An intelligent flow field measurement device and method based on inertial navigation

Abstract

An intelligent flow field measurement device and method based on inertial navigation belongs to the field of environmental engineering technology. It includes a shell, and a data acquisition module, a data storage module, and a power module are arranged inside the shell. The above-mentioned intelligent flow field measurement device and method based on inertial navigation can be used for flow field measurement in water treatment structures. The measurement device is placed upstream of the water body to be measured, and various motion parameters are recorded and stored. After the device is recovered, the flow field reconstruction is completed by reading the data in the data storage module, which provides an important technical basis for complex flow field measurement and analysis. The device is smart and easy to carry, and can be recycled and reused after use. It has low cost and good economy and practicality.

Description

Technical Field

[0001] The present invention belongs to the technical field of environmental engineering, and particularly relates to an intelligent flow field measurement device and method based on inertial navigation. Background Art

[0002] There are various types of water treatment structures. The commonly used structures in the water supply process include coagulation tanks, sedimentation tanks, etc., while the commonly used structures in the sewage treatment process include moving bed biofilm reactors, oxidation ditches, cyclic activated sludge technology (CAST tanks), etc. The factors affecting the treatment effect of the structures are relatively complex, including the interaction of multiple factors such as chemical agent dosing, physical and chemical factors, and microbial characteristics. However, for a fixed-volume structure aiming to achieve the best operating effect, a large number of experiments have shown that water treatment structures are very sensitive to the flow field movement. The flow field conditions directly affect the effective volume of the water treatment process, the pollutant removal effect, the operating load, etc. Therefore, how to measure the hydraulic conditions in the water treatment structure, and then conduct research and analysis on it, and finally optimize the flow field, is a key factor in the system design and operation of the water treatment structure.

[0003] However, the measurement of hydraulic conditions in water treatment structures has always been a research difficulty. The commonly used hydraulic characterization methods mainly include empirical formula fitting, fluid mechanics software simulation, and particle image velocimetry (PIV) and other technologies. Empirical formula fitting directly calculates the flow field distribution and hydraulic conditions based on the structural parameters of the structure (such as configuration parameters such as length, width, and height) and operating parameters (surface gas velocity, phase density, fluid viscosity, etc.). Fluid mechanics software (such as CFD, CFX, Fluent, etc.) simulation obtains the two-dimensional or three-dimensional movement velocities and volume fractions of each phase by setting reasonable boundary layers and mesh divisions, and thus the flow field distribution and hydraulic conditions in the reactor can be calculated. The advantage of fluid mechanics software is that it considers the geometric configuration during simulation, and has promotional value after successful modeling. However, the conclusions of empirical formula fitting and fluid mechanics software simulation usually need to be verified with actual detection results to be credible.

[0004] Common methods for actual flow field detection are Particle Image Velocimetry (PIV) and Particle Track Velocimetry (PTV). PIV / PTV indirectly measures the transient velocity distribution of the flow field by measuring the displacement of tracer particles in a short time interval. While measuring the velocity distribution of the entire flow field, the motion characteristics of particles of different sizes in the flow field can be distinguished one by one. However, PIV / PTV mainly studies microscopic flow fields (the detection area is usually less than 50 cm*50 cm), and the equipment is large and expensive. It is usually only used in laboratories and is not suitable for flow field measurement in water treatment structures in actual projects. At present, there is no cost-effective method for flow field measurement in actual water treatment structures. Summary of the invention

[0005] In view of the above problems existing in the prior art, the purpose of the present invention is to design and provide a technical solution of an intelligent flow field measurement device and method based on inertial navigation, which can be used for flow field measurement in water treatment structures. The measurement device is placed upstream of the water body to be measured, and various motion parameters are recorded and stored. After the device is recovered, the flow field reconstruction is completed by reading the data in the data storage module, providing an important technical basis for complex flow field measurement and analysis. The device is smart and easy to carry, and can be recycled and reused after use. It has low cost and good economy and practicality.

[0006] The intelligent flow field measuring device based on inertial navigation is characterized by comprising a shell, in which a data acquisition module, a data storage module and a power module which are connected to each other are arranged.

[0007] The intelligent flow field measurement device based on inertial navigation is characterized in that the shell is composed of an upper hemisphere and a lower hemisphere that are sealed together, and an airbag is wrapped on the outside of the shell. The airbag fits the shell when not inflated, and expands after inflation; a counterweight is arranged inside the shell, a water pressure depth sensor probe is arranged on the top of the shell, and a hole is left on one side of the shell for inflation of the airbag.

[0008] The intelligent flow field measuring device based on inertial navigation is characterized in that the data acquisition module is composed of a gyroscope, an acceleration sensor, a magnetic compass, and a water pressure depth sensor connected in coordination.

[0009] The intelligent flow field measuring device based on inertial navigation is characterized in that the data storage module includes a single-chip microcomputer, a storage chip and a serial port that are connected in a coordinated manner, and the single-chip microcomputer is connected in a coordinated manner with the data acquisition module and the power module.

[0010] The intelligent flow field measurement device based on inertial navigation is characterized in that the power module includes a lithium battery, a voltage stabilizing module, a DC solenoid valve and a micro air chamber that are connected together. The power module uses a lithium battery to boost the voltage through the voltage stabilizing module to power the data storage module and the data acquisition module.

[0011] The method of the intelligent flow field measuring device based on inertial navigation is characterized by comprising the following steps:

[0012] 1) Before launching the intelligent flow field measuring device, set the start time of the floating operation through the data storage module, and fill the power module with compressed air at an air pressure of 5-10 MPa;

[0013] 2) Launch the measuring device and start measuring the flow field parameters in water;

[0014] 3) When the running time reaches the set floating operation start time, the power module is turned on and the compressed air in the power module is introduced into the airbag;

[0015] 4) After the airbag is inflated, the buoyancy will lift the device to the surface for recovery;

[0016] 5) After the device is recovered, the data is read through the data storage module to obtain accurate underwater position information, and the underwater flow field is reconstructed based on the underwater position information of the device.

[0017] The method of the intelligent flow field measuring device based on inertial navigation is characterized by comprising the following steps: the air pressure is 6-9 Mpa, preferably 7-8 Mpa.

[0018] The above-mentioned intelligent flow field measurement device and method based on inertial navigation can be used for flow field measurement in water treatment structures. The measurement device is placed upstream of the water body to be measured, and various motion parameters are recorded and stored. After the device is recovered, the flow field reconstruction is completed by reading the data in the data storage module, providing an important technical basis for complex flow field measurement and analysis. The device is smart and easy to carry, and can be recycled and reused after use. It has low cost and good economy and practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the appearance of the device structure in an embodiment of the present invention;

[0020] Figure 2 A perspective view of the device structure in an embodiment of the present invention;

[0021] Figure 3 Schematic diagram of the internal structure of the flow field measurement device;

[0022] Figure 4 This is the floating principle diagram of the flow field measurement device;

[0023] In the figure: 1 - outer shell, 11 - upper hemisphere, 12 - lower hemisphere, 13 - counterweight, 14 - water pressure depth sensor probe, 15 - airbag; 2 - data acquisition module, 21 - gyroscope, 22 - acceleration sensor, 23 - magnetic compass, 24 - water pressure depth sensor; 3 - data storage module, 31 - single-chip microcomputer, 32 - storage chip, 33 - serial port; 4 - power module, 41 - lithium battery, 42 - voltage stabilizing module, 43 - DC solenoid valve, 44 - micro air chamber. Specific implementation mode

[0024] The present invention will be further described below in conjunction with the accompanying drawings of the specification.

[0025] As shown in the figure, the intelligent flow field measurement device based on inertial navigation includes an outer shell 1, and a data acquisition module 2, a data storage module 3, and a power module 4 which are arranged inside the outer shell 1 and are cooperatively connected to each other.

[0026] Furthermore, the outer shell 1 is composed of an upper hemisphere 11 and a lower hemisphere 12 which are hermetically fitted. The upper hemisphere 11 and the lower hemisphere 12 are sealed by threads and a sealing O-ring to ensure the waterproofness of the outer shell 1. An airbag 15 is wrapped outside the outer shell 1. When not inflated, the airbag 15 fits with the outer shell 1, and when inflated, the airbag 15 expands; a counterweight 13 is arranged inside the outer shell 1, and a water pressure depth sensor probe 14 is arranged at the top of the outer shell 1, and the opening is sealed in the form of a flange or the like. A hole is left on one side of the outer shell 1 for inflating the airbag 15.

[0027] Furthermore, the data acquisition module 2 is composed of a gyroscope 21, an acceleration sensor 22, a magnetic compass 23, and a water pressure depth sensor 24 which are cooperatively connected. The water pressure depth sensor 24 is cooperatively connected with the water pressure depth sensor probe 14. The gyroscope 21 is used to obtain the rotational angular acceleration, the acceleration sensor 22 is used to obtain the linear acceleration, the magnetic compass 23 is used to obtain the real-time inclination angle and the device attitude, and the water pressure depth sensor 24 is used to obtain the water depth. Based on the integration of the angular acceleration and the linear acceleration measured by the gyroscope 21 and the acceleration sensor 22, the speed of the device during the movement can be quickly solved, and the position information during the movement can be obtained by integrating the speed. Due to the inherent physical characteristics of the gyroscope 21 and the acceleration sensor 22, the drift and noise are also integrated, resulting in the continuous accumulation and increase of errors. Therefore, additional components are further needed to correct the information obtained by the gyroscope 21 and the acceleration sensor 22. The invention uses the magnetic compass 23 to obtain the real-time inclination angle and the device attitude, and the water pressure depth sensor 24 to obtain the water depth. With the assistance of the magnetic compass 23 and the water pressure depth sensor 24, the integration error of the gyroscope 21 and the acceleration sensor 22 is eliminated, and the position information is calibrated.

[0028] Further, the data storage module 3 includes a single-chip microcomputer 31, a storage chip 32, and a serial port 33 that are cooperatively connected. The single-chip microcomputer 31 is cooperatively connected to the data acquisition module 2 and the power module 4; the single-chip microcomputer 31 is connected to the gyroscope 21, the acceleration sensor 22, the magnetic compass 23, and the water pressure depth sensor 24, and inputs the read data into the storage chip 32 for storage. The single-chip microcomputer 31 simultaneously controls the floating time in the power module 4. The data storage module 3 is used to save the measured data, and reads the data in the storage chip 32 through the serial port 33 after the operation ends.

[0029] Further, the power module 4 includes a lithium battery 41, a voltage stabilization module 42, a direct current solenoid valve 43, and a micro gas chamber 44 that are cooperatively connected. The power module 4 uses the lithium battery 41 to boost the voltage through the voltage stabilization module 42 to supply power to all devices such as the data storage module 3 and the data acquisition module 2. The lithium battery 41 supplies power to the single-chip microcomputer 31, the storage chip 32, the gyroscope 21, the acceleration sensor 22, the magnetic compass 23, the water pressure depth sensor 24, and the direct current solenoid valve 43. The micro gas chamber 44 and the airbag 15 are connected through the direct current solenoid valve 43. The direct current solenoid valve 43 is powered by direct current and uses a normally closed solenoid valve. After the power module 4 reaches the preset detection time, it provides power for the device to float upward, facilitating the recovery of the measuring device.

[0030] A method for an intelligent flow field measuring device based on inertial navigation includes the following steps:

[0031] 1) Before deploying the intelligent flow field measuring device, set the floating operation start time in the single-chip microcomputer 31 through the serial port 33, and fill the micro gas chamber 44 with compressed air. The air pressure is 5 - 10 Mpa, preferably 6 - 9 Mpa, more preferably 7 - 8 Mpa; then close the direct current solenoid valve 43, and the compressed air is stored in the micro gas chamber 44; an independent high-pressure gas cylinder can be used to inflate the micro gas chamber 44;

[0032] 2) Connect the lithium battery 41, seal the outer shell 1, and place it in the water treatment structure to be measured and record the location of the deployment site; the flow field measuring device moves in the water treatment structure under the action of water flow; the gyroscope 21, the acceleration sensor 22, the magnetic compass 23, and the water pressure depth sensor 24 respectively record the angular acceleration, linear acceleration, real-time inclination angle, and actual water depth, and record them in the storage chip 32;

[0033] 3) When the running time reaches the set floating operation start time, the normally closed direct current solenoid valve 43 is opened, connecting the micro gas chamber 44 and the airbag 15, and introducing the compressed air in the micro gas chamber 44 into the airbag 15;

[0034] 4) After the airbag 15 is inflated and expanded, it is buoyed by the buoyancy force, and the device is lifted out of the water surface for recovery;

[0035] 5) After the device is recovered, the angular acceleration and linear acceleration are read through the serial port 33, and the integral error is eliminated through the real-time inclination angle, device attitude and water depth, and the speed of the device during the movement is solved. Integrating the speed can obtain the position information during the movement; through the underwater position information of the device, the underwater flow field is reconstructed.

[0036] This device is small in size and easy to carry, and can be recycled and reused after use. It has a low cost and has good economic efficiency and practicality.

Claims

1. An intelligent flow field measurement device based on inertial navigation, characterized in that It includes a housing (1), and a data acquisition module (2), a data storage module (3), and a power module (4) which are cooperatively connected are arranged inside the housing (1); the housing (1) is composed of a upper hemisphere (11) and a lower hemisphere (12) which are hermetically cooperated, an airbag (15) is wrapped outside the housing (1), the airbag (15) fits with the housing (1) when not inflated, and the airbag (15) expands after being inflated; a counterweight (13) is arranged inside the housing (1), a water pressure depth sensor probe (14) is arranged at the top end of the housing (1), and a hole is left on one side of the housing (1) for the airbag (15) to be inflated; The data acquisition module (2) is composed of a gyroscope (21), an acceleration sensor (22), a magnetic compass (23), and a water pressure depth sensor (24) which are cooperatively connected; the data storage module (3) includes a single-chip microcomputer (31), a storage chip (32), and a serial port (33) which are cooperatively connected, and the single-chip microcomputer (31) is cooperatively connected with the data acquisition module (2) and the power module (4); the power module (4) includes a lithium battery (41), a voltage stabilizing module (42), a DC solenoid valve (43), and a micro air chamber (44) which are cooperatively connected, and the power module (4) uses the lithium battery (41) to boost the voltage through the voltage stabilizing module (42) to supply power to the data storage module (3) and the data acquisition module (2); The gyroscope is used to obtain the rotational angular acceleration, the acceleration sensor is used to obtain the linear acceleration, the magnetic compass is used to obtain the real-time inclination angle and the device attitude, and the water pressure depth sensor is used to obtain the water depth; based on the integration of the angular acceleration and the linear acceleration measured by the gyroscope and the acceleration sensor, the speed of the device during the movement is solved, and the position information during the movement is obtained by integrating the speed; The real-time inclination angle and the device attitude are obtained by using the magnetic compass, the water depth is obtained by the water pressure depth sensor, and with the assistance of the magnetic compass and the water pressure depth sensor, the integration error of the gyroscope and the acceleration sensor is eliminated, and the position information is calibrated; The measuring method of the measuring device includes the following steps: 1) Before the intelligent flow field measuring device is put into use, set the start time of the floating operation through the data storage module (3), and fill compressed air into the power module (4), and the air pressure is 5 - 10 Mpa; 2) Put the measuring device into use and start measuring the water flow field parameters; 3) When the running time reaches the set start time of the floating operation, turn on the power module (4), and introduce the compressed air in the power module (4) into the airbag (15); 4) After the airbag (15) is inflated and expanded, it is buoyed by the buoyancy force to lift the device out of the water for recovery; 5) After the device is recovered, read the data through the data storage module (3) to obtain the accurate underwater position information, and reconstruct the underwater flow field through the underwater position information of the device.

2. The intelligent flow field measurement device based on inertial navigation according to claim 1, characterized in that, In the step 1), the air pressure is 6 - 9 Mpa.

3. An intelligent flow field measurement device based on inertial navigation according to claim 2, characterized in that, The air pressure is 7 - 8 Mpa.

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