JPS595955A - Apparatus for generating particulate - Google Patents

Abstract

PURPOSE:To obtain an apparatus capable of generating a particulate (a fine granular substance such as soot) without heating at a high temp., by utilizing a diffused flame. CONSTITUTION:HC fuel such as C3H8 is supplied in a definite amount slightly excessive as compared to the supply amount of air from a fuel supply port 11 and air is supplied in a definite amount from an air supply port 12 while dry air is supplied in a definite amount from a dry air injection port 7. When the fuel is injected from a nozzle 9 to be ignited while air is blown out from an air blow-out port 10, a diffused flame is formed. Because the fuel is supplied in an amount slightly excessive as compared to the supply amount of air, a particulate is generated in a combustion chamber 1. The generated particulate is taken out while diluted with dry air at an outlet 6. Because the diffused flame is uilized, it is sufficient to carry out temp. conditioning to an extent preventing the dewing of moisture unless fuel and air are heated to a temp. of several hundred degree on the order of 1,000 deg.C and handling becomes easy.

Description

[Detailed description of the invention] The present invention relates to a particulate generator.

Particulate here means fine particulate matter such as soot.

For example, particulate-free continuous measuring devices that utilize photoacoustic effects have recently been used to measure soot substances in automobile exhaust gas in real time.

Such devices are described in numerous publications such as Japanese Patent Application Laid-Open No. 51-46182. For calibration to improve the reliability and accuracy of measured values in such measuring devices,
Alternatively, particulates having a certain concentration are required in order to determine in advance an appropriate stopping frequency.

Conventional particulate generators generate particulate 'ir' by heating a smaller amount of air together with fuel to a high temperature of several hundred degrees.
There is a method that allows this to occur, but it has the disadvantage that it is difficult to handle because it must be heated to a high temperature.

The present invention provides a new device that can generate a constant amount of particulates by utilizing a diffusion flame without heating to a high temperature as in the past.

An embodiment of the present invention will be described below based on the drawings. 1st
The figure is a sectional view showing a combustion chamber of a particulate generator, and the combustion chamber 1 is formed by joining a lower block 2 and an upper block 3. The combustion chamber 1 is open only at the top, and a pipe 5 bent in an arc shape is connected to the opening 4 to form a particulate outlet 6. The particulate outlet 6 is enclosed in a jacket tube 8 having a dry air injection lower part. In the combustion chamber 1, a fuel injection nozzle 9 is provided in an upright position at the center of the lower block 2, and around the nozzle 9, air blow-off ports 1O... are provided. The nozzle 9 communicates with a fuel supply port 11 formed on the bottom surface of the lower block 2, and -
The air outlet ports 10 communicate with an air supply port 12 formed on the side of the lower block 2. In addition to the above, an ignition section 13 is also provided within the combustion chamber 1. A high voltage HV is applied to the ignition section 13 from the outside through the side of the upper block 3, and ignition is performed by an arc generated between the ignition section 13 and the nozzle 9. A combustion chamber monitoring window 14 is provided on the side of the upper block 3 above the ignition part 13.
The flame can be monitored from the outside through the fiber 15'jj. In the same figure, the entire upper block 3 and the vibrator 5 u loo are surrounded by broken lines in the figure.

The temperature is controlled to above C. This is to prevent moisture in the particulate generated gas from condensing.

The fuel supply port 11. Piping as shown in FIG. 2 is connected to the air supply port 12 and the dry air injection lower. That is, the fuel supply port 11 has a pipe 16 for supplying a fixed amount of HC fuel such as C3H5 as fuel in excess of the air supply amount described later, and the air supply port 12 has a pipe 17 for supplying a fixed amount of air. Further, piping 18 for supplying a fixed amount of dry air is connected to each of the dry air injection lowers. Pipes 16 and 17 are connected to on-off valves 19 and 20, and differential pressure valve 21°2, respectively.
2. It has a configuration in which 5 m of capillaries are connected in series, and fuel and air are supplied in fixed amounts by the action of the capillaries 23 and 24. Each capillary 23.24
A series circuit of a regulating valve 25, 26 and a capillary 27, 28 is connected in parallel to each of the terminals. Regulating valve 25.2
6 is closed during operation, but opens only when igniting. This is because the flow rate ratio of fuel and air at the time of ignition is different from that during operation, so it is necessary to adjust the flow rate ratio at the time of ignition. The pipe 18 is branched from the middle of the pipe 17. A capillary 29 is also provided in this pipe 1B to supply a fixed amount of dry air to the dry air injection lower. Since the air source for pipes 18 and 17 is common, dry air is used as the air source.

According to the above configuration, when fuel is ejected from the nozzle 9 and ignited with air being blown out from the air outlet lO around the fuel, a so-called diffusion flame is generated above the nozzle 9. Since the fuel is slightly in excess of the amount of air supplied, particulates are generated in the combustion chamber 1.The amount of particulates generated is always constant because both fuel and air are supplied in fixed amounts. (Thus, the particulates are diluted with a certain amount of dry air at the outlet 6 and taken out.The reason why dry air was used to dilute the particulates is to prevent moisture from condensing.) Diffusion flame generally refers to a combustion state where air is supplied from around the center of the gas blowing out, as in the case of burning a candle.Then, by using this diffusion flame, In order to generate particulates If at a constant rate, it is necessary to eject the fuel from the nozzle 9 in a laminar flow state.In this embodiment, the volume of the combustion chamber l is '5!: 15c.
approximately 20 CC/ma using C8H as fuel.
By supplying 500 CC of air and 7 mL of air, the fuel is ejected in a laminar flow state and a diffusion flame is created.
We were able to generate a certain amount of particulates.

As explained above, the particulate generator according to the present invention includes a combustion chamber having a particulate outlet,
A fuel injection nozzle provided in the combustion chamber, an air outlet provided in the combustion chamber around the nozzle, a dry air inlet provided in the particulate outlet portion, and the air outlet. a pipe for supplying a constant amount of air to the nozzle, a pipe for supplying a constant amount of fuel to the nozzle in excess of the amount of air supplied, and a pipe for supplying a constant amount of dry air to the dry air inlet. Because of this, it has the following effects:

■ A certain amount of fuel, which is slightly in excess of the amount of air supplied, is ejected from the nozzle at a constant rate, and a certain amount of air is supplied from around it, so a diffusion flame can be created at the nozzle position, and the diffusion flame can eject a certain amount of particulates. can be generated stably.

■ Since particulates are generated using a diffusion flame, the temperature can be controlled to a level that prevents condensation of heat and moisture without having to heat the fuel and air to high temperatures of tens of hundreds of degrees as in conventional methods. All you have to do is just do it, so it is easy to handle.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which Fig. 1 is a side sectional view showing the configuration of a combustion chamber, and Fig. 2 is a piping diagram for supplying fuel, air, and dry air. ■... Combustion chamber, 6... Particulate outlet, 7
...Dry air inlet, 9...Fuel injection nozzle, l
O...Air outlet, 16...Fuel supply pipe, 17.
...Air supply piping, 18...Dry air supply piping. (7) Figure 1

Claims (1)

[Claims] a combustion chamber having a particulate outlet; a fuel injection nozzle provided within the combustion chamber; an air outlet provided within the combustion chamber and around the nozzle; A dry air inlet, a pipe for supplying a fixed amount of air to the air outlet, a pipe for supplying a fixed amount of fuel to the nozzle in excess of the air supply amount, and a pipe for supplying dry air to the dry air inlet. A particulate generation device comprising piping that supplies a fixed amount.