1 and the end of the water tank 1 is designated as Region 7. Furthermore, Regions 1 to 7 are vertically divided into the upper part of Region 1, the lower part of Region 1, the upper part of Region 2, the lower part of Region 2, the upper part of Region 3, the lower part of Region 3, the upper part of Region 4, the lower part of Region 4, the upper part of Region 5, the lower part of Region 5, the upper part of Region 6, the lower part of Region 6, the upper part of Region 7, and the lower part of Region 7; the specific temperatures of each region are shown in Table 1 below: Table 1 Table 1 shows the water temperature data at each measuring point, combined with... Figure 3 As shown in the initial state, during the startup phase when heating unit 2 and cooling unit 3 have not yet had a significant effect on the water, the water in tank 1 is in a uniform temperature state consistent with room temperature, and the temperature difference between different locations is negligible. There is no systematic temperature distribution change along the length direction H. The above results indicate that the initial conditions of this experiment are consistent and can be used as a baseline for the gradual establishment of the temperature gradient after the heating and cooling are turned on. This proves that the temperature gradient formed later comes from the operation of the device rather than the initial uneven water temperature or accidental environmental fluctuations.

[0032] like Figure 4 As shown, during the steady-state phase (it should be noted that, due to the time required for heat conduction, both heating unit 2 and cooling unit 3 need time to preheat; therefore, steady-state can only be achieved after 30-60 minutes of operation with both heating unit 2 and cooling unit 3 simultaneously on), the specific temperatures of each region are shown in Table 2 below: Table 2: Combining Table 2 and Figure 4 It can be seen that after the device has been running for a predetermined time, the water in the tank has formed a temperature distribution with a clear direction along its length. The water temperature changes at each measurement location tend to be gradual, and the overall temperature distribution is relatively stable, indicating that the device has the ability to construct and maintain a gradient water temperature environment under small volume water conditions.

[0033] The above embodiments are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Various modifications or variations that can be made by those skilled in the art without creative effort within the scope of the appended claims are still within the scope of protection of this patent.

Claims

1. An experimental device for temperature gradient in small bodies of water using flexible, heat-insulating sheet-type apparatus, characterized in that, The device includes a water tank having a length direction, the water tank extending along the length direction, the water tank having an inner cavity that matches the water tank, and a heating unit and a cooling unit being externally mounted at both ends of the water tank, and the heating unit and the cooling unit being turned on simultaneously to heat and cool the water in the inner cavity of the water tank. Multiple flexible heat insulation sheets are arranged in the inner cavity of the tank, and the multiple flexible heat insulation sheets are arranged at equal intervals along the length direction in the inner cavity of the tank, and there is a gap between the lower surface of each flexible heat insulation sheet and the bottom of the inner cavity of the tank.

2. The experimental device for temperature gradient in small water bodies using flexible thermal insulation sheets as described in claim 1, characterized in that: The water tank has a long, narrow structure.

3. The experimental device for temperature gradient in small water bodies using flexible thermal insulation sheets as described in claim 2, characterized in that: The heating unit and the cooling unit simultaneously provide a stable heating end and a cooling end for the inner chamber of the tank, providing constant temperature boundary conditions for the formation of a water temperature gradient in the inner chamber of the tank.

4. The experimental device for temperature gradient in small water bodies using flexible thermal insulation sheets as described in claim 3, characterized in that: The upper ends of the multiple flexible heat insulation sheets are suspended from the top of the water tank, and the bottom of each flexible heat insulation sheet extends into the inner cavity of the tank.

5. The experimental device for temperature gradient in small water bodies using flexible thermal insulation sheets as described in claim 4, characterized in that: A crossbar is placed on the top of the water tank, and the crossbar extends in a direction perpendicular to the length direction. The top of the flexible heat insulation sheet has a collar, which is fitted onto the crossbar, and the flexible heat insulation sheet extends vertically downward.

6. The experimental device for temperature gradient in small water bodies using flexible thermal insulation film as described in claim 5, characterized in that: The flexible heat insulation sheet is a rubber sheet, and the length, width and height of the rubber sheet are 200mm*100mm*1.5mm.

7. The experimental device for temperature gradient in small water bodies using flexible thermal insulation film as described in claim 6, characterized in that: The spacing between any two adjacent flexible thermal insulation sheets is 5-10cm; the gap is 20-25mm.

8. The experimental device for temperature gradient in small water bodies using flexible thermal insulation sheets as described in claim 7, characterized in that: The experimental apparatus also includes an oxygenation unit, one end of which extends into the inner cavity of the tank to supply oxygen to the water.

9. A method for testing temperature gradients in small bodies of water using flexible insulating sheets, employing the experimental apparatus described in any one of claims 1-8, characterized in that: The steps are as follows: The first step is to simultaneously start the heating and cooling devices to heat the water at one end of the tank chamber and cool the water at the other end of the tank chamber at the same time, so that the water at one end of the tank chamber is used as the heating water and the water at the other end of the chamber is used as the cooling water, and the water in the middle of the tank chamber is used as the original water. The second step involves the heating and cooling units operating continuously. Under the combined effect of the flexible insulation sheet and the lower connecting gap, the heated water, cooling water, and original water in the tank chamber undergo slow water flow and heat transfer. As the water density decreases after being heated and tends to float, and increases after being cooled and tends to sink, the water in the tank chamber inevitably experiences convection of the predetermined temperature difference and local temperature differences during operation, thereby promoting the gradual establishment of water temperature distribution differences along the overall length of the tank chamber. The third step involves the continuous operation of the heating and cooling units, which gradually form an overall water temperature gradient distribution transitioning from the heating end to the cooling end within the tank cavity. This gradient then stabilizes after a predetermined time, thereby obtaining an exchangeable gradient water temperature environment suitable for the experiment.

10. The experimental method according to claim 9, characterized in that, The area between each two adjacent flexible heat insulation sheets or the area between the flexible heat insulation sheet and the end of the water tank, and each area is divided into two vertically, namely the upper layer of the area and the lower layer of the area. The predetermined temperature difference range refers to the temperature difference range between the upper layer of the area and the lower layer of the area being 3-4℃. The scheduled time is 30-60 minutes.

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