Tracer particle generating device for LDV measurement

Abstract

The utility model discloses a tracer particle generating device for LDV measurement, which comprises a box body, an air injection mechanism is fixed in the box body, the air injection mechanism comprises two transverse pipes, two groups of longitudinal pipes are communicated between the two transverse pipes, a plurality of air holes are arranged on the longitudinal pipes, the two groups of longitudinal pipes and the two transverse pipes are enclosed to form an avoidance hole, and the avoidance hole is communicated with the air holes. At least one atomizer is detachably connected to the lower portion of the receding hole, one transverse pipe is externally connected with an air supply mechanism, the air supply mechanism is used for providing compressed air, and an air outlet channel is formed in the upper end of the box wall of the box body. Compared with the prior art, when the atomizer works, the atomizer generates a large amount of aerial fog, the aerial fog is driven to the upper side from the lower side of the box body through compressed air from the air holes, and then the aerial fog is sent out through the air outlet channel. The particle size of aerial fog particles generated by the device meets the requirement of LDV on the particle size of tracer particles, and the measurement requirement is met. Secondly, the aerial fog particles are free of any other pollutants. And thirdly, an avoiding hole is formed, so that the atomizer is convenient to mount.

Description

Technical Field

[0001] The utility model relates to the technical field of tracer particle manufacturing, in particular to a tracer particle generating device for LDV measurement. Background Art

[0002] The Laser Doppler Velocimeter (LDV) is essentially an instrument that uses the scattered light of tiny particles in the fluid that move at the same speed as the fluid to measure the fluid velocity. Currently, the use of LDV for wind speed measurement is a hot topic in research and application. Tracer particle velocimetry technology is used to characterize wind speed, that is, the movement of tracer particles in the wind tunnel measurement section is used to characterize the standard wind speed in the calibration process. It is required that the tracer particles must be able to suspend in the wind tunnel flow field and perfectly flow with a uniform velocity field. Then the measured particle movement speed can be considered as the airflow velocity at the location of the particles. At present, commonly used tracer particles include hollow glass balls, smoke, and bubbles, which have the following shortcomings:

[0003] First, hollow glass balls are suitable for water medium measurement. Their density is close to that of water and much greater than that of air, so they do not have tracking properties.

[0004] Second, the smoke is produced by a smoke generator using high-temperature atomization of smoke oil, and its particle size is small, which cannot be properly identified by LDV during the experiment.

[0005] Third, bubbles are generated by a bubble generator using a diluted surfactant. While their density is close to that of air, they provide good tracking performance. However, their particle concentration is insufficient, preventing them from generating sufficient signal strength at flow rates exceeding 20 m / s. Furthermore, after rupturing within the duct, the bubbles adhere to the inner wall, creating a certain degree of stickiness that makes them difficult to clean and potentially affecting the internal flow field. Utility Model Content

[0006] The utility model provides a tracer particle generating device for LDV measurement, which is used to solve the problem that existing tracer particles are insufficient in LDV measurement.

[0007] The utility model provides a tracer particle generating device for LDV measurement, comprising a box body, wherein an air jet mechanism is fixed in the box body, wherein the air jet mechanism comprises two transverse tubes, two groups of longitudinal tubes are connected between the two transverse tubes, a plurality of air holes are provided on the longitudinal tubes, and the two groups of longitudinal tubes and the two transverse tubes are enclosed to form an avoidance hole, at least one atomizer is detachably connected below the avoidance hole, an air supply mechanism is externally connected to one of the transverse tubes, and the air supply mechanism is used to provide compressed gas, and an air outlet channel is provided at the upper end of the box wall of the box body.

[0008] Preferably, the aperture of the transverse tube is larger than the aperture of the longitudinal tube.

[0009] Preferably, the number of longitudinal tubes in each group of longitudinal tubes is three, and the longitudinal tubes in each group of longitudinal tubes are distributed at intervals.

[0010] Preferably, an air supply pipe is provided on the box wall of the box body, and both ends of the air supply pipe are respectively connected to the transverse pipe and the air supply mechanism.

[0011] Preferably, a water supply pipe is provided on the box wall of the box body, and the water supply pipe and the air supply pipe are respectively provided on both sides of the box body.

[0012] Preferably, the air outlet channel and the water supply pipe are respectively arranged on two adjacent box walls of the box body.

[0013] Preferably, a wire hole is provided on the box wall of the box body, and the power cord of the atomizer passes through the wire hole.

[0014] Preferably, the wire hole and the air supply pipe are arranged on the same side, and the wire hole is located below the air supply pipe.

[0015] Preferably, the air outlet channel passes through two box walls of the box body.

[0016] Preferably, a plurality of legs are fixed to the lower end of the box.

[0017] Compared with the existing technology, when the present invention is working, the atomizer produces a large amount of aerosol. The compressed air coming out of the air hole drives the aerosol from the bottom of the box to the top, and then sends it out through the air outlet channel. The particle size of the aerosol particles produced by the present invention meets the LDV requirements for the tracer particle size and meets the measurement requirements. Secondly, the aerosol particles do not contain any other pollutants. Even if they break during the detection process, the particles will not adhere to the inner wall of the pipe for a long time and will not affect the internal flow field and flow rate measurement. Thirdly, the setting of the avoidance hole facilitates the installation of the atomizer, and the detachable connection design can flexibly configure the number of atomizers, thereby controlling the amount of aerosol generated to meet the needs of different flow rate measurements. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 It is a structural diagram of the utility model;

[0020] Figure 2 It is a left view of the utility model;

[0021] Figure 3 It is a right side view of the utility model;

[0022] Figure 4 This is a structural diagram of the jet mechanism of the utility model;

[0023] Figure 5 This is a schematic structural diagram of the longitudinal tube of the present utility model;

[0024] Figure 6 This is a partial physical diagram of the utility model.

[0025] Reference numerals:

[0026] 1. Box body, 2. Jet mechanism, 3. Water supply pipe, 4. Wire hole, 5. Support leg, 6. Air supply pipe, 21. Horizontal pipe, 22. Vertical pipe, 221. Air hole, 100. Avoidance hole, 200. Air outlet channel. DETAILED DESCRIPTION

[0027] To make the purpose, technical solutions, and advantages of the present invention more clear, the following will be combined with the accompanying drawings to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0028] Refer to the attached Figure 1 and attached Figure 4The present embodiment provides a tracer particle generating device for LDV measurement, including a box body 1, in which an injection mechanism 2 is fixed, the injection mechanism 2 includes two horizontal tubes 21, two groups of vertical tubes 22 are connected between the two horizontal tubes 21, and a plurality of air holes 221 are provided on the vertical tubes 22. The two groups of vertical tubes 22 and the two horizontal tubes 21 are surrounded by an avoidance hole 100, and at least one atomizer is detachably connected below the avoidance hole 100, and the atomizer is placed at the bottom of the box. An air supply mechanism is externally connected to one horizontal tube 21, and the air supply mechanism is used to provide compressed gas to the vertical tube 22. An air outlet channel 200 is provided at the upper end of the box wall of the box body 1, and an air volume device is provided at the air outlet channel 200. When the present invention is working, water is added to the box body 1, the atomizer is located below the water surface, the jet mechanism 2 is located above the water surface, the atomizer generates a large amount of aerosol, and the compressed air coming out of the air hole 221 drives the aerosol from the bottom of the box body 1 to the top, and the blower matched with the air volume device sucks the aerosol from the air outlet channel 200. The particle size of the aerosol particles generated by the present invention meets the LDV requirements for the particle size of tracer particles. Even at the highest flow rate of 30m / s, the signal intensity still exceeds 100Hz, which meets the measurement requirements. Secondly, the aerosol particles do not contain any other pollutants. Even if they break during the detection process, the particles will not adhere to the inner wall of the pipe for a long time, and will not affect the internal flow field and the measurement of flow rate. Thirdly, the setting of the avoidance hole 100 facilitates the installation of the atomizer, and the detachable connection design can flexibly configure the number of atomizers, thereby controlling the amount of aerosol generated to meet the needs of different flow rate measurements.

[0029] Specifically, the nebulizer is a flat-plate ultrasonic nebulizer, which is an existing product.

[0030] As another embodiment of the present invention: the aperture of the transverse tube 21 is larger than the aperture of the longitudinal tube 22. Specifically, the aperture of the transverse tube 21 is 8 mm, and the aperture of the longitudinal tube 22 is 3 mm.

[0031] As another embodiment of the present invention, the number of longitudinal tubes 22 in each group of longitudinal tubes 22 is three, and the longitudinal tubes 22 in each group of longitudinal tubes 22 are spaced apart. Specifically, in each group of longitudinal tubes 22, the distance between two adjacent longitudinal tubes 22 is 30 mm.

[0032] Specifically, the transverse tube 21 and the longitudinal tube 22 are both made of stainless steel. The transverse tube 21 is fixed to the box body 1 by welding, and the longitudinal tube 22 is connected to the transverse tube 21 by welding.

[0033] For details, please refer to the attached Figure 5 There are 10 air holes 221 on the longitudinal tube 22, and the air outlet directions of the air holes 221 are all upward.

[0034] As another embodiment of the present invention: an air supply pipe 6 is provided on the box wall of the box body 1, and both ends of the air supply pipe 6 are respectively connected to the horizontal pipe 21 and the air supply mechanism.

[0035] As another embodiment of the present invention: Figure 2 A water supply pipe 3 is provided on the wall of the box body 1, and the water supply pipe 3 and the air supply pipe 6 are respectively provided on both sides of the box body 1. Specifically, the water supply pipe 3 and the air supply pipe 6 are symmetrically distributed on both sides of the box body 1.

[0036] As another embodiment of the present invention: the air outlet channel 200 and the water supply pipe 3 are respectively arranged on two adjacent box walls of the box body 1.

[0037] As another embodiment of the present invention: Figure 3 A wire hole 4 is provided on the wall of the box body 1, and the power line of the atomizer passes through the wire hole 4.

[0038] As another embodiment of the present invention: the wire hole 4 and the air supply pipe 6 are arranged on the same side, and the wire hole 4 is located below the air supply pipe 6. Through this structural design, it is adapted to the positional relationship of the atomizer being located below the jet mechanism 2.

[0039] As another embodiment of the present invention: the air outlet channel 200 passes through the two box walls of the box body 1.

[0040] As another embodiment of the present invention: a plurality of legs 5 are fixed to the lower end of the box body 1, and the height of the air outlet channel 200 is adjusted by the legs 5 so that the air outlet channel 200 matches the air volume device.

[0041] Specifically, the box body 1 is a square structure, made of stainless steel, and is welded from a plurality of steel plates, with a box wall thickness of 2 mm.

[0042] In the utility model, water is injected into the box body 1 through the water supply pipe 3, the atomizer is submerged in the water, and the jet mechanism 2 is above the liquid level. When working, the atomizer generates a large amount of aerosol, and the high-speed compressed air discharged by the air hole 221 is driven from the bottom of the box body 1 to the top. The fan matched with the air volume device sucks the aerosol from the air outlet channel 200 and transports it to the pipeline.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A tracer particle generator for LDV measurement, characterized in that: It includes a box body, in which an injection mechanism is fixed, the injection mechanism includes two horizontal tubes, two groups of vertical tubes are connected between the two horizontal tubes, a plurality of air holes are provided on the vertical tubes, the two groups of vertical tubes and the two horizontal tubes are surrounded to form an avoidance hole, at least one atomizer is detachably connected below the avoidance hole, one of the horizontal tubes is externally connected to an air supply mechanism, the air supply mechanism is used to provide compressed gas, and an air outlet channel is provided at the upper end of the box wall of the box body.

2. The tracer particle generator for LDV measurement according to claim 1, characterized in that: The aperture of the transverse tube is larger than the aperture of the longitudinal tube.

3. The tracer particle generator for LDV measurement according to claim 2, characterized in that: The number of the longitudinal tubes in each group of longitudinal tubes is three, and the longitudinal tubes in each group of longitudinal tubes are distributed at intervals.

4. The tracer particle generator for LDV measurement according to claim 3, characterized in that: An air supply pipe is provided on the box wall of the box body, and both ends of the air supply pipe are respectively connected to the horizontal pipe and the air supply mechanism.

5. The tracer particle generator for LDV measurement according to claim 4, characterized in that: A water supply pipe is provided on the box wall of the box body, and the water supply pipe and the air supply pipe are respectively provided on both sides of the box body.

6. The tracer particle generator for LDV measurement according to claim 5, characterized in that: The air outlet channel and the water supply pipe are respectively arranged on two adjacent box walls of the box body.

7. The tracer particle generator for LDV measurement according to claim 6, characterized in that: A wire hole is provided on the box wall of the box body, and the power wire of the atomizer passes through the wire hole.

8. The tracer particle generator for LDV measurement according to claim 7, characterized in that: The wire hole and the air supply pipe are arranged on the same side, and the wire hole is located below the air supply pipe.

9. The tracer particle generator for LDV measurement according to claim 1, characterized in that: The air outlet channel passes through two box walls of the box body.

10. The tracer particle generator for LDV measurement according to claim 1, characterized in that: A plurality of supporting legs are fixed to the lower end of the box body.

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