Method for determining optimal installation parameters of submersible mixer

Abstract

The invention provides a method for determining optimal installation parameters of a submersible mixer, which comprises the following steps of: installing the submersible mixer at different positions of a water pool, and calculating the average speed of fluid, the flow velocity uniformity of the fluid, the invalid mixing volume ratio and the efficient mixing volume ratio; finding out the position with the maximum slope on a curve graph through the curve graph of the installation position variable and the fluid average speed, preliminarily deducing a plurality of optimal installation positions, and determining an optimal installation position by combining the uniformity of the fluid speed and the proportion peak value of the invalid stirring volume and the efficient stirring volume; the method comprises the following steps: installing a submersible mixer at an optimal installation position, setting a plurality of horizontal inclination angles, respectively calculating the average speed of the fluid in a stirring flow field when the submersible mixer is installed at different angles, and finding out a fitting curve of the average speed of the stirring fluid and the deflection angle at different installation angles; the horizontal inclination angle corresponding to the maximum speed curve change rate in the curve is the optimal mounting angle. According to the invention, the optimal installation parameters of the submersible mixer can be quickly and conveniently found.

Description

Technical Field

[0001] The invention belongs to the field of sewage treatment hydraulic machinery, and in particular, relates to a method for determining optimal installation parameters of a submersible mixer. Background Art

[0002] Sewage mixers are new equipment widely used in urban, industrial and agricultural wastewater treatment processes. Compared with submersible mixers, mixing pools are large. The installation parameters of submersible mixers include: the x, y, z coordinates of the location of the submersible mixer and the installation angle α. At present, these installation parameters are difficult to determine, and the installation parameters are generally determined by feeling or experience in engineering. This often results in blind matching and purchasing of submersible mixers. In order to achieve a better mixing effect, the speed or power of the submersible mixer has to be increased, or the number of mixers in the pool has to be increased, and sometimes the result of "old cows pulling a big cart" occurs. These are not economically cost-effective for enterprises. How to use the least number of mixers and the submersible mixer with the minimum power to mix a relatively larger pool and obtain the best mixing effect has always been a difficult problem in the industry. How to match submersible mixers with pools has also been a problem to be solved in the industry. Summary of the invention

[0003] In response to the above technical problems, the present invention provides a method for determining the optimal installation parameters of a submersible mixer, which can quickly and conveniently find the optimal installation position and installation angle of the submersible mixer, so that the mixer has the best stirring effect, the minimum stirring dead zone in the tank, and the average stirring speed meets the stirring requirements.

[0004] The present invention achieves the above technical objectives through the following technical means.

[0005] A method for determining optimal installation parameters of a submersible mixer comprises the following steps:

[0006] Establishing 3D model: Establishing simulation 3D models of the submersible mixer and the water tank, and installing the simulation 3D model of the submersible mixer in the simulation 3D model of the water tank;

[0007] Determine the optimal installation position: When the submersible mixer simulation 3D model is installed at different positions of the water tank simulation 3D model, the stirring flow field in the stirring water tank is stirred, and the average fluid velocity, fluid velocity uniformity, invalid stirring volume ratio and efficient stirring volume ratio are calculated by software. The maximum slope of the curve of the submersible mixer installation position variable and the average fluid velocity is found, and several optimal installation positions are preliminarily inferred. Then, combined with the uniformity of the fluid velocity, the peak values ​​of the invalid stirring volume and the efficient stirring volume ratio, an optimal installation position is determined from the several optimal installation positions preliminarily inferred.

[0008] Determine the optimal installation angle: install the submersible mixer at the optimal installation position, set multiple horizontal inclination angles of the submersible mixer, calculate the average velocity of the fluid in the mixing flow field when the submersible mixer is installed at different angles, and find the horizontal inclination angle corresponding to the maximum change rate of the velocity curve in the fitting curve of the average velocity of the mixing fluid of the mixer and the deflection angle of the mixer at different installation angles as the optimal installation angle.

[0009] In the above solution, the software is CFD software.

[0010] In the above solution, the step of determining the optimal installation position is specifically as follows:

[0011] When the submersible mixer simulation three-dimensional model is installed at different positions of the water tank simulation three-dimensional model, the stirring flow field in the stirring water tank is stirred, and the software is used to calculate and draw the submersible mixer installation position variable and the fluid average velocity curve, the installation position variable and the stirring fluid flow velocity uniformity curve in the tank, the installation position variable and the ineffective stirring volume ratio curve of the stirring fluid in the tank, and the installation position variable and the efficient stirring volume ratio curve of the stirring fluid in the tank; the submersible mixer installation position variable and the fluid average velocity curve are used to find the point with the largest slope on the curve, and preliminarily infer several optimal installation positions; then combined with the installation position variable and the stirring fluid flow velocity uniformity curve in the tank, the installation position variable and the ineffective stirring volume ratio curve of the stirring fluid in the tank, and the installation position variable and the efficient stirring volume ratio curve of the stirring fluid in the tank, the uniformity of the fluid velocity, the peak value of the invalid stirring volume and the efficient stirring volume are comprehensively considered, and finally an optimal installation position is determined from the several optimal installation positions preliminarily inferred.

[0012] Furthermore, the uniformity of the comprehensive fluid velocity, the peak values ​​of the proportion of the ineffective stirring volume and the efficient stirring volume are finally used to determine an optimal installation position from several optimal installation positions preliminarily inferred, specifically: an installation position that satisfies the maximum uniformity of the fluid velocity, the maximum proportion of the efficient stirring volume, and the minimum proportion of the ineffective stirring fluid volume.

[0013] In the above solution, the step of determining the optimal installation angle is specifically as follows:

[0014] The submersible mixer is installed at the optimal installation position, and multiple horizontal inclination angles of the submersible mixer are set. The mixing flow field when the submersible mixer is installed at different angles is calculated respectively. The fitting curves of the average velocity of the mixing fluid and the deflection angle of the mixer at different installation angles are drawn, and the horizontal inclination angle corresponding to the maximum change rate of the velocity curve in the fitting curve is found. This inclination angle is the optimal installation angle.

[0015] In the above scheme, the submersible mixer simulation 3D model is installed in the pool simulation 3D model:

[0016] The center of the pool is point o, and the coordinates of point o are (0, 0, 0.5H). H is the height of the pool. The mixing shaft of the submersible mixer is parallel to the long side L of the pool, which is the x direction.

[0017] Furthermore, several sections H with different heights are selected along the height direction of the pool bottom. i , i=1,2,3……,n, n is a positive integer; cross section H i Parallel to the pool bottom, at section H i Cut several line segments L on ij , j = 1, 2, 3 ... m, m is a positive integer; in L ij Several installation positions are selected and the submersible mixers are installed at these installation positions in turn. The average fluid velocity, fluid flow rate uniformity, ineffective stirring volume proportion and efficient stirring volume proportion are calculated by software.

[0018] Furthermore, line segment L ij ,As the installation position of the submersible mixer moves along the positive direction of the Y axis, the average velocity of the fluid in the pool increases rapidly and eventually stabilizes. Assuming that Y = y i When , the slope of the curve of the installation position variable and the average velocity of the stirring fluid in the pool is the largest at this point, and the i×j optimal installation positions are preliminarily inferred.

[0019] Furthermore, the fluid flow rate uniformity, efficient stirring volume proportion, and ineffective stirring volume proportion at the i×j optimal installation positions are compared. When the mixer is installed at one of the positions, the fluid flow rate uniformity is optimal, the efficient stirring volume proportion reaches the maximum, and the ineffective stirring volume proportion is the smallest, and the stirring effect is optimal. The optimal installation position is determined to be (x, y, z).

[0020] Furthermore, at the optimal installation position (x, y, z), the installation angle α of the submersible mixer is used as variables α1, α2, ...α n , n is the number of installation angles; numerical calculations are performed for different installation angles to obtain the average flow velocity of the fluid in the mixing tank, and a curve diagram of the installation angle variable and the average flow velocity is drawn. The angle variable corresponding to the point where the velocity change curvature is the largest in the curve diagram is the optimal installation angle, and the optimal installation parameters of the submersible mixer can be obtained as (x, y, z, α).

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention can quickly and conveniently find the best installation position and installation angle of the submersible mixer, so that the mixer has the best stirring effect, the stirring dead zone in the tank is the least, and the average stirring speed meets the stirring requirements.

[0023] The present invention only needs to count the average flow rate of the stirring fluid in the pool under various installation parameters, which greatly reduces the workload of data statistics and comparison. By combining and comparing the ineffective stirring volume of the fluid in the pool under different installation parameters, the efficient stirring volume of the fluid, and the uniformity of the fluid flow rate, the optimal installation parameters (x, y, z, α) of the submersible mixer are determined.

[0024] The present invention only needs to use CFD software for calculation, which is more economical, convenient and quicker than experiments.

[0025] Note that the description of these effects does not prevent the existence of other effects. One embodiment of the present invention does not necessarily have all of the above effects. Effects other than the above can be clearly seen and extracted from the description of the specification, drawings, claims, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of a water pool according to one embodiment of the present invention.

[0027] Figure 2 It is a schematic diagram of the installation position on a certain cross section of one embodiment of the present invention.

[0028] Figure 3 Schematic diagram of the position arrangement of the mixer in the water tank according to one embodiment of the present invention, wherein Figure 3 (a) is a schematic diagram of the pool and coordinate system. Figure 3 (b) is the position layout diagram on section H1, Figure 3 (c) is the position layout diagram on section H2.

[0029] Figure 4 Schematic diagram of the relationship between the installation parameters x, y variables and the fluid characteristics in the pool according to one embodiment of the present invention, wherein Figure 4 (a) is the intercept L 11 The curve diagram of the installation parameter y variable and the average velocity and velocity uniformity of the fluid in the pool under this parameter, Figure 4 (b) is the intercept line L 11 The curve diagram of the installation parameter y variable and the ineffective stirring ratio and efficient stirring ratio of the fluid in the pool under this parameter, Figure 4 (c) is the intercept line L 12 The curve diagram of the installation parameter y variable and the average velocity and velocity uniformity of the fluid in the pool under this parameter, Figure 4 (d) is the intercept line L 12 The curve diagram of the installation parameter y variable and the ineffective stirring ratio and efficient stirring ratio of the fluid in the pool under this parameter, Figure 4 (f) is the intercept line L 21 The curve diagram of the installation parameter y variable and the average velocity and velocity uniformity of the fluid in the pool under this parameter, Figure 4 (g) is the intercept line L 21The curve diagram of the installation parameter y variable and the ineffective stirring ratio and efficient stirring ratio of the fluid in the pool under this parameter, Figure 4 (h) is the intercept line L 22 The curve diagram of the installation parameter y variable and the average velocity and velocity uniformity of the fluid in the pool under this parameter, Figure 4 (i) is the intercept L 22 A curve chart of the installation parameter y variable and the ineffective stirring ratio and efficient stirring ratio of the fluid in the pool under this parameter.

[0030] Figure 5 It is a comparison diagram of the ineffective stirring ratio and the efficient stirring ratio of the fluid in the pool at the four optimal installation positions according to one embodiment of the present invention.

[0031] Figure 6 It is a schematic diagram of the installation angle α of a submersible mixer according to one embodiment of the present invention.

[0032] Figure 7 It is a fitting curve diagram of the installation angle α of the submersible mixer according to one embodiment of the present invention and the average velocity of the stirring fluid in the tank at the angle.

[0033] Figure 8 is a curve diagram of the installation angle α variable and the flow field characteristics of the fluid in the pool under this parameter according to an embodiment of the present invention, wherein Figure 8 (a) is a curve diagram of the installation angle α variable and the average velocity and velocity uniformity of the fluid in the pool under this parameter. Figure 8 (b) is a curve diagram of the installation angle α variable and the volume percentage of ineffective stirring fluid and the volume percentage of efficient stirring fluid in the pool under this parameter. DETAILED DESCRIPTION

[0034] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0035] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "front", "back", "left", "right", "up", "down", "axial", "radial", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0036] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] A method for determining optimal installation parameters of a submersible mixer comprises the following steps:

[0038] Establishing 3D model: Establishing simulation 3D models of the submersible mixer and the water tank, and installing the simulation 3D model of the submersible mixer in the simulation 3D model of the water tank;

[0039] Determine the optimal installation position: when the submersible mixer simulation 3D model is installed at different positions of the water pool simulation 3D model, the stirring flow field in the stirring pool is stirred, and the software is used to calculate and draw the curve diagram of the submersible mixer installation position variable and the average fluid velocity, the curve diagram of the installation position variable and the flow velocity uniformity of the stirring fluid in the pool, the curve diagram of the installation position variable and the invalid stirring volume proportion of the stirring fluid in the pool, and the curve diagram of the installation position variable and the efficient stirring volume proportion of the stirring fluid in the pool; find the point with the largest slope on the curve diagram of the submersible mixer installation position variable and the average fluid velocity, and preliminarily infer several optimal installation positions; then combine the curve diagram of the installation position variable and the flow velocity uniformity of the stirring fluid in the pool, the curve diagram of the installation position variable and the invalid stirring volume proportion of the stirring fluid in the pool, and the curve diagram of the installation position variable and the efficient stirring volume proportion of the stirring fluid in the pool, and comprehensively consider the uniformity of the fluid velocity, the peak value of the invalid stirring volume and the efficient stirring volume, and finally determine an optimal installation position from several preliminarily inferred optimal installation positions;

[0040] Determine the optimal installation angle: install the submersible mixer at the optimal installation position, set multiple horizontal inclination angles of the submersible mixer, calculate the mixing flow field when the submersible mixer is installed at different angles, draw the fitting curve of the average speed of the mixing fluid and the deflection angle of the mixer at different installation angles, and find the horizontal inclination angle corresponding to the maximum change rate of the speed curve in the fitting curve. This inclination angle is the optimal installation angle.

[0041] Preferably, the uniformity of the comprehensive fluid velocity, the peak values ​​of the proportion of the ineffective stirring volume and the efficient stirring volume are finally used to determine an optimal installation position from several optimal installation positions preliminarily inferred, specifically: the installation position that satisfies the maximum uniformity of the fluid velocity, the maximum proportion of the efficient stirring volume, and the minimum proportion of the ineffective stirring fluid volume.

[0042] Specifically, the submersible mixer simulation 3D model is installed in the water tank simulation 3D model:

[0043] like Figure 1 As shown, the center of the pool is point o, the coordinates of point o are (0, 0, 0.5H), H is the height of the pool, and the mixing shaft of the submersible mixer is parallel to the long side L of the pool, which is the x direction. For the installation position, one of the installation parameters, the main consideration is the change of the installation position in the x, y, and z coordinates.

[0044] Select several sections H1, H2, ...H with different heights along the height direction of the pool bottom. i , i = 1, 2, 3 ... n, n is a positive integer and is the total number of planes divided; section H i Parallel to the pool bottom, at section H i Cut several line segments L on i1 , Li2 ,…L ij , j = 1, 2, 3...m, m is a positive integer and is the number of line segments selected on the plane; in L ij Several installation positions are selected and the submersible mixers are installed at these installation positions in turn. The average fluid velocity, fluid flow rate uniformity, ineffective stirring volume proportion and efficient stirring volume proportion are calculated by software.

[0045] The submersible mixer is installed on a line segment L ij As the installation position of the submersible mixer moves along the positive direction of the Y axis, the average velocity of the fluid in the pool increases rapidly and eventually stabilizes. Assuming that Y = y i When , the slope of the curve of the installation position variable and the average velocity of the stirring fluid in the pool is the largest at this point, and the i×j optimal installation positions are preliminarily inferred.

[0046] Compare the i×j best installation positions, fluid velocity uniformity, the proportion of ineffective stirring volume and efficient stirring volume. Suppose at a certain point (x, y, z), the fluid uniformity is the largest, the proportion of efficient stirring volume is the largest, the proportion of ineffective stirring volume is the smallest, and the stirring effect is the best. Then the best installation position is determined to be (x, y, z).

[0047] At the optimal installation position (x, y, z), the installation angle α of the submersible mixer is used as the variable α1, α2, ... α n , n is the number of installation angles; numerical calculations are performed for different installation angles to obtain the average flow velocity of the fluid in the mixing tank, and a curve diagram of the installation angle variable and the average flow velocity is drawn. The angle variable corresponding to the point where the velocity change curvature is the largest in the curve diagram is the optimal installation angle, and the optimal installation parameters of the submersible mixer can be obtained as (x, y, z, α).

[0048] In a specific embodiment of the present invention, Figure 2 As shown, in section L i On the top, the horizontal lines are cut at 0.1H, 0.2H, 0.3H, 0.4H, 0.5H (not limited to this) from the bottom of the pool, respectively, L i1 , L i2 , L i3 , L i4 , L i5 , these lines are perpendicular to the mixing shaft of the submersible mixer. The installation positions are set on the lines in sequence, and the distances from the center are 0.1B, 0.2B, 0.3B, 0.4B, and 0.5B respectively. A can be obtained in sequence 11 , A 12 , A 13 , A 14 , A 15 , A 21 , A 22 , A23 , A 24 , A 25 , A 31 , A 32 , A 33 , A 34 , A 35 , A 41 , A 42 , A 43 , A 44 , A 45 , A 51 , A 52 , A 53 , A 54 , A 55 Through CFD software, the stirring flow field and the average velocity of the fluid in the stirring tank can be calculated when the submersible mixer is installed in the above positions. i1 , plot the average speed vs. installation position A 1j Coordinate diagram, the horizontal axis is the coordinate variable of the submersible mixer installation position, the vertical axis is the average speed of the mixing flow field when the submersible mixer is installed at this position, and the curve diagram is obtained by connecting each point. The point with the largest curvature of speed change in the curve diagram is the best submersible mixer installation position A1 on the section line L1, which is preliminarily inferred as the best installation position.

[0049] For the intercept L i2 , L i3 , L i4 , L i5 , draw the corresponding curve graph, find the best submersible mixer installation position A2, A3, A4, A5 on each section line, and preliminarily infer it as the best installation position.

[0050] From these five installation positions that are preliminarily inferred as the best, combined with the uniformity of the fluid velocity, the peak values ​​of the ineffective stirring volume and the efficient stirring volume, an optimal installation position is determined from the several optimal installation positions preliminarily inferred.

[0051] Similarly, for the stirring angle α, one of the installation parameters, its parameter variable is the inclination angle of the mixer, where 0° is the angle at which the shaft of the submersible mixer is parallel to the x-axis of the length of the pool.

[0052] At the optimal installation position found above, the installation angle α of the submersible mixer is taken as variables α1, α2, α3, α4, α5 (not limited to these angles), and numerical calculations are performed for different installation angles to obtain the average flow velocity of the fluid in the mixing tank. A graph of the installation angle variable and the average flow velocity is drawn. The angle variable corresponding to the point in the graph where the curvature of the velocity change is the largest is the optimal installation angle.

[0053] Thus, the optimal installation parameters (x, y, z, α) of the submersible mixer can be obtained.

[0054] Example 1

[0055] like Figure 3 As shown, the dimensions of the square pool are 4m long, 3m wide, and 2m high, and the fluid volume is 24m 3 Point o is the center of the pool, with coordinates (0, 0, 1). Point O1 is the center of the pool bottom plane, with coordinates (0, 0, 0). The submersible mixer's rotation axis is parallel to the pool length, in the x direction. Section H1 is parallel to the pool bottom and is 1m away from the pool bottom; section H2 is parallel to the pool bottom and is 0.5m away from the pool bottom. The submersible mixer is installed close to the pool wall, such as Figure 3 (a) As shown. In section H1, cut line segments L 11 and L 12 , L 11 Select 8 installable positions, namely A 10 (-0.5, 0, 0.5), A 11 (-0.5, 0.2, 0.5), A 12 (-0.5, 0.4, 0.5), A 13 (-0.5, 0.6, 0.5), A 14 (-0.5, 0.8, 0.5), A 15 (-0.5, 1.0, 0.5), A 16 (-0.5, 1.2, 0.5), A 17 (-0.5, 1.4, 0.5), L 12 Select 8 installable positions, namely A 20 (-1.5, 0, 0.5), A 21 (-1.5, 0.2, 0.5), A 22 (-1.5, 0.4, 0.5), A 23 (-1.5, 0.6, 0.5), A 24 (-1.5, 0.8, 0.5), A 25 (-1.5, 1.0, 0.5), A 26 (-1.5, 1.2, 0.5), A 27 (-1.5, 1.4, 0.5), such as Figure 3 (b) as shown.

[0056] Take line segment L at section H2 21 and L 22 , L 21 Select 8 installable positions, namely B 10 (-0.5, 0, 1), B 11(-0.5, 0.2, 1), B 12 (-0.5, 0.4, 1), B 13 (-0.5, 0.6, 1), B 14 (-0.5, 0.8, 1), B 15 (-0.5, 1.0, 1), B 16 (-0.5, 1.2, 1), B 17 (-0.5, 1.4, 1), L 22 Select 8 installable positions, namely B 20 (-1.5, 0, 1), B 21 (-1.5, 0.2, 1), B 22 (-1.5, 0.4, 1), B 23 (-1.5, 0.6, 1), B 24 (-1.5, 0.8, 1), B 25 (-1.5, 1.0, 1), B 26 (-1.5, 1.2, 1), B 27 (-1.5, 1.4, 1), such as Figure 3 (c) as shown.

[0057] The submersible mixers were installed at these 32 positions in turn, and numerical calculations and analyses were performed respectively. The installation position variables and the average velocity curve of the stirring fluid in the pool were plotted, the installation position variables and the velocity uniformity curve of the stirring fluid in the pool were plotted, the installation position variables and the proportion of the ineffective stirring volume of the stirring fluid in the pool were plotted, and the installation position variables and the proportion of the efficient stirring volume of the stirring fluid in the pool were plotted.

[0058] Figure 4 It is a schematic diagram of the relationship between the installation parameters x and y variables and the fluid characteristics in the pool, where Figure 4 (a) is the intercept L 11 The curve diagram of the installation parameter y variable and the average velocity and velocity uniformity of the fluid in the pool under this parameter, Figure 4 (b) is the intercept line L 11 The curve diagram of the installation parameter y variable and the ineffective stirring ratio and efficient stirring ratio of the fluid in the pool under this parameter, Figure 4 (c) is the intercept line L 12 The curve diagram of the installation parameter y variable and the average velocity and velocity uniformity of the fluid in the pool under this parameter, Figure 4 (d) is the intercept line L 12 The curve diagram of the installation parameter y variable and the ineffective stirring ratio and efficient stirring ratio of the fluid in the pool under this parameter, Figure 4 (f) is the intercept line L 21 The curve diagram of the installation parameter y variable and the average velocity and velocity uniformity of the fluid in the pool under this parameter, Figure 4(g) is the intercept line L 21 The curve diagram of the installation parameter y variable and the ineffective stirring ratio and efficient stirring ratio of the fluid in the pool under this parameter, Figure 4 (h) is the intercept line L 22 The curve diagram of the installation parameter y variable and the average velocity and velocity uniformity of the fluid in the pool under this parameter, Figure 4 (i) is the intercept L 22 The curve diagram of the installation parameter y variable and the ineffective stirring ratio and efficient stirring ratio of the fluid in the pool under this parameter. Figure 4 It can be seen that as the installation position of the submersible mixer moves in the positive direction along the Y axis, the average velocity of the fluid in the pool increases rapidly and eventually stabilizes. When Y=0.6m, the slope of the curve of the installation position variable and the average velocity of the stirring fluid in the pool is the largest at this point. 13 , A 23 , B 13 , B 23 These are four preliminary inferred optimal installation positions.

[0059] Compared with other curves, the uniformity of the fluid velocity decreases rapidly after reaching the maximum value, and the maximum value occurs exactly at Y=0.6m, that is, the point where the slope of the curve of the installation position variable and the average velocity of the stirring fluid in the pool is the largest.

[0060] As the installation position moves in the positive direction along the Y axis (Y>0), the percentages of ineffective stirring volume and efficient stirring volume both reach peak values. The extreme point of the percentage of efficient fluid volume, that is, the maximum percentage of efficient fluid volume, corresponds to the installation position of the submersible mixer at Y=0.6m, that is, the point where the slope of the curve of the installation position variable and the average velocity of the stirring fluid in the tank is the largest. When the mixer is installed at Y=0.6m, the percentage of efficient stirring volume reaches the maximum, and the percentage of ineffective stirring volume is less than 1%, and the stirring effect is optimal.

[0061] Based on the above analysis, the stirring performance is indeed the best at the optimal installation position obtained by the method of the present invention.

[0062] Then, compare A 13 , A 23 , B 13 , B 23 The four initially inferred optimal installation positions are compared with their efficient stirring fluid volume ratio, such as Figure 5 As shown, A 13 This is the optimal installation position finally determined. In this position, the average fluid velocity exceeds 0.5m / s, the effective stirring volume accounts for more than 99%, and the high-efficiency stirring volume accounts for more than 64%, showing excellent stirring performance.

[0063] It shows that by plotting the installation position variable of the submersible mixer and the average fluid velocity curve, the point with the largest slope on the fluid velocity curve can be found, which can be preliminarily inferred as the optimal installation position of the mixer. According to this method, several inferred optimal installation positions of the mixer can be found, and then combined with the uniformity of the fluid velocity, the peak value of the proportion of the ineffective stirring volume and the efficient stirring volume, an optimal installation position can be determined from the several preliminarily inferred optimal installation positions.

[0064] Install the submersible mixer in A 13 Location, such as Figure 6 As shown, the horizontal inclination angles are set to -15°, -10°, -6°, -3°, 3°, 6°, 10° and 15°.

[0065] The speed fitting curves of different mixer deflection angles are studied, such as Figure 7 As shown, the maximum rate of change of the velocity curve is between -3° and 0°, so it can be determined that the optimal deflection angle is between -3° and 0°.

[0066] like Figure 8 As shown in , as the deflection angle increases, the average velocity and uniformity of the flow field gradually increase and eventually tend to be stable. Figure 8 As shown in (a), when the deflection angle is 0°, the flow field uniformity reaches the maximum value, and the proportion of the efficient stirring area also reaches the maximum value, as shown in Figure 8 As shown in (b), the best installation angle is 0°.

[0067] Thus, the optimal installation parameters of the mixer in the pool can be obtained (-0.5, 0.6, 1, 0).

[0068] The submersible mixer can be installed at any position and angle in the water tank. The submersible mixer is installed at a certain position in the water tank. Through numerical calculation, the mixing situation in the water tank, such as the average velocity in the water tank, can be obtained. The mixing flow field of each installation parameter is calculated separately to obtain the average velocity of the fluid in the flow field under the parameter. There is a certain relationship between the average velocity of the fluid in the pool and the coordinates of the parameter variable. Through the curve of the submersible mixer installation position variable and the average velocity of the fluid, the maximum slope on the curve is found, and several optimal installation positions are preliminarily inferred. Then, combined with the uniformity of the fluid velocity, the peak value of the proportion of the ineffective mixing volume and the efficient mixing volume, an optimal installation position is determined from the several optimal installation positions preliminarily inferred; the submersible mixer is installed at the optimal installation position, and multiple horizontal inclination angles of the submersible mixer are set. The average velocity of the fluid in the mixing flow field when the submersible mixer is installed at different angles is calculated separately, and the horizontal inclination corresponding to the maximum change rate of the velocity curve in the fitting curve of the average velocity of the mixer mixing fluid and the mixer deflection angle at different installation angles is found as the optimal installation angle, and the optimal installation parameters of the submersible mixer are obtained. This can quickly and easily find the best installation parameters for the submersible mixer, so that the mixer has the best mixing effect and the liquid is fully mixed. The mixing dead zone in the tank is the smallest, and the average mixing speed meets the mixing requirements.

[0069] The method for determining the optimal installation parameters of a submersible mixer described in the present invention is an optimization effect speed evaluation method, which is a simple and efficient mixer installation position evaluation tool. It can quickly and conveniently find the optimal submersible mixer installation position and installation angle, so that the mixer has the best mixing effect, the least mixing dead zone in the tank, and the average mixing speed meets the mixing requirements.

[0070] It should be understood that although this specification is described according to various embodiments, not every embodiment contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0071] The series of detailed descriptions listed above are only specific descriptions of feasible embodiments of the present invention. They are not intended to limit the scope of protection of the present invention. All equivalent embodiments or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for determining optimal installation parameters of a submersible mixer, characterized in that: The following steps are involved: Establishing 3D model: Establishing simulation 3D models of the submersible mixer and the water tank, and installing the simulation 3D model of the submersible mixer in the simulation 3D model of the water tank; Determine the optimal installation position: When the submersible mixer simulation 3D model is installed at different positions of the water tank simulation 3D model, the stirring flow field in the stirring water tank is stirred, and the average fluid velocity, fluid velocity uniformity, invalid stirring volume ratio and efficient stirring volume ratio are calculated by software. The maximum slope of the curve of the submersible mixer installation position variable and the average fluid velocity is found, and several optimal installation positions are preliminarily inferred. Then, combined with the uniformity of the fluid velocity, the peak values ​​of the invalid stirring volume and the efficient stirring volume ratio, an optimal installation position is determined from the several optimal installation positions preliminarily inferred. Determine the optimal installation angle: install the submersible mixer at the optimal installation position, set multiple horizontal inclination angles of the submersible mixer, calculate the average velocity of the fluid in the mixing flow field when the submersible mixer is installed at different angles, and find the horizontal inclination angle corresponding to the maximum change rate of the velocity curve in the fitting curve of the average velocity of the mixing fluid of the mixer and the deflection angle of the mixer at different installation angles as the optimal installation angle.

2. The method for determining the optimal installation parameters of a submersible mixer according to claim 1, characterized in that: The software is CFD software.

3. The method for determining the optimal installation parameters of a submersible mixer according to claim 1, characterized in that: The steps of determining the optimal installation position are specifically as follows: When the submersible mixer simulation three-dimensional model is installed at different positions of the water tank simulation three-dimensional model, the stirring flow field in the stirring water tank is stirred, and the software is used to calculate and draw the submersible mixer installation position variable and the fluid average velocity curve, the installation position variable and the stirring fluid flow velocity uniformity curve in the tank, the installation position variable and the ineffective stirring volume ratio curve of the stirring fluid in the tank, and the installation position variable and the efficient stirring volume ratio curve of the stirring fluid in the tank; the submersible mixer installation position variable and the fluid average velocity curve are used to find the point with the largest slope on the curve, and preliminarily infer several optimal installation positions; then combined with the installation position variable and the stirring fluid flow velocity uniformity curve in the tank, the installation position variable and the ineffective stirring volume ratio curve of the stirring fluid in the tank, and the installation position variable and the efficient stirring volume ratio curve of the stirring fluid in the tank, the uniformity of the fluid velocity, the peak value of the invalid stirring volume and the efficient stirring volume are comprehensively considered, and finally an optimal installation position is determined from the several optimal installation positions preliminarily inferred.

4. The method for determining the optimal installation parameters of a submersible mixer according to claim 3, characterized in that: The uniformity of the comprehensive fluid velocity, the peak values ​​of the proportion of the ineffective stirring volume and the efficient stirring volume are finally determined from several optimal installation positions preliminarily inferred, specifically: the installation position that satisfies the maximum uniformity of the fluid velocity, the maximum proportion of the efficient stirring volume, and the minimum proportion of the ineffective stirring fluid volume.

5. The method for determining optimal installation parameters of a submersible mixer according to claim 1, characterized in that: The steps of determining the optimal installation angle are specifically as follows: The submersible mixer is installed at the optimal installation position, and multiple horizontal inclination angles of the submersible mixer are set. The mixing flow field when the submersible mixer is installed at different angles is calculated respectively. The fitting curves of the average velocity of the mixing fluid and the deflection angle of the mixer at different installation angles are drawn, and the horizontal inclination angle corresponding to the maximum change rate of the velocity curve in the fitting curve is found. This inclination angle is the optimal installation angle.

6. The method for determining optimal installation parameters of a submersible mixer according to claim 1, characterized in that: Install the submersible mixer simulation 3D model in the pool simulation 3D model: The center of the pool is point o, and the coordinates of point o are (0, 0, 0.5H). H is the height of the pool. The mixing shaft of the submersible mixer is parallel to the long side L of the pool, which is the x direction.

7. The method for determining optimal installation parameters of a submersible mixer according to claim 6, characterized in that: Select several sections H with different heights along the height direction of the pool bottom. i , i = 1, 2, 3...n, n is a positive integer; cross section H i Parallel to the pool bottom, at section H i Cut several line segments L on ij , j = 1, 2, 3 ... m, m is a positive integer; in L ij Several installation positions are selected and the submersible mixers are installed at these installation positions in turn. The average fluid velocity, fluid flow rate uniformity, ineffective stirring volume proportion and efficient stirring volume proportion are calculated by software.

8. The method for determining optimal installation parameters of a submersible mixer according to claim 7, characterized in that: On line segment L ij ,As the installation position of the submersible mixer moves along the positive direction of the Y axis, the average velocity of the fluid in the pool increases rapidly and eventually stabilizes. Assuming that Y = y i When , the slope of the curve of the installation position variable and the average velocity of the stirring fluid in the pool is the largest at this point, and the i×j optimal installation positions are preliminarily inferred.

9. The method for determining optimal installation parameters of a submersible mixer according to claim 8, characterized in that: Compare the fluid flow rate uniformity, efficient stirring volume proportion, and ineffective stirring volume proportion at the i×j optimal installation positions. When the mixer is installed at one of the positions, the fluid flow rate uniformity is optimal, the efficient stirring volume proportion reaches the maximum, the ineffective stirring volume proportion is the minimum, and the stirring effect is optimal. This position is determined to be the optimal installation position (x, y, z).

10. The method for determining optimal installation parameters of a submersible mixer according to claim 9, characterized in that: At the optimal installation position (x, y, z), the installation angle α of the submersible mixer is used as the variable α1, α2, ... α n , n is the number of installation angles; numerical calculations are performed for different installation angles to obtain the average flow velocity of the fluid in the mixing tank, and a curve diagram of the installation angle variable and the average flow velocity is drawn. The angle variable corresponding to the point where the velocity change curvature is the largest in the curve diagram is the optimal installation angle, and the optimal installation parameters of the submersible mixer can be obtained as (x, y, z, α).

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