CN-121978281-A - Experimental device and method for simulating gas exchange of water-gas interface under influence of wind speed

Abstract

The experimental device and method for simulating gas exchange of a water-gas interface under the influence of wind speed are characterized by comprising an annular water tank, a wind speed simulation assembly, a gas initial concentration generation assembly and a gas concentration detection assembly, wherein the wind speed simulation assembly is arranged above the annular water tank to form an annular wind field, the gas initial concentration generation assembly comprises a water-gas mixing steel cylinder, the water-gas mixing steel cylinder is used for inputting experimental water and target gas and is connected with the annular water tank through a connecting pipeline, the gas concentration detection assembly comprises a water-gas separation unit, inert carrier gas and water samples in the annular water tank are input into the water-gas separation unit, one side of the water-gas separation unit is connected with a gas analyzer, and the gas analyzer is used for completing detection. The experimental device and the method for simulating the gas exchange of the water-gas interface under the influence of wind speed can directly, accurately and repeatedly simulate different wind speeds in a laboratory, and can synchronously, automatically and accurately monitor the gas concentration.

Inventors

• YU HAIBO
• BAI GUANGHUA
• ZHANG LIWEN
• LI XINYI
• XIAO ZHIMING
• XU ZIQI
• ZHAO QINGCHEN

Assignees

• 三峡大学

Dates

Publication Date

20260505

Application Date

20260226

Claims (10)

1. 1. The experimental device for simulating the gas exchange of a water-gas interface under the influence of wind speed is characterized by comprising an annular water tank (1), a wind speed simulation assembly (2), a gas initial concentration generation assembly (3) and a gas concentration detection assembly (4); The wind speed simulation assembly (2) is arranged above the annular water tank (1) to form an annular wind field; The gas initial concentration generating assembly (3) comprises a target gas steel bottle (15), wherein target gas is filled in the target gas steel bottle (15), the target gas steel bottle (15) is communicated with the water-gas mixing steel bottle (12) through a connecting pipeline, deionized water or experimental water is filled in the water-gas mixing steel bottle (12), and the water-gas mixing steel bottle (12) is connected with the annular water tank (1) through the connecting pipeline; The gas concentration detection assembly (4) comprises a water-gas separation unit (13), inert carrier gas and water samples in the annular water tank (1) are input into the water-gas separation unit (13), one side of the water-gas separation unit (13) is connected with a gas analyzer (17), and the gas analyzer (17) is used for completing detection.
2. 2. The experimental device for simulating the air exchange of the water-air interface under the influence of the wind speed, which is disclosed in claim 1, is characterized in that the annular water tank (1) comprises an outer annular wall (5), an inner annular wall (6) and a bottom plate (7), the outer annular wall (5), the inner annular wall (6) and the bottom plate (7) jointly enclose an annular cavity, and the annular cavity is provided with a water collecting port (9), a water return port (10), a water inlet (14) and a water outlet valve (8).
3. 3. The experimental device for simulating the gas exchange of the water-gas interface under the influence of wind speed according to claim 2, wherein the wind speed simulation assembly (2) comprises a plurality of fans which are arranged on the support frame (11) and are uniformly distributed along the central line of the annular water tank (1).
4. 4. The experimental device for simulating the gas exchange of the water-gas interface under the influence of wind speed according to claim 3 is characterized in that a wind speed sensor is arranged below the fan and above the annular water tank (1).
5. 5. The experimental device for simulating the air exchange of the water-air interface under the influence of the wind speed according to claim 3, wherein the supporting frame (11) comprises a supporting frame main body (11.1), a steering engine (11.2) is arranged in the supporting frame main body (11.1), the steering engine (11.2) drives a ball screw nut mechanism to lift up and down, the ball screw nut mechanism drives a connecting plate (11.6) to lift up and down, a plurality of groups of cantilevers (11.7) are fixed on the connecting plate (11.6), and an angle adjusting assembly is arranged at the lower end of each group of cantilevers (11.7) and fixes and adjusts the angle of the fan.
6. 6. The experimental device for simulating the air exchange of the water-air interface under the influence of wind speed according to claim 5, wherein the angle adjusting assembly comprises a U-shaped piece (11.8), an inserting rod (11.9) is fixed at the upper end of the U-shaped piece (11.8) and the inner side of a vertical part of the lower end, an inserting sleeve is fixed at the left and right sides of the lower end of a corresponding fan (2.1), the inserting rod (11.9) is inserted with the inserting sleeve and screwed into a tightening screw rod (11.10) to tightly prop up, an annular ring (11.11) is fixed at the outer side of the U-shaped piece (11.8), a positioning screw rod (11.12) is connected to the annular ring (11.11) in a threaded manner, and the positioning screw rod (11.12) is in contact with the side wall of the fan (2.1) after being screwed in.
7. 7. The experimental device for simulating the gas exchange of a water-gas interface under the influence of wind speed according to claim 2, wherein the water-gas separation unit (13) comprises a closed gas-liquid reaction chamber, a liquid inlet is arranged at the lower end of the gas-liquid reaction chamber, a gas outlet is arranged at the upper end of the gas-liquid reaction chamber, a gas guiding pipe is arranged in the gas-liquid reaction chamber, the output end of the gas guiding pipe points to the bottom in the gas-liquid reaction chamber, and the input end of the gas guiding pipe is connected with the gas inlet.
8. 8. The experimental device for simulating the gas exchange of the water-gas interface under the influence of wind speed, which is disclosed in claim 7, is characterized in that a liquid inlet of the water-gas separation unit (13) is connected with the water intake (9) through a first pipeline, a peristaltic pump (16) is further arranged on the first pipeline, an air inlet of the water-gas separation unit (13) is connected with the inert gas steel cylinder (18) through a second pipeline, and an air outlet of the water-gas separation unit (13) is connected with the gas analyzer (17) through a third pipeline.
9. 9. The experimental device for simulating the gas exchange of a water-gas interface under the influence of wind speed according to claim 8, wherein the water-gas separation unit (13) is connected with the water return port (10) through a fourth pipeline and a peristaltic pump (16).
10. 10. A method for testing an experimental set-up for simulating the exchange of water-gas interface gases under the influence of wind speed according to any one of claims 1 to 9, comprising the steps of: S1, closing a water outlet valve (8) of an annular water tank (1), acquiring a water sample containing greenhouse gases with set concentration from a gas initial concentration generation assembly (3), and injecting the water sample from the bottom of the annular water tank (1) through a water inlet (14) until a water depth value reaches an experimental set value; s2, starting a gas concentration detection assembly (4), starting a peristaltic pump (16), and adjusting the inlet air flow and the inlet water flow of the water-gas separation unit (13) to the working set values; s3, starting a data acquisition system, and recording the initial water body temperature, the ambient air pressure, the air temperature and the concentration value of CO 2 、CH 4 in the background atmosphere; s4, starting an industrial fan of the wind speed simulation assembly (2) through a central controller, adjusting the frequency of a frequency converter, observing the reading of a wind speed sensor to enable the wind speed of the water surface to reach and be stabilized at an experimental set value, and recording the wind speed as an initial time of the experiment after the wind speed is uniform and stable; S5, after the experiment is started, the gas analyzer (17) starts to continuously and real-timely detect the concentration of CO 2 、CH 4 in water, and the central controller synchronously records the data change; S6, stopping data monitoring and recording when the concentration of CO 2 、CH 4 in the water reaches a certain set value, closing a fan, a peristaltic pump (16) and a gas analyzer (17), opening a water outlet valve (8), evacuating the water in the water tank, and ending one-time test; and S7, changing the wind speed setting, and repeating the steps S4-S6 to obtain the gas exchange rate data under a plurality of groups of wind speeds.

Description

Experimental device and method for simulating gas exchange of water-gas interface under influence of wind speed Technical Field The invention relates to the technical field of environmental simulation and measurement, in particular to an experimental device and method for simulating water-gas interface gas exchange under the influence of wind speed. Background The water-gas interface exchange coefficient is the key to calculate the greenhouse gas diffusion release flux, while wind speed is generally considered to be an important factor affecting its size. In many research fields such as climate change, environmental science and engineering, hydraulic engineering, environmental impact assessment and the like, scientific researchers often need to simulate the turbulence of a water body corresponding to a specific wind speed in a laboratory environment so as to deeply examine the influence of a water-air interface exchange coefficient in the research field. In the prior art, the common physical entity experimental mode of turbulence is mainly two types, namely a field in-situ observation method, direct measurement in a naturally-occurring turbulence environment and laboratory physical simulation, wherein the conditions of turbulence are physically reproduced in a laboratory by manufacturing waves, shear flows and the like in a controlled environment such as a circulating water tank or a wind tunnel and the like, so that how a specific turbulence structure influences gas transmission is directly researched. However, the above existing methods have obvious defects, and are difficult to meet the requirements of laboratories on fine experiments. Firstly, the existing device is severely interfered by the outside, parameters such as natural wind speed, temperature, background concentration and the like are difficult to accurately control, the experimental repeatability is low, the data acquisition period is long, the cost is high, and the efficiency is low depending on weather and field conditions. Part of the devices can not directly drive by wind through indirect simulation of the influence of wind, the process is inevitably deviated, and the reliability and the accuracy of experimental results are seriously influenced. Secondly, the existing device mostly contains a plurality of independent subsystems, is respectively responsible for wave making, sampling, analysis and the like, has a complex structure, often needs frequent operation and cooperation of operators, has higher requirements on the operators, and is difficult to popularize and apply. In addition, the data acquisition of the existing device mostly adopts manual interval sampling, and the sampling behavior itself can also disturb an experimental system under the condition of no real-time property. The disconnection of the monitoring system from the analog system creates problems with the time synchronization and spatial matching of the data. Disclosure of Invention The invention aims to solve the technical problem of providing the experimental device and the method for simulating the air exchange of the water-air interface under the influence of wind speed, which can automatically maintain the uniformity and stability of the water surface, ensure the stability of the experimental environment, can programmably adjust the wind speed and the initial air concentration according to the experimental requirement, and can simulate the turbulence of the water body under different wind speeds. In order to solve the technical problems, the invention adopts the following technical scheme: An experimental device for simulating gas exchange of a water-gas interface under the influence of wind speed comprises an annular water tank, a wind speed simulation assembly, a gas initial concentration generation assembly and a gas concentration detection assembly; The wind speed simulation assembly is arranged above the annular water tank to form an annular wind field; The gas initial concentration generating assembly comprises a target gas steel cylinder, wherein target gas is filled in the target gas steel cylinder, and the target gas steel cylinder is communicated with the water-gas mixing steel cylinder through a connecting pipeline; the gas concentration detection assembly comprises a water-gas separation unit, inert carrier gas and a water sample in an annular water tank are input into the water-gas separation unit, one side of the water-gas separation unit is connected with a gas analyzer, and the gas analyzer completes detection. The annular water tank comprises an outer annular wall, an inner annular wall and a bottom plate, wherein the outer annular wall, the inner annular wall and the bottom plate jointly enclose an annular cavity, and the annular cavity is provided with a water collecting port, a water return port, a water inlet and a water outlet valve. The wind speed simulation assembly comprises a plurality of fans, and the fans are arranged on the support frame