JPH06182194A - Device for producing stream of fine particle - Google Patents

Abstract

PURPOSE:To produce a uniform and stable fine particle stream for a long period of time by a method where a plurality of gas introducing openings are provided in the tangential directions and located in a plurality of vertical positions of a generation chamber and a separate gas adjusting valve is provided for each gas introducing pipe. CONSTITUTION:Since gas introducing openings 5, 5a and 5b are oriented tangentially in a generation chamber 1, air introduced to the chamber 1 through a gas introducing pipe 3 is moved upwardly in a revolving stream in the generation chamber while raising the fine particles. The fine particles are mixed in the air and carried out of the generation chamber 1 through a discharge pipe 6. To adjust the amt. of the fine particles mixed in the air, adjusting valves 7, 7a and 7b are adjusted to regulate the amt. of the air being introduced in the chamber thereby a uniform and stable stream of the raised particles therein can be produced for a long period of time. Also, the revolving stream can be adjusted to produce a stable fine particle stream of a desired density.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for a laser Doppler velocimeter or a laser light sheet for measuring gas flow (flow velocity and direction) by observing scattered light of fine particles moving along with gas flow. And a particulate flow generator.

[0002]

2. Description of the Related Art Fine particles (several μm to 100 μm) used for laser Doppler velocimeter and laser light sheet
As a generator of the above, it has a double-structured duct inserted in a powder fluid container, a nozzle is provided between the first and second ducts, and a suction nozzle is provided at the tip of the second duct. Powder suction means for sucking the powder in the powder container through the suction nozzle by the negative pressure caused by the movement of the compressed air supplied to the second duct (JP-A-62-233738).
Is known.

[0003]

However, in the above-mentioned device, since the particles are sucked from the suction nozzle by using the negative pressure, it is difficult to suck the particles on a flat surface, and the portion near the nozzle is difficult to suck. Since a concave portion is formed, a uniform fine particle flow cannot be generated for a long time. Further, in the known example, since the positional relationship with the suction nozzle is controlled according to the change of the powder level, this control technique is actually very difficult, and the apparatus becomes complicated and expensive.

An object of the present invention is to provide a particle flow generator capable of stably generating a uniform particle flow for a long time.

[0005]

The structure of the particle flow generator according to the present invention is as follows.

The fine particle flow generation chamber is formed in a cylindrical shape, and the fine particles are contained in the bottom of the generation chamber. The gas introduction port for the generation chamber is attached tangentially, and the gas introduction port is located above and below the generation chamber. A fine particle flow generator characterized in that it is arranged at a plurality of positions in the direction, a gas adjusting valve is attached to each of the gas introducing pipes reaching the gas introducing port, and a fine particle flow outlet pipe is attached to the upper part of the generating chamber. .

[0007]

In the bottom of the generating chamber, fine particles having a uniform particle size are contained, and pressurized gas such as air is introduced from a plurality of upper and lower positions in the generating chamber through the gas introducing pipe. The introduced gas has its gas inlet directed tangentially in the generation chamber, so it is ejected in the tangential direction and rises above the generation chamber where the pressure is low while creating a swirling flow in the generation chamber. increase. The fine particles that have been thrown in are mixed in the gas, and are guided out of the generation chamber via the fine particle discharge pipe.
It is sent to the room to be measured or inside the container.

Since the mixing amount of the fine particles is determined by the flow velocity of the gas introduced into the generation chamber, by adjusting the mixing valve with a control valve, a uniform circulating flow can be stably formed in the generation chamber.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, 1 is a cylindrical generating chamber, 2 is fine particles contained in the bottom of the generating chamber 1, 3 is a gas introducing pipe, and this gas introducing pipe 3 is a branch pipe 4. 4a, 4
It is branched at b and is connected to the gas introduction ports 5, 5a, 5b which are formed above the fine particles 2 in the tangential direction in the generation chamber 1 and are arranged vertically.

The reference numeral 6 designates a fine particle flow outlet pipe with a control valve 8 extending from the center of the upper portion of the generation chamber 1, and this tip is connected to the chamber to be measured.

Reference numerals 7, 7a and 7b are control valves attached to the branch pipes 4, 4a and 4b, respectively.

In the above embodiment, the air introduced from the gas introduction pipe 3 is jetted into the generation chamber 1 from the branch pipes 4, 4a, 4b via the gas introduction ports 5, 5a, 5b. At this time, since the gas inlets 5, 5a, 5b are oriented tangentially in the generation chamber 1, the fluidized gas becomes a swirling flow and rises while swirling in the generation chamber 1, and the fine particles are scattered during this period. increase. The fine particles that have been thrown in are mixed in the gas,
It is led out of the generation chamber 1 from the lead-out pipe 6. When adjusting the mixing amount of fine particles in the derived fine particle flow, the control valves 7, 7a, 7b are adjusted to adjust the gas introduction port 5,
The amount of gas introduced into the generation chamber 1 from 5a and 5b is adjusted. In addition, in the case of the above-mentioned embodiment, the gas introduction ports are provided at three places, but it may be provided at two places.

[0013]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, the fine particles are contained in the bottom of the generation chamber, and the swirling flow of gas is generated above and below the generation chamber to raise the fine particles inside and to generate a uniform fine particle flow for a long time. It can be generated stably. Further, according to the present invention, since the swirling flow is generated only by providing the gas inlet in the generation chamber in the tangential direction, the structure of the generator is extremely simple and can be downsized, and can be provided at low cost. . In addition, by providing a plurality of gas inlets in the vertical direction of the generation chamber and adjusting the amount of gas ejected from the gas inlets with a control valve, the swirling flow is adjusted to stabilize a fine particle flow of any density. Can be generated.

[Brief description of drawings]

FIG. 1 is a perspective view of a generator according to the present invention.

FIG. 2 is a sectional view of a generation chamber showing a positional relationship of gas inlets.

[Explanation of Codes] 1 Generation chamber 2 Fine particles 3 Gas introduction pipe 4, 4a, 4b Branch pipe 5, 5a, 5b Gas introduction port 6 Fine particle flow discharge pipe 7, 7a, 7b Control valve 8 Control valve

Claims (1)

[Claims] 1. A fine particle flow generation chamber is formed in a cylindrical shape and fine particles are contained in the bottom of the generation chamber, and a gas introduction port for the generation chamber is attached tangentially and the gas introduction port is generated. The fine particle flow is characterized in that a plurality of locations are arranged in the vertical direction of the room, a gas regulating valve is attached to each of the gas introduction pipes reaching the gas introduction port, and a fine particle flow outlet pipe is attached to the upper part of the generation chamber. Generator.