CN105044382A - Test board for measuring overall flow velocity of submersible mixer, and method for measuring overall flow velocity of submersible mixer - Google Patents

Abstract

The invention belongs to the technical field of fluid and chemical engineering, and relates to a test board for measuring the overall flow velocity of a submersible mixer and a method for measuring the overall flow velocity of a submersible mixer. The test board comprises a submersible mixer and a cone-shaped five-hole probe which are arranged in a sewage treatment pool, wherein the sewage treatment pool is a road-shaped pool; the cone-shaped five-hole probe is connected with an input end of a signal collector through a pressure sensor; and an output end of the signal collector is connected with a computer. The test board for measuring the overall flow velocity of a submersible mixer can measure the overall flow velocity of a submersible mixer by means of the integral principle, wherein the measuring process includes starting measurement from the position which is about 40mm apart from an impeller axis of the submersible mixer (dmin=40mm); moving to two sides point by point by the increment (each d=80) to measure the mean flow velocity in each anchor ring until the measured mean flow velocity is less than the minimum flow velocity Vmin so as to determine the maximum diameter dmax of a circle; and then obtaining the overall flow velocity. The invention provides the method for measuring the overall flow velocity of the submersible mixer, and designs the test board for measuring the overall flow velocity of the submersible mixer for the measuring method, thus being able to provide accurate experimental data for a factory inspection report of the mixer.

Description

A test bench and method for measuring the overall flow rate of a submersible mixer

technical field

The invention relates to the technical fields of fluid and chemical industry, in particular to a test bench and method for measuring the overall flow velocity of a submersible mixer.

Background technique

Sewage treatment is an important measure for environmental protection departments and enterprises to solve wastewater pollution in environmental pollution. Submersible mixer is a new type of efficient sewage treatment mixing machine, which is widely used in industrial, urban and rural sewage treatment. The submersible mixer for sewage is a kind of forced mixing equipment, which is suitable for mixing various types of sewage treatment. It can stir and mix the surrounding water body, thereby improving the efficiency of sewage treatment.

Effective agitation is achieved under bulk flow conditions, where the media in the tank as a whole is in motion and becomes part of the agitation process. To this day, bulk flow rate is still the most feasible method for quantitative analysis of general agitation state in wastewater treatment. The effective stirring of the submersible mixer is obtained under the overall flow condition, and its flow rate is usually 0.15-0.35m/s. The overall flow is driven by the momentum of the agitator jet, which is essentially the reactive thrust of the agitator, which together with the position of the agitator determines the resulting flow pattern. If the position of the agitator and the thrust required for an application and the thrust data of the agitator are known, the equipment can be selected accordingly. However, most of the current mixers are selected according to the size of the mixing tank, the water depth and the parameters of the medium, such as: suspended solids content, viscosity, etc., and the overall flow rate of the mixing degree of the submersible mixer cannot be given quantitatively, which is difficult to meet industrial production. demand.

In order to solve the above problems, it is very necessary to develop a method and test bench for measuring the overall flow rate of the submersible mixer, and its related technologies have not been reported at home and abroad.

Contents of the invention

The object of the present invention is to propose a test bench and method for measuring the overall flow velocity of a submersible mixer in view of the problem that the overall flow velocity of the agitation degree of the submersible mixer cannot be given quantitatively at present, and it is difficult to meet the needs of industrial production.

The technical solution of the present invention is: a test bench for measuring the overall flow velocity of a submersible mixer, which is characterized in that it includes: a submersible mixer and a conical five-hole probe placed in a sewage treatment tank; the center of the impeller of the submersible mixer The axis is on the same level as the middle hole of the tapered five-hole probe;

The middle position of the channel on one side of the sewage treatment pool is provided with a test bench arrangement area T, and two parallel tracks A are arranged on both sides of the top opening of the test bench arrangement area T, and a pedal is provided between the two guide rails A. The pedal can move back and forth along the guide rail A, a track B is vertically fixed at the middle position of the bottom of the test area, and a bracket is vertically fixed on the track B;

The submersible mixer is placed on the bracket; the submersible mixer is connected to the control cabinet through cables;

The tapered five-hole probe is fixedly connected with a fixed bracket, and the fixed bracket is slidingly linked with a guide rail C, and the fixed bracket can move left and right along the guide rail C, and the guide rail C is fixedly linked with the pedal; The tapered five-hole probe is connected to the input end of the signal collector through a pressure sensor, and the output end of the signal collector is connected to a computer.

In the above solution, the sewage treatment pool is a road-shaped pool.

In the above scheme, there are at least two tapered five-hole probes.

In the above solution, the fixed bracket includes a groove connected with the guide rail C, a vertical bar is fixed on the groove, a support arm is fixed on the vertical bar, and a clamp is provided at the end of the support arm , the tapered five-hole probe is fastened on the fixture by bolts.

In the above solution, both ends of the guide rail C are fixedly linked with the pedal through a cross bar.

A method of measuring the overall flow rate of a submersible mixer, comprising the steps of:

S1. Install the submersible mixer:

Lift the submersible mixer with a sling, and place the submersible mixer on the bracket along the guide rail B;

S2. Adjust the position of the tapered five-hole probe on the fixed bracket:

Make the middle hole of the conical five-hole probe and the central axis of the impeller of the submersible mixer on the same horizontal plane, and fix the conical five-hole probe after centering;

S3. Adjust the measurement position of the tapered five-hole probe:

Moving the fixed bracket left and right along the pedal, so that the tapered five-hole probes on the two fixed brackets are respectively in the position I and its symmetry, and the fixed bracket is fixed after the position is adjusted;

S4, adjusting the distance between the tapered five-hole probe and the submersible mixer;

Move the pedal along the guide rail A, so that the distance between the top of the tapered five-hole probe and the plane where the impeller of the submersible mixer is located is n times the diameter of the impeller, and the pedal is fixed;

S5. Complete the connection of the test bench:

connecting the cables into the control cabinet;

The tapered five-hole probe is sequentially connected with the pressure sensor, the signal collector and the computer;

S6, start the submersible mixer:

Control the submersible mixer to run for at least 20 minutes at rated voltage and rated frequency through the control cabinet to stabilize the flow field;

S7. Read measurement data:

Read the average flow velocity displayed on the computer at the symmetrical measurement point, start measuring from the minimum diameter d _min , and make the fixed bracket drive the tapered five-hole probe along the guide rail with a diameter increment of every d C moves point by point to both ends until the measured average velocity drops below V _min , then the maximum diameter d _max of the circle is determined;

Step8) utilize integral principle to measure the overall flow rate of described submersible mixer:

${\mathrm{<span\; class="notranslate">\; Q</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; min</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; II</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; Q</span>}}_{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; N</span>}}<span\; class="notranslate">\; =</span>\frac{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}}}{\mathrm{<span\; class="notranslate">\; \&pi;d</span>}}_{\mathrm{<span\; class="notranslate">\; min</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; +</span>\frac{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; II</span>}}}\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; II</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; +</span>\frac{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}}}\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; 4</span>}}$

${\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; av</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 4</span>}\mathrm{<span\; class="notranslate">\; Q</span>}}{{\mathrm{<span\; class="notranslate">\; \&pi;d</span>}}_{\mathrm{<span\; class="notranslate">\; max</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; .</span>$

In the formula, Q _min is the inner circular flow rate, Q _I-II is the circular flow rate of I-II, Q _(N-1)-N is the circular flow rate of (N-1)-N, is the average value of the velocity at both ends of I, is the average value of the velocity at both ends of II, is the average value of flow velocity at both ends of N, d _min is the minimum diameter of the circle, d _I is the diameter of the circle where I is located, d _N is the diameter of the circle where N is located, π is a constant, V _av is the overall flow velocity, and d _max is the diameter of the circle The maximum diameter.

In the above scheme, it also includes the determination step that the minimum flow velocity is V _min : the three-dimensional modeling of the submersible mixer UG is placed in a pipe with 1.12 times the diameter of the impeller, and the water body is extracted, and the ICEM large-scale grid software is used to divide the grid, and the CFD software is used to Numerical simulation of the water body is carried out. When Q _m = (1-1.05) Q _t , where Q _m is the simulated flow rate, Q _t is the test-measured flow rate, and the minimum flow rate is V _min = 0.105-0.114m/s.

Further, the V _min =0.11m/s.

In the above scheme, n=3 in S4, the distance between the tip of the tapered five-hole probe and the plane where the impeller of the submersible mixer is located is 3 times the diameter of the impeller, ie L=3×Φd.

In the above solution, the d _min =40mm, and the d=80mm.

The beneficial effects of the present invention are:

1. The test is carried out in the road-shaped pool, so that the mainstream of the liquid flow generated when the submersible mixer is running can flow in one direction to avoid liquid back-mixing, thereby ensuring the stability of the flow field and improving the test accuracy;

2. The central axis of the impeller of the submersible mixer is on the same level as the middle hole of the tapered five-hole probe, which makes the measurement more accurate;

3. The minimum water velocity is determined to be V _min = 0.11m/s, which can meet the flow test requirements of different types of submersible mixers selected at the same time, and has wider applicability;

4. The distance between the top of the conical five-hole probe and the plane where the impeller of the submersible mixer is located is 3 times the diameter of the impeller, that is, L=3×Φd. The flow field here is more stable, which is conducive to improving the test accuracy ;

5. The d _min = 40mm, and the d = 80mm can better meet the accuracy requirements and save measurement time;

6. The present invention uses the integration principle to determine the overall flow velocity of the agitator, provides a measurement method for the overall flow velocity of the agitator, and designs a test bench for measuring the overall flow velocity of the submersible agitator to provide accurate results for the agitator factory report. Experimental data.

Description of drawings

Fig. 1 is the local three-dimensional perspective view of test bench of the present invention;

Fig. 2 is the outline drawing of road shape pool;

Fig. 3 is the front view of test bench of the present invention;

Fig. 4 is the enlarged view of M place in Fig. 3;

Fig. 5 is the top view of test stand of the present invention;

Fig. 6 is a schematic diagram of the present invention for calculating the flow rate.

In the figure: 1. Guide rail A; 2. Fixed bracket; 201. Groove; 202. Vertical bar; 203. Support arm; 204. Clamp; 3. Pressure sensor; 4. Guide rail B; ;7, submersible mixer; 8, tapered five-hole probe; 9, bracket; 10, pedal; 11, guide rail C; 1101, cross bar; 12, signal collector; 13, computer; 14, control cabinet; 15. Sewage treatment pool; 16 Test bench layout area T.

Detailed ways

In describing the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer" ” and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, with a specific configuration and operation, and therefore should not be construed as limiting the invention.

In the present invention, unless otherwise clearly specified and limited, terms such as "installation", "connection", "connection" and "fixation" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection , or integrally connected; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary, and it may be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

In the present invention, unless otherwise clearly specified and limited, a first feature being "on" or "under" a second feature may include direct contact between the first and second features, and may also include the first and second features Not in direct contact but through another characteristic contact between them. Moreover, "above", "above" and "above" the first feature on the second feature include that the first feature is directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature. "Below", "beneath" and "under" the first feature to the second feature include that the first feature is directly below and obliquely below the second feature, or simply means that the first feature has a lower level than the second feature.

The present invention will be described in further detail below in conjunction with the specific embodiments of the accompanying drawings, but the protection scope of the present invention is not limited thereto.

As shown in FIG. 1 , a test bench for measuring the overall flow rate of a submersible mixer includes: a submersible mixer 7 and a conical five-hole probe 8 placed in a sewage treatment tank 15 .

As shown in Figure 2, the sewage treatment pool 15 is a road-shaped pool (but not limited thereto), and its function is mainly to make the liquid flow generated when the submersible mixer is running to flow along the direction shown by the arrow in the figure, so as to avoid The liquid is back mixed to ensure the stability of the flow field and improve the test accuracy.

As shown in FIG. 3 , the central axis of the impeller of the submersible mixer 7 is on the same level as the middle hole of the tapered five-hole probe 8 .

The middle position of the channel on one side of the sewage treatment pool 15 is provided with a test bench arrangement area T16, and two rails A1 parallel to each other are arranged on both sides of the top opening of the test bench arrangement area T16, and a pedal 10 is arranged between the two guide rails A1. , the pedal 10 can move back and forth along the guide rail A1, a track B4 is vertically fixed in the middle of the bottom of the test area 15, and a bracket 9 is vertically fixed and welded on the track B4, and the bracket 9 is far from the sewage treatment The pool bottom of the pool 15 is h=3m; the submersible mixer 7 is placed on the bracket 9 ; the submersible mixer 7 is connected to the control cabinet 14 through a cable 5 .

As shown in Figure 4, the fixed bracket 2 includes a groove 201 connected with the guide rail C11, a vertical bar 202 is fixed on the groove 201, and a support arm 203 is fixed on the vertical bar 202, so that A clamp 204 is provided at the end of the support arm 203, and the tapered five-hole probe 8 is fastened to the clamp 204 by bolts.

Both ends of the guide rail C11 are fixedly linked with the pedal 10 through cross bars 1101 , the fixed bracket 2 can move left and right along the guide rail C11 , and can also move forward and backward together with the pedal 10 after being fixed.

There are at least two tapered five-hole probes 8, and each of the tapered five-hole probes 8 is connected to a pressure sensor 3 separately, and the input end of the tapered five-hole probe 8 and the signal collector 12 The output terminal of the signal collector 12 is connected with the computer 13 through the connection of the pressure sensor 3 .

A method of measuring the bulk flow rate of a submersible mixer comprising the following test preparation and test phases:

The test preparation phase includes the following steps:

S1. Install the submersible mixer 7:

Lift the submersible mixer 7 with a sling 6, and place the submersible mixer 7 on the bracket 9 along the guide rail B4;

S2, adjusting the position of the tapered five-hole probe 8 on the fixed bracket 2:

Make the middle hole of the conical five-hole probe 8 and the central axis of the impeller of the submersible mixer 7 on the same horizontal plane, and fix the conical five-hole probe 8 after centering;

S3, adjusting the measuring position of the tapered five-hole probe 8:

The fixed bracket 2 is moved left and right along the pedal 10, so that the tapered five-hole probes 8 on the two fixed brackets 2 are respectively in I and its symmetrical position, and the fixed brackets are fixed after the position adjustment. The fixed bracket 2;

S4, adjusting the distance between the tapered five-hole probe 8 and the submersible mixer 7;

Move the pedal 10 along the guide rail A1 so that the distance between the top of the conical five-hole probe 8 and the plane where the impeller of the submersible mixer 7 is located is 3 times the diameter of the impeller, that is, L=3×Φd, fixed said pedal 10;

S5. Complete the connection of the test bench:

Connect the cable 5 into the control cabinet 14;

The tapered five-hole probe 8 is sequentially connected with the pressure sensor 3 , the signal collector 12 and the computer 13 .

The pilot phase includes the following steps:

S6, start the submersible mixer 7:

Control the submersible mixer 7 by the control cabinet 14 to run at least 20min at rated voltage and rated frequency to stabilize the flow field;

S7. Read measurement data:

Read and display the average flow velocity of the symmetrical measurement point on the computer 13, start measuring from the minimum diameter d _min , make the fixed bracket 2 drive the tapered five-hole probe 8 along the The guide rail C11 moves point by point to both ends until the measured average flow velocity drops below the minimum flow velocity V _min =0.11m/s, then the maximum diameter d _max of the circle is determined;

The method of determining the minimum flow rate V _min : take a submersible mixer with an impeller diameter of 790mm as a sample, conduct UG three-dimensional modeling on it, put it into a pipe with 1.12 times the diameter of the impeller, and extract the water body. The ICEM large-scale grid software is used to divide the grid. CFD software performs numerical simulation on the water body. When Q _m = (1~1.05) Q _t , where Q _m is the simulated flow rate, Q _t is the test measured flow rate, and the minimum flow rate is V _min = 0.105 ~ 0.114m/ s. Select different types of submersible mixers to perform the above operations, and compare the obtained minimum flow rates. We find that V _min = 0.11m/s can meet the flow test requirements of different types of submersible mixers selected at the same time.

The principle of determining the minimum flow rate V _min : For a certain type of submersible mixer, put it into a water pipe with a corresponding diameter for numerical simulation, and the actual flow Q _m of the type of mixer can be obtained, but in the open test tank In the process, the propulsive water flow moves forward in a flame shape, and the flow velocity gradually decreases from the inside to the outside. In the experiment, different minimum water flow velocity V _min can be selected to obtain different maximum diameters, and correspondingly different test flow Q _t can be obtained, so that Equation Q _m = (1～1.05)Q _t There may be many sets of minimum flow rates that meet the requirements, and each set minimum flow rate V _min that meets the requirements can only be adapted to several different types of submersible mixers, but V _min = 0.11m/s can meet the flow test requirements of different types of submersible mixers selected at the same time, and has wider applicability.

S8, using the integration principle to measure the overall flow velocity of the submersible mixer 7:

When the submersible mixer is running, the pushed liquid advances forward in a flame shape, and the symmetrical arrangement of the conical five-hole probe 8 can measure the velocity of two points on the circular boundary of the same diameter on the section. The average flow velocity of any ring should be this The average value of the left and right flow velocity readings on the radius of the ring is measured from a distance of about d _min = 40 mm from the impeller axis, and moves along the pedal 10 point by point to both sides with an increment of every d = 80 mm to measure each The average flow velocity in the torus until the measured average flow velocity is below V _min =0.11 m/s, then the maximum diameter d _max of the circle is determined.

As shown in Figure 6, the flow in the shaded part of the figure is

${\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; II</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; III</span>}}<span\; class="notranslate">\; =</span>\frac{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; III</span>}}}\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; III</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; II</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

In the formula, is the average value of liquid flow velocity at both ends of measuring point III;

Then the overall flow of the submersible mixer 7 is the sum of the flow on each annulus, that is

${\mathrm{<span\; class="notranslate">\; Q</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; min</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; II</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; Q</span>}}_{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; N</span>}}<span\; class="notranslate">\; =</span>\frac{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}}}{\mathrm{<span\; class="notranslate">\; \&pi;d</span>}}_{\mathrm{<span\; class="notranslate">\; min</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; +</span>\frac{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; II</span>}}}\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; II</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&Center\; Dot;</span><span\; class="notranslate">\; +</span>\frac{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}}}\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

The corresponding overall flow rate is:

${\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; av</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 4</span>}\mathrm{<span\; class="notranslate">\; Q</span>}}{{\mathrm{<span\; class="notranslate">\; \&pi;d</span>}}_{\mathrm{<span\; class="notranslate">\; max</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>$

In the formula, Q _min is the inner circular flow rate, Q _I-II is the circular flow rate of I-II, Q _(N-1)-N is the circular flow rate of (N-1)-N, is the average value of the velocity at both ends of I, is the average value of the velocity at both ends of II, is the average value of flow velocity at both ends of N, d _min is the minimum diameter of the circle, d _I is the diameter of the circle where I is located, d _N is the diameter of the circle where N is located, π is a constant, V _av is the overall flow velocity, and d _max is the diameter of the circle The maximum diameter.

The advantages of the present invention are: the test is carried out in the road-shaped pool, so that the main flow of the liquid flow generated when the submersible mixer is running can flow in one direction, avoiding liquid back-mixing, thereby ensuring the stability of the flow field and improving the test accuracy ; The central axis of the impeller of the submersible _mixer is on the same level as the middle hole of the tapered five-hole probe, which makes the measurement more precise; The flow test requirements of different types of submersible mixers have wider applicability; the distance between the top of the conical five-hole probe and the plane where the impeller of the submersible mixer is located is 3 times the diameter of the impeller, that is, L=3× Φd, the flow field here is more stable, which is conducive to improving the test accuracy; the d _min = 40mm, the d = 80mm can better meet the accuracy requirements, and save the time of measurement; the present invention uses the integration principle to determine the agitator Overall flow rate, the measurement method of the overall flow rate of the mixer is given, and a test bench for measuring the overall flow rate of the submersible mixer is designed to provide accurate experimental data for the factory report of the mixer.

The described embodiment is a preferred implementation of the present invention, but the present invention is not limited to the above-mentioned implementation, without departing from the essence of the present invention, any obvious improvement, replacement or modification that those skilled in the art can make Modifications all belong to the protection scope of the present invention.

Claims (10)

1. measure a test board for the overall flow velocity of submersible agitator, it is characterized in that, comprising: be placed on the submersible agitator (7) in treatment tank (15) and taper five-hole probe (8); The interstitial hole of described submersible agitator (7) impeller central axis and described taper five-hole probe (8) is in same level;

The centre position of described treatment tank (15) wing passage is provided with test board and arranges district T (16), described test board arranges that district T (16) open top both sides are provided with the two track A (1) be parallel to each other, pedal (10) is provided with between two guide rail A (1), described pedal (10) can move forward and backward along guide rail A (1), the centre position, bottom of described test section (15) is vertically fixed with track B (4), and described track B (4) is vertically fixed with bracket (9);

Described submersible agitator (7) is placed on described bracket (9); Described submersible agitator (7) is connected by cable (5) with switch board (14);

Described taper five-hole probe (8) is fixedly connected with fixed support (2), described fixed support (2) slides with guide rail C (11) and links, described fixed support (2) can move left and right along described guide rail C (11), described guide rail C (11) and described pedal (10) fixed-link; Described taper five-hole probe (8) is connected by pressure transducer (3) with the input end of signal picker (12), and the output terminal of described signal picker (12) is connected with computing machine (13).

2. a kind of test board measuring the overall flow velocity of submersible agitator according to claim 1, it is characterized in that, described treatment tank (15) is road shape pond.

3. a kind of test board measuring the overall flow velocity of submersible agitator according to claim 1, it is characterized in that, described taper five-hole probe (8) has two at least.

4. a kind of test board measuring the overall flow velocity of submersible agitator according to claim 1, it is characterized in that, described fixed support (2) comprises the groove (201) be connected with described guide rail C (11), described groove (201) is fixed with montant (202) above, described montant (202) is fixed with support arm (203), the end of described support arm (203) is provided with fixture (204), and described taper five-hole probe (8) is fastened by bolts on described fixture (204).

5. a kind of test board measuring the overall flow velocity of submersible agitator according to claim 1, it is characterized in that, the two ends of described guide rail C (11) are by cross bar (1101) and described pedal (10) fixed-link.

6. measure a method for the overall flow velocity of submersible agitator, it is characterized in that, comprise the following steps:

S1, described submersible agitator (7) is installed:

Mention described submersible agitator (7) with hoist cable (6), along described guide rail B (4), described submersible agitator (7) is placed on described bracket (9);

S2, regulate the described position of taper five-hole probe (8) on described fixed support (2):

Make the impeller central axis of the interstitial hole of described taper five-hole probe (8) and described submersible agitator (7) in same level, after centering, described taper five-hole probe (8) is fixed;

S3, regulate the measuring position of described taper five-hole probe (8):

Describedly move left and right described fixed support (2) along described pedal (10), make the described taper five-hole probe (8) on two described fixed supports (2) be in the position of I and symmetry respectively, position has adjusted rear fixing described fixed support (2);

S4, regulate described taper five-hole probe (8) and described submersible agitator (7) distance;

Along the mobile described pedal (10) of described guide rail A (1), make the distance of the top of described taper five-hole probe (8) and described submersible agitator (7) impeller place plane be the n of impeller diameter doubly, fixing described pedal (10);

S5, complete the connection of test board:

Described cable (5) is accessed described switch board (14);

Described taper five-hole probe (8) is connected with described pressure transducer (3), described signal picker (12) and described computing machine (13) successively;

S6, startup submersible agitator (7):

Control described submersible agitator (7) by described switch board (14) at least to operate under rated voltage, rated frequency 20min, flow field is stablized;

S7, reading measurement data:

The mean flow rate of reading displayed symmetrical measurement point on described computing machine (13), from minimum diameter d _minplace starts to measure, and makes described fixed support (2) drive described taper five-hole probe (8) to move to two ends, until measured mean flow rate drops to lower than V along the pointwise of described guide rail C (11) with the diameter increment of every d _mintime till, then determine circle maximum diameter d _max;

S8, integral principle is utilized to measure the overall flow velocity of described submersible agitator (7):

$Q=Q_{\min }+Q_{I-\mathrm{II}}+...+Q_{(N-1)-N}=\frac{\stackrel{\&OverBar;}{V_I}{\mathrm{\&pi;d}}_{\min }^2}{4}+\frac{\stackrel{\&OverBar;}{V_{\mathrm{II}}}\mathrm{\&pi;}(d_{\mathrm{II}}^2-d_I^2)}{4}+...+\frac{\stackrel{\&OverBar;}{V_N}\mathrm{\&pi;}(d_N^2-d_{N-1}^2)}{4}$

$V_{\mathrm{av}}=\frac{4Q}{\mathrm{\&pi;}{d}_{\max }^2}$

In formula, Q _minfor inner circle flow, Q _i-IIbe the annulus flow of I-II, Q _(N-1)-Nfor the annulus flow of (N-1)-N, be the mean value of I two ends flow velocity, be the mean value of II two ends flow velocity, for the mean value of N two ends flow velocity, d _minfor the minimum diameter of circle, d _ibe I place diameter of a circle, d _nfor N place diameter of a circle, π is constant, V _avfor overall flow velocity, d _maxfor the maximum gauge of circle.

7. a kind of method measuring the overall flow velocity of submersible agitator according to claim 6, it is characterized in that, also comprising minimum flow velocity is V _mindetermining step: to described submersible agitator (7) UG three-dimensional modeling, put into the pipe of 1.12 times of impeller diameters, extract water body, the large-scale grid software grid division of ICEM, utilizes CFD software to carry out numerical simulation to water body, works as Q _m=(1 ~ 1.05) Q _ttime, wherein Q _mfor simulating the flow of gained, Q _tfor testing the flow recorded, minimum flow velocity is V _min=0.105 ~ 0.114m/s.

8. a kind of method measuring the overall flow velocity of submersible agitator according to claim 7, is characterized in that, described minimum flow velocity V _min=0.11m/s.

9. a kind of method measuring the overall flow velocity of submersible agitator according to claim 6, it is characterized in that, n=3 in described S4, the top of described taper five-hole probe (8) and the distance of described submersible agitator (7) impeller place plane are 3 times of impeller diameter, i.e. L=3 × Φ d.

10. a kind of method measuring the overall flow velocity of submersible agitator according to claim 6, is characterized in that, described d _min=40mm, described d=80mm.