CN116856369A - Anti-fouling diffusion method and system based on bubble curtain array - Google Patents
Anti-fouling diffusion method and system based on bubble curtain array Download PDFInfo
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- E—FIXED CONSTRUCTIONS
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- E02B15/00—Cleaning or keeping clear the surface of open water; Apparatus therefor
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Abstract
The application relates to the technical field of environmental protection dredging, in particular to an anti-fouling diffusion method and system based on a bubble curtain array. The control of the sediment leakage concentration is realized through the bubble curtain array, the depth of a field water area, the along-flow diffusion speed of sediment on the surface of a water body and the muddy water sediment concentration are obtained, the single wide air supply quantity of a first row of bubble curtains is determined according to the on-site water depth and the along-flow diffusion speed of sediment on the surface of the water body, the single wide air supply quantity of the bubble curtains and the muddy water sediment concentration are calculated according to the along-flow diffusion of the sediment concentration under the action of the bubble curtains, the sediment leakage concentration of the next row of bubble curtains is determined according to whether the sediment leakage concentration of the next row of bubble curtains exceeds a set threshold value, if the sediment leakage concentration exceeds the set threshold value, the row of bubble curtains are opened, and the concentration of the third row of bubble curtains is redetermined until the sediment leakage concentration meets the requirement, and the air supply quantity and the opening quantity of the bubble curtains are reasonably set according to the on-site condition of dredging engineering, so that sediment leakage is effectively prevented.
Description
Technical Field
The application relates to the technical field of environmental protection dredging, in particular to an anti-fouling diffusion method and an anti-fouling diffusion system.
Background
The dredging is to adopt machinery, water power and manpower to carry out underwater earth and stone excavation construction, however, the dredging process can cause suspension and diffusion of fine particle sediment, in order to prevent the diffusion pollution, the basic measure is to arrange an anti-fouling curtain outside a dredging construction area, if a ship such as a dredger enters and exits the dredging construction area, the anti-fouling curtain needs to be frequently moved, the other measure is to place a bubble curtain, and the bubble curtain has the advantage of not obstructing the normal movement of the ship compared with the anti-fouling curtain.
The bubble curtain is an upward plume formed by bubbles generated by the perforated pipe on the bottom bed driving the water body. The plume forms horizontal reflux near the water surface, and the muddy water returns to the muddy water area under the action of the horizontal reflux, so that the suspended dredging sediment is limited in the dredging area, and sediment diffusion pollution is prevented. The bubble curtain belongs to the non-physical barrier, and because of the unreasonable reason of bubble curtain air supply setting, often lead to the bubble curtain to prevent the diffusion of silt granule completely, when the bubble curtain air supply is too little, still have partial silt granule to pass upward plume diffusion, cause water pollution, unable effective control granule silt reveal diffusion, when the bubble curtain air supply is too big, the long-time high-load work of bubble curtain fan neither safety has also caused the energy extravagant.
Disclosure of Invention
The application provides an anti-fouling diffusion method and system based on a bubble curtain array, which are used for solving the problem that a bubble curtain cannot effectively prevent sediment leakage in the existing dredging engineering.
In order to achieve the above object, the present application is realized by the following technical scheme:
the application provides an anti-fouling diffusion method for a disturbance substance, which comprises a bubble curtain array, wherein the bubble curtain array comprises a plurality of columns of perforated pipes which are arranged in parallel, and the method comprises the following steps:
step 1: acquiring the depth h of a field water area and the diffusion speed u of sediment along with flow on the surface of the water body m Concentration of muddy water sediment c m ；
Step 2: h and u obtained according to step 1 m Determining single wide air supply quantity of the nth row bubble curtainn＝1,2,3……,n max ；
Step 3: according to the obtained h,And c m The sediment leakage concentration c of the position of the (n+1) th row of bubble curtain is determined by combining sediment concentration along with flow diffusion calculation under the action of the bubble curtain;
step 4: judging whether c of the position of the n+1th row bubble curtain exceeds a set threshold, and if so, starting the n+1th row bubble curtain;
and 5, repeating the methods from the step 2 to the step 4, calculating the c value of the position of each subsequent column of bubble curtain according to the determined data of each bubble curtain until the c value meets the requirement of a set threshold value, and finishing the antifouling diffusion setting of the bubble curtain array.
Through the design, the single wide air supply quantity of the bubble curtain and the number of the bubble curtains are determined through the water depth, the muddy water concentration and the muddy water along with the flow diffusion speed of the dredging engineering site, so that the pollution to the environment caused by the dredging engineering is reduced, and meanwhile, the purposes of energy conservation and emission reduction are achieved on the premise of controlling the particle sediment diffusion pollution.
Further, in step 2, the bubble curtain single wide air supply amountObtained by the following formula:
wherein g represents gravitational acceleration; h is a atm Is a standard atmospheric head.
Further, the calculation of the sediment concentration along with the flow diffusion comprises the following steps:
step 3.1: single wide air supply according to h and n columns of bubble curtainBy means of bubble plume calculation, the vertical time average speed +.>Standard deviation sigma of vertical velocity distribution and turbulent viscosity coefficient mu t ；
Step 3.2: according toCombining a flow velocity calculation formula of any point of the bubble curtain horizontal flow to determine the surface layer horizontal flow velocity u;
step 3.3: according to c m 、And u binds sigma and mu t And confirming the c of the n+1th column bubble curtain position according to a calculation formula of the stable concentration of the sediment particles along with the flow diffusion.
Further, in the step 3.1, the bubble plume calculation specifically includes:
the single wide air supply quantity of the bubble curtain according to h and n columns is calculated by the bubble plumeDetermining +.f. by using a dimensionless plume momentum equation and a dimensionless kinetic energy equation and combining a turbulent viscosity coefficient calculation formula>Sigma and mu t ；
The dimensionless momentum equation is:
wherein k is the ratio of the vertical component of the pulsation kinetic energy of the bubble plume flow point to the vertical component of the time-averaged kinetic energy;
λ is the ratio of the standard deviation of the time-averaged velocity distribution to the standard deviation of the time-averaged mass distribution of the bubble plume;
the v, ζ and ζ are non-dimensional parameters;
the dimensionless parameter v expression is:
wherein Δw is the bubble slip velocity relative to the plume;
the dimensionless parameter ζ expression is:
ζ＝z/h * ；
wherein z represents the water depth;
h * is a standard atmospheric pressure water head h atm And the sum of the water depth h of the site;
the dimensionless parameter xi expression is:
the bubble plume flow energy equation is:
wherein G is expressed as:
wherein I is an empirical constant term;
the calculation formula of the turbulence viscosity coefficient is as follows:
where w is expressed as the mean value of the vertical flow velocity component and satisfies
Further, k, λ and Δw are all empirical parameters, where the k takes a value ranging from 0.28 to 0.32, λ takes a value ranging from 0.475 to 0.525, Δw takes a value ranging from 0.28m/s to 0.32m/s, and the empirical value constant term I takes a value ranging from 0.12 to 0.14.
Further, in step 3.2, the flow velocity calculation formula at any point of the horizontal flow of the bubble curtain is:
wherein x is the distance from any point of the surface horizontal flow to the bubble curtain, z is the height from any point of the surface horizontal flow to the water bottom, u max Is the maximum horizontal flow speed of the surface layer;
the maximum horizontal flow velocity u of the surface layer max The expression is:
further, in step 3.3, the position c of the n+1th column bubble curtain is confirmed by the following method:
wherein c is the leakage concentration of sediment;
m is the line source intensity per unit length calculated with the horizontal flow diffusion concentration, m=f s F t (c 0 )；
Wherein the source concentration is calculated as the horizontal flow diffusion concentration
D th Is the turbulent diffusion coefficient in the horizontal flow,
u is the average flow velocity in the horizontal flow,
in the above formula:
in the above formula, m' is the line source intensity per unit length calculated along with the diffusion concentration of the bubble plume;
D tv for the turbulent diffusion coefficient in the plume,
w is the vertical average velocity of the bubble plume,
the unit length source intensity m' calculated with the bubble plume diffusion concentration is expressed as follows:
m′＝F s F t (c m )；
wherein F is t Is a fourier transform in time;
F s is a spatial fourier transform.
Further, in step 1, the h is obtained by a depth finder, and the u is m By recording the time of passage of muddy water past adjacent immobilized markers, said c m Obtained by a turbidimeter.
Further, adjacent single-row bubble curtains are spaced from each other by 5-7 times the depth h of the field water.
In a second aspect, the application provides an anti-fouling diffusion system based on a bubble curtain array, which comprises a measuring device, a control device and the bubble curtain array, wherein the control device comprises a data storage module and a data processing module, and the data storage module stores a processing program corresponding to a single wide air supply amount calculation formula of the bubble curtain, a calculation formula of a flow velocity of any point of a horizontal flow of the bubble curtain, and a calculation formula of a stable concentration of sediment particles along with flow diffusion:
the measuring device is used for measuring the depth h of the on-site water area and the diffusion speed u of sediment on the surface of the water body along with the flow m Concentration of muddy water sediment c m And transmitting to the control device;
the control device is used for receiving the depth h of the on-site water area and the diffusion speed u of sediment on the surface of the water body along with the flow m Concentration of muddy water sediment c m Acquiring the single-width air supply quantity of the bubble curtain by combining the data processing module with the processing program stored in the data storage moduleThe action information corresponding to the opening quantity of the bubble curtains is transmitted to the bubble curtain array;
the air bubbleA curtain array for receiving a single wide air supply of the bubble curtainAnd executing the action information corresponding to the opening quantity of the bubble curtain and executing the bubble curtain adjusting the air supply quantity of the bubble curtain and the opening quantity of the bubble curtain corresponding to the action information.
The beneficial effects are that:
according to the anti-fouling diffusion method based on the bubble curtain array, the single-width air supply quantity and the number of the bubble curtains are determined according to the water depth, the muddy water concentration and the muddy water along-flow diffusion speed of the dredging engineering site, so that pollution to the environment caused by the dredging engineering is reduced, the opening quantity and the air supply quantity of the bubble curtains can be flexibly set according to the site situation of the dredging engineering, and the purposes of energy conservation and emission reduction are achieved on the premise of guaranteeing the anti-fine particle sediment diffusion effect.
According to the anti-fouling diffusion method based on the bubble curtain array, provided by the application, the space between the bubble curtains is reasonably set in a bubble curtain array mode, so that the influence of fine particle sediment on a clean water side is reduced as much as possible, and the environment is protected.
According to the anti-fouling diffusion system based on the bubble curtain array, provided by the application, the on-site construction area of the dredging engineering is measured rapidly through the measuring device, the air supply quantity and the opening quantity of the bubble curtain are acquired rapidly and conveniently through the control device, and the pollution of fine particle sediment diffusion to the environment is reduced as much as possible.
Drawings
FIG. 1 is a schematic flow chart of an anti-fouling diffusion method based on a bubble curtain array according to a preferred embodiment of the application;
FIG. 2 is a schematic diagram showing operation of the bubble curtain array according to the preferred embodiment of the present application;
FIG. 3 is a schematic block diagram of an anti-fouling diffusion system based on a bubble curtain array according to a preferred embodiment of the present application.
Detailed Description
The following description of the present application will be made clearly and fully, and it is apparent that the embodiments described are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this application belongs. The terms "first," "second," and the like, as used herein, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. Likewise, the terms "a" or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", etc. are used merely to indicate a relative positional relationship, which changes accordingly when the absolute position of the object to be described changes.
Example 1
Referring to fig. 1-2, an embodiment of the present application provides an anti-fouling diffusion method based on a bubble curtain array, and the control of the silt leakage concentration is achieved through the bubble curtain array.
Step 1: acquiring the depth h of a field water area and the diffusion speed u of sediment along with flow on the surface of the water body m Concentration of muddy water sediment c m 。
In implementation, the depth h of the water area is obtained by a depth finder, and the diffusion speed v of sediment on the surface of the water body along with the flow m By recording the time taken for the muddy water to pass adjacent fixed markers, the muddy water sediment concentration c m Obtained by a turbidimeter.
The bubble curtain array is formed by arranging a plurality of rows of perforated pipes in parallel, and the distance between the perforated pipes is 5-7 times of the depth h of the on-site water area.
Step 2: according to the obtained on-site water depth h and the along-flow diffusion speed u of sediment on the surface of the water body m Determining single wide air supply quantity of first row bubble curtain
In practice, the first bubble curtain is single wide in air supplyObtained by a derivation formula of a calculation formula of the maximum horizontal flow velocity of the bubble curtain.
The maximum horizontal flow rate calculation formula of the bubble curtain is as follows:
wherein u is max Is the diffusion speed of sediment along with the flow on the surface of the water body.
g is gravitational acceleration.
h atm Is a standard atmospheric head.
h is the water depth of the site.
The formula is deformed to obtain a single wide air supply quantity calculation formula of the bubble curtain:
step 3: according to h,And c m And (3) calculating along with the flow diffusion of the sediment concentration under the action of the bubble curtain, and determining the sediment leakage concentration c of the position of the next column of bubble curtain.
When the sediment concentration along with the flow diffusion calculation is carried out, the method comprises the following steps:
step 3.1: according to h and the single wide air supply quantity of the first row of bubble curtainBy means of bubble plume calculation, the vertical time average speed +.>Standard deviation sigma of vertical velocity distribution and turbulent viscosity coefficient mu t 。
Wherein, bubble plume calculation specifically includes:
calculation of bubble plume according to water depth h and single wide air supply of bubble curtainDetermining and acquiring the vertical time average speed w at the center of the bubble plume by combining a dimensionless plume momentum equation and a dimensionless kinetic energy equation and a turbulent viscosity coefficient calculation formula c Standard deviation sigma of vertical velocity distribution and turbulent viscosity coefficient mu t 。
In the vertical two-dimensional line source problem, the vertical momentum equation of the bubble plume (gas-water mixture) is:
wherein ρ is the density of the gas-water mixture, ρ w Is the density of water ρ a For air density, u and w are the horizontal and vertical components of plume flow velocity, m is the mass of the bubble in the unit volume of water, g is gravitational acceleration, p d Is the difference between the total pressure p and the hydrostatic pressure.
p d ＝p-p w g(h-z)； (2)
Homogenizing of formula (1) while ρ w Instead of p,
in the above-mentioned method, the step of,and->For the horizontal and vertical flow component time average, u 'and w' are the flow horizontal and vertical component pulsation values.
Neglecting the pressure difference p d Vertical integration is performed from the water bottom to the height z in the formula (3), and horizontal integration is performed from- + -infinity to obtain:
in the integration, the velocity is zero in the horizontal direction ±infinity.
Assume that w and m obey a gaussian distribution in the horizontal direction, i.e.:
in the above-mentioned method, the step of,and m c The average velocity and the average bubble mass mean value at the center of the bubble plume are expressed, sigma is the standard deviation of the vertical velocity distribution, and lambda is the ratio of the standard deviation of the average velocity distribution and the standard deviation of the uniform mass distribution of the bubble plume.
Assume again that:
where k is the ratio of the vertical component of the pulsation kinetic energy of the bubble plume flow particle to the vertical component of the time-averaged kinetic energy.
Further, it is assumed that thermal expansion such as bubble rising process is performed:
in the above, h atm Is a standard atmospheric pressure water head,is the air density at standard atmospheric pressure.
Substituting the formulas (6) and (7) into the formula (4) to obtain:
in the formula, h * ＝h atm +h。
Horizontal section bubble mass flow:
where Δw is the bubble slip velocity, i.e., velocity relative to the plume.
Substituting formula (5) into formula (9) to obtain:
substituting formula (10) into formula (8) to obtain:
equation (11) is referred to as the bubble plume momentum equation, wherein,neglecting the pressure term in equation (3), the two sides of the equation are multiplied by w at the same time to obtain:
also, spatially integrating equation (12) yields:
assuming that the bubble plume belongs to a self-modal flow, there are:
where the parameter η=x/σ (z).
Substituting formulas (5), (7), (10) and (14) into formula (13) to obtain:
equation (15) is referred to as the bubble plume flow energy equation, in which,
defining dimensionless parameters:
the dimensionless forms of the bubble plume momentum and kinetic energy equations are respectively:
in the method, in the process of the application,
at the location of the gas source,
in the above formula, the subscript 0 represents a gas source.
In the calculation, the ratio k of the vertical component of the pulse kinetic energy of the flow particles of the bubble plume to the time-averaged kinetic energy, the ratio lambda of the velocity distribution of the flow particles of the bubble plume to the standard deviation of the mass distribution, and the slip velocity Deltaw of the bubble with respect to the plume are all empirical parameters, wherein the value of the empirical value constant term k is 0.3, the value of the ratio lambda of the velocity distribution of the flow particles of the plume to the standard deviation of the mass distribution is 0.5, the value of the slip velocity Deltaw of the bubble with respect to the plume is 0.3m/s, the value of the empirical value constant term I is 0.13, G, v and xi are obtained by the formulae (20), (18) and (19), respectively, and finally w is obtained by the formula (17) c And sigma.
According to formula (6), there are:
turbulence viscosity coefficient mu t The method comprises the following steps:
step 3.2: according toAnd determining the surface level flow velocity u by combining a flow velocity calculation formula of any point of the bubble curtain horizontal flow.
After the bubble plume reaches the water surface, the bubble plume deflects to form a surface layer horizontal flow. According to the experimental results of Bulson (1963), in shallow water, the horizontal flow thickness is about 0.28h, and the maximum surface flow rate of the horizontal flow is:
the horizontal flow ranges from 6 times the depth of water.
Assuming that the horizontal velocity in the horizontal flow decreases linearly along the depth to zero, the surface horizontal flow rate decreases linearly from the centerline position of the bubble curtain to zero after a 6-fold depth distance.
The speed at any point in the horizontal flow is:
step 3.3: according to c m 、u binds sigma and mu t And confirming the position c of the second row of bubble curtain according to a calculation formula of the stable concentration of the sediment particles along with the flow diffusion.
The sediment particles can be divided into two parts in the bubble curtain diffusion process, firstly, the sediment particles enter a clean water side through turbulent diffusion and enter a horizontal flow layer upwards under the action of bubble plumes; and secondly, the sediment particles are diffused along with the flow under the action of the horizontal flow layer.
(a) Along with the diffusion of the bubble plume:
this process can be seen as a time-continuous stable line source single-sided current-following diffusion problem.
The concentration c' along-with-flow diffusion equation for this process is:
wherein D is tv W is the vertical average velocity of the bubble plume, which is the turbulence diffusion coefficient in the plume.
For the continuous stable point source problem of two-dimensional diffusion in a uniform flow, the steady state concentration at any position is:
where M is the point source intensity.
For a stable line source with a water depth of 0.72 times, the steady state concentration at any position is:
where m' is the line source intensity per unit height calculated with the bubble plume diffusion concentration.
The relation between the source sediment concentration and the unit length line source intensity is:
c m ＝m′δ(x)δ(t)； (29)
where δ (x) and δ (t) are dirac functions.
Therefore:
m′＝F s F t (c m )； (30)
wherein F is t Is a fourier transform in time;
F s is a spatial fourier transform;
w takes the average of the vertical velocities in the plume range, namely:
D tv taking an average value of turbulence viscosity coefficients in the plume range, namely:
(b) Diffusion with flow in horizontal flow:
this process can be seen as a problem of spreading with the flow over a limited width of the time-continuous stable line source.
According to the horizontal flow model, the water flow width is 0.28 times of the water depth.
The process concentration c along with the flow diffusion equation is:
wherein D is th The diffusion coefficient is the turbulence diffusion coefficient in the horizontal flow, and U is the average flow velocity in the horizontal flow.
Under the conditions of uniform flow and continuous stable point source, the steady state concentration at any position is as follows:
for a line source of sigma (0.72 h) length, the steady state concentration at any position is:
wherein m is the line source strength per unit length calculated according to the horizontal flow diffusion concentration, and comprises:
m＝F s F t (c 0 )； (36)
wherein, c 0 For the source concentration calculated as the horizontal flow diffusion concentration, the concentration average value in the plume range of 0.72 times the water depth is taken, namely:
D th taking the average value of turbulence viscosity coefficients in the plume range with the water depth of 0.72 times, namely:
average flow rate in U horizontal flow, namely:
step 4: judging whether the position c of the second row of bubble curtains exceeds a set threshold, and opening the second row of bubble curtains if the position c exceeds the set threshold.
Step 5: and (3) repeating the methods from the step (2) to the step (4), calculating the c value of the position of each subsequent row of bubble curtain according to the determined data of each bubble curtain until the c value meets the requirement of a set threshold value, and finishing the antifouling diffusion setting of the bubble curtain array.
The single-width air supply quantity and the number of the bubble curtains are determined through the water depth, the muddy water concentration and the muddy water along with the flow diffusion speed of the dredging engineering site, so that the pollution to the environment caused by the dredging engineering is reduced, and meanwhile, the purposes of energy conservation and emission reduction are achieved on the premise of ensuring the four-particle sediment diffusion effect.
Example 2
Referring to fig. 3, an embodiment of the present application provides an anti-fouling diffusion system based on a bubble curtain array, which includes a measurement device, a control device and a bubble curtain array, where the control device includes a data storage module and a data processing module, and the data storage module stores a processing program corresponding to a single wide air supply amount calculation formula of the bubble curtain, a calculation formula of a flow velocity of any point of a bubble plume, a calculation formula of a horizontal flow of the bubble curtain, and a calculation of a stable concentration of sediment particles along with flow diffusion:
the measuring device is used for measuring the depth h of the on-site water area and the diffusion speed u of sediment on the surface of the water body along with the flow m Concentration of muddy water sediment c m And transmitted to the control device.
The control device is used for receiving the depth h of the on-site water area and the diffusion speed u of sediment on the surface of the water body along with the flow m Concentration of muddy water sediment c m Acquiring the single-width air supply quantity of the bubble curtain by combining a data processing module with a processing program stored in a data storage moduleAnd transmitting the action information corresponding to the opening quantity of the bubble curtain to the bubble curtain array.
A bubble curtain array for receiving single wide air supply of bubble curtainAnd executing the action information corresponding to the opening quantity of the bubble curtain and executing the bubble curtain adjusting the air supply quantity of the bubble curtain and the opening quantity of the bubble curtain corresponding to the action information.
The foregoing describes in detail preferred embodiments of the present application. It should be understood that numerous modifications and variations can be made in accordance with the concepts of the application by one of ordinary skill in the art without undue burden. Therefore, all technical solutions which can be obtained by logic analysis, reasoning or limited experiments based on the prior art by the person skilled in the art according to the inventive concept shall be within the scope of protection defined by the claims.
Claims (10)
1. An anti-fouling diffusion method based on a bubble curtain array, which is characterized by comprising a bubble curtain array, wherein the bubble curtain array comprises a plurality of bubble curtains which are arranged in parallel, and the method comprises the following steps:
step 1: acquiring the depth h of a field water area and the diffusion speed u of sediment along with flow on the surface of the water body m Concentration of muddy water sediment c m ；
Step 2: h and u obtained according to step 1 m Determining single wide air supply quantity of the nth row bubble curtain
Step 3: according to the obtained h,And c m The sediment leakage concentration c of the position of the (n+1) th row of bubble curtain is determined by combining sediment concentration along with flow diffusion calculation under the action of the bubble curtain;
step 4: judging whether c of the position of the n+1th row bubble curtain exceeds a set threshold, and if so, starting the n+1th row bubble curtain;
and 5, repeating the methods from the step 2 to the step 4, calculating the c value of the position of each subsequent column of bubble curtain according to the determined data of each bubble curtain until the c value meets the requirement of a set threshold value, and finishing the antifouling diffusion setting of the bubble curtain array.
2. The method of claim 1, wherein in step 2, the bubble curtain single width air supply is providedObtained by the following formula:
wherein g represents gravitational acceleration; h is a atm Is a standard atmospheric head.
3. The method of claim 1, wherein the calculation of the sediment concentration along with the flow diffusion comprises the steps of:
step 3.1: single wide air supply according to h and n columns of bubble curtainBy means of bubble plume calculation, the vertical time average speed +.>Standard deviation sigma of vertical velocity distribution and turbulent viscosity coefficient mu t ；
Step 3.2: according toCombining a flow velocity calculation formula of any point of the bubble curtain horizontal flow to determine the surface layer horizontal flow velocity u;
step 3.3: according to c m 、And u binds sigma and mu t And confirming the c of the n+1th column bubble curtain position according to a calculation formula of the stable concentration of the sediment particles along with the flow diffusion.
4. The method of claim 3, wherein in step 3.1, the bubble plume calculation is specifically:
the single wide air supply quantity of the bubble curtain according to h and n columns is calculated by the bubble plumeDetermining +.f. by using a dimensionless plume momentum equation and a dimensionless kinetic energy equation and combining a turbulent viscosity coefficient calculation formula>Sigma and mu t ；
The dimensionless momentum equation is:
wherein k is the ratio of the vertical component of the pulsation kinetic energy of the bubble plume flow point to the vertical component of the time-averaged kinetic energy;
λ is the ratio of the standard deviation of the time-averaged velocity distribution to the standard deviation of the time-averaged mass distribution of the bubble plume;
the v, ζ and ζ are non-dimensional parameters;
the dimensionless parameter v expression is:
wherein Δw is the bubble slip velocity relative to the plume;
the dimensionless parameter ζ expression is:
ζ＝z/h * ；
wherein z represents the water depth;
h * is a standard atmospheric pressure water head h atm And the sum of the water depth h of the site;
the dimensionless parameter xi expression is:
the bubble plume flow energy equation is:
wherein G is expressed as:
wherein I is an empirical constant term;
the calculation formula of the turbulence viscosity coefficient is as follows:
where w is expressed as the mean value of the vertical flow velocity component and satisfies
5. The method of claim 4, wherein k, λ, and Δw are empirical parameters, wherein k is in the range of 0.28-0.32, λ is in the range of 0.475-0.525, Δw is in the range of 0.28-0.32 m/s, and the empirical value constant term I is in the range of 0.12-0.14.
6. The method of claim 3, wherein in step 3.2, the flow velocity calculation formula at any point of the horizontal flow of the bubble curtain is:
wherein x is the distance from any point of the surface horizontal flow to the bubble curtain, z is the height from any point of the surface horizontal flow to the water bottom, u max Is the maximum horizontal flow speed of the surface layer;
the maximum horizontal flow velocity u of the surface layer max The expression is:
7. the method of claim 3, wherein in step 3.3, c of the n+1th column bubble curtain position is confirmed by:
wherein c is the leakage concentration of sediment;
m is the line source intensity per unit length calculated with the horizontal flow diffusion concentration, m=f s F t (c 0 )；
Wherein the source concentration is calculated as the horizontal flow diffusion concentration
D th Is the turbulent diffusion coefficient in the horizontal flow,
u is the average flow velocity in the horizontal flow,
in the above formula:
in the above formula, m' is the line source intensity per unit length calculated along with the diffusion concentration of the bubble plume;
D tv for the turbulent diffusion coefficient in the plume,
w is the vertical average velocity of the bubble plume,
the unit length source intensity m' calculated with the bubble plume diffusion concentration is expressed as follows:
m′＝F s F t (c m )；
wherein F is t Is a fourier transform in time;
F s is a spatial fourier transform.
8. The method of claim 1, wherein in step 1, the h is obtained by a depth finder, and the u is m By recording the time of passage of muddy water past adjacent immobilized markers, said c m Obtained by a turbidimeter.
9. The method of claim 1, wherein adjacent single-row bubble curtains are spaced from each other by a depth h of 5-7 times the depth of the field.
10. The utility model provides an antifouling diffusion system based on bubble curtain array, its characterized in that includes measuring device, controlling means and bubble curtain array, controlling means includes data storage module and data processing module, data storage module stores the processing procedure that bubble curtain single wide air supply volume calculation formula, bubble plume calculation, the arbitrary point velocity of flow calculation formula of bubble curtain horizontal flow and silt granule along with flowing diffusion stable concentration calculation correspond:
the measuring device is used for measuring the depth h of the on-site water area and the diffusion speed u of sediment on the surface of the water body along with the flow m Concentration of muddy water sediment c m And transmitting to the control device;
the control device is used for receiving the depth h of the on-site water area and the diffusion speed u of sediment on the surface of the water body along with the flow m Concentration of muddy water sediment c m Acquiring the single-width air supply quantity of the bubble curtain by combining the data processing module with the processing program stored in the data storage moduleThe action information corresponding to the opening quantity of the bubble curtains is transmitted to the bubble curtain array;
the bubble curtain array is used for receiving single wide air supply quantity of the bubble curtainAnd executing the action information corresponding to the opening quantity of the bubble curtain and executing the bubble curtain adjusting the air supply quantity of the bubble curtain and the opening quantity of the bubble curtain corresponding to the action information.
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