JPH06346807A - Carburetor - Google Patents

Abstract

PURPOSE:To provide the carburetor of a reforming system for an internal combustion engine, in which most of heat energy in heat source is used as vaporized latent heat and constant vaporized amount and vaporized speed are obtained at all times regardless of an automobile running mode. CONSTITUTION:A rotor 27 provided rotatably through a supporting leg 26 on the inner wall surface of a housing 25 whose inner part is used as an exhaust gas flow passage, is rotated with high speed by receiving dynamic pressure of exhaust gas by a fan 31. An inner pipe 34 is fix-arranged in stationary condition at intervals for a fuel flow passage 36 in the inside of the cylindrical outer pipe 28 in the major part of the rotor 27. Mixture liquid fuel (methanol + water) led in through a liquid fuel pipe 39 passes in a combustion chamber 43 and a fuel passing port 41 provided on the one end inside of an inner pipe, and then supplied into the fuel flow passage 36. At this time, liquid fuel becomes in thin film condition by taking centrifugal force generated by an outer cylinder which is rotated with high speed, and then it is gasified by taking latent heat from exhaust gas which flows on the outer side of the outer cylinder. Gasified fuel steam passes through a fuel passing port 42 and a fuel chamber 44, and it is led out through a fuel steam pipe 40.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to vaporizers, and more particularly to vaporizers used to vaporize liquid fuel prior to reforming reactions in automotive fuel reformers.

[0002]

2. Description of the Related Art An example of an automobile fuel reformer is disclosed in Japanese Patent Laid-Open No.
No. 0-51602. This reformer is for vaporizing a liquid fuel mainly composed of alcohol such as methanol, and for reforming the fuel gas vaporized through the vaporizing portion into a hydrogen-rich gas by the action of a reforming catalyst. And a reforming reaction part of. Exhaust gas from an internal combustion engine is used as a heat source required for the vaporization and reforming reaction.

[0003]

In the vaporizing section of such a conventional reformer, the liquid fuel 2 filled in the tubes or between the plates obtains latent heat from the exhaust gas flowing outside the tubes or the plates. Be vaporized.

However, there is a problem that sufficient heat transfer efficiency cannot be obtained because the contact area between the exhaust gas and the outer surface of the tube or plate forming the flow path of the liquid fuel is small. In order to increase the heat transfer efficiency, it is conceivable to elongate the vaporization flow path or increase the flow velocity of the exhaust gas, but this is not preferable because it causes an increase in the size, complexity, and cost of the device.

Further, in the on-vehicle reformer, the liquid level of the liquid fuel constantly fluctuates according to the running condition of the automobile, so that the contact area with the exhaust gas fluctuates, and a constant vaporization amount and vaporization speed are maintained. I can't get it.

Further, since the liquid fuel supplied at room temperature is rapidly heated by the high temperature exhaust gas, the liquid fuel is likely to cause bumping in the flow path. This not only reduces the heat transfer efficiency, but when the reforming reaction section is provided above the vaporization section, the blown fuel contaminates the surface of the reforming catalyst and deteriorates the catalyst.

Further, the heat energy obtained from the exhaust gas is consumed not only as the latent heat of vaporization but also as the temperature rise (sensible heat) of the liquid fuel. In the conventional structure as described above, the liquid fuel is consumed. Most of the thermal energy of the exhaust gas is consumed as sensible heat because heat is transferred only in the extremely thin boundary layer formed between the heat transfer surface and the heat transfer surface (inner surface of the tube or plate 1). There was a big problem that a sufficient latent heat of vaporization could not be obtained.

[0008]

The present invention solves the above-mentioned problems in conventional vaporizers, has excellent heat transfer efficiency, and is capable of performing stable vaporization at all times during vehicle operation even when used in a vehicle. An object is to provide a vaporizer.

A vaporizer according to the present invention, which was devised to achieve the above object, is provided with a heat source gas passage for flowing the heat source gas in a predetermined direction, and is rotated by the dynamic pressure of the heat source gas provided in the heat source gas passage. A cylindrical rotating body, a stationary body provided inside the rotating body, a liquid introduction path connected to one end of the liquid flow path formed between the rotating body and the stationary body, and a liquid flow path The other end has a steam lead-out passage connected to the other end.

The liquid introduced from the liquid introduction passage to the liquid passage is subjected to centrifugal force due to the rotation of the rotating body to be heat-transfer vaporized by the heat source gas in a thin film state, and is led out from the vapor lead-out passage as vapor. .

The heat source gas flow passage can be formed in a cylindrical or box-shaped housing. In this case, the rotating body is
The rotating body is rotatably supported by the support legs attached to the inner wall surface of the housing.

The rotating body can be rotated by providing the rotating body with a fan and receiving the dynamic pressure of the heat source gas flowing through the heat source gas passage.

In this case, it is preferable that the portion of the rotating body in front of the fan has an inclined surface that converges in the direction of the heat source gas inlet of the heat source gas passage.

Preferably, the stationary body is formed in a tubular shape.
At both inner ends of the cylindrical stationary body, a first chamber is connected between the liquid introduction path and the liquid flow path, and a first chamber connected between them is connected between the vapor discharge path and the liquid flow path. A second chamber can be formed. It is preferable that a cavity be provided between the first and second chambers.

Flow control means may be provided for the flow of the heat source gas in the heat source gas channel and the flow of the liquid in the liquid channel.

The vaporizer according to the present invention is preferably used in a reforming system for an automobile internal combustion engine, which reforms vaporized liquid fuel by the action of a reforming catalyst and then supplies the reformed catalyst to the internal combustion engine of the automobile. In this case, it is preferable to provide a control means for controlling the flow rate of the liquid fuel to the liquid introduction passage according to the rotation speed of the internal combustion engine.

[0017]

[Operation] The liquid introduced from the liquid introduction passage to the liquid passage is
The heat source gas is vaporized by the heat source gas in the state of being thinned by the centrifugal force generated by the rotation of the rotating body. Therefore, it is substantially prevented that the heat energy of the heat source gas is wastefully consumed as sensible heat for causing the temperature rise of the liquid itself,
Since most of it is used as latent heat of vaporization, it has excellent heat transfer efficiency and efficient vaporization.

[0018]

1 shows the structure of a vaporizer (vaporizer) according to an embodiment of the present invention used in the automobile reforming system shown in FIG.

First, referring to the system diagram of FIG. 2, the alcohol fuel 11 such as methanol in the fuel tank 10 is pumped by the pump 12, and the deionized water 15 in the water tank 14 is pumped by the pump 16 in the lines 13, 17 respectively. Is supplied to the vaporizer 18 as a mixed liquid fuel. Pump 12,
The flow rate of 16 is controlled by the controller 19.
A signal indicating the rotation speed is input from the internal combustion engine 20 to the controller 19, and the flow rates of the alcohol fuel 11 and the pure water 15 are controlled according to the rotation speed. Therefore, the vaporizer 1
8 is always supplied with an appropriate amount of mixed liquid fuel.

The mixed liquid fuel is vaporized by the vaporizer 18 into a fuel gas, which is sent to the reformer 21. The fuel gas is reformed into hydrogen-rich gas by the action of the catalyst while passing through the reforming catalyst filling portion of the reformer 21, and is sent to the internal combustion engine 20 through the line 22. Further, gasoline fuel is supplied to the internal combustion engine 20 through a line 24.

The exhaust gas discharged from the internal combustion engine 20 is
As a heat source gas that is supplied to the vaporizer 18 and the reformer 21 via the line 23 and that provides the heat quantity necessary for vaporizing the mixed liquid fuel in the vaporizer 18 and the reforming reaction of the fuel gas in the reformer 21. After being used, it is discharged out of the system.

The structure of the vaporizer 18 used in the above system is shown in FIG. The carburetor 18 has a tubular or box-shaped housing 25 that communicates with an exhaust gas supply line 24. That is, the exhaust gas supplied through the line 24 is introduced into the housing 25 as a high-speed airflow from one end 25a and the other end 25b as shown by the arrow.
Emitted from.

Inside the housing 25, the housing 2
A rotary body 27 rotatably supported by a plurality of support legs 26 is provided on the inner wall surface of 5. A main part of the rotating body 27 is an outer tube 28 having a hollow cylindrical shape, and a spiral fin 29 protruding toward the exhaust gas flow path is provided on the outer wall surface of the outer tube 28.
Is provided. The front portion 30 of the rotating body 27 has a fan 31 for rotating the rotating body 27 as described later.
And a hollow shaft 32 for inserting a fuel vapor pipe 40 described later. The outer wall surface of the portion in front of the fan 31 has an inclined surface 33 that converges toward the exhaust gas inlet 25a.
It is said that.

An inner pipe 34 is fixedly provided inside the outer pipe 28. A spacer 35 is attached to the outer wall surface of the inner tube 34, and the outer periphery of the spacer 35 is in liquid-tight contact with the inner wall surface of the outer tube 28 in a relatively rotatable manner. Therefore,
A space corresponding to the thickness of the spacer 35 is provided between the inner wall surface of the outer pipe 28 and the outer wall surface of the inner pipe 34, and
It is assumed to be 6. On the outer wall surface of the inner pipe 34, spiral fins 37 projecting toward the fuel flow path 36 are provided.

The inner tube 34 is provided with two partition walls 381 and 382 that liquid-tightly close the inner space thereof. As a result, a space is formed between the partition walls 381 and 382, and the weight of the entire device is reduced.

At one end of the inner pipe 34, the lines 13 and 1
Alcohol fuel 11 and pure water 15 supplied from 7
(See FIG. 2) is connected to a liquid fuel pipe 39 for introducing a mixed liquid fuel, and at the other end, fuel vapor for supplying vaporized fuel to the reformer 21 (FIG. 2). The pipe 40 is connected. Since the liquid fuel expands in volume by vaporization, the diameter of the fuel vapor pipe 40 is larger than that of the liquid fuel pipe 39.

Fuel passage ports 41 and 42 are formed in the wall surface of the inner pipe 34 at the end sides of the partition walls 381 and 382, respectively, and the fuel chambers 43 and 4 inside the inner pipe 34 are formed.
4 and the fuel flow path 36 are circulated.

In the carburetor 18 constructed as described above, the exhaust gas supplied through the exhaust gas supply line 24 enters the housing 25 through the exhaust gas inlet 25a.
At this time, the dynamic pressure of exhaust gas in the housing 25 is set to the fan 3
The rotating body 27 is rotated by the 1 being received. The high-speed exhaust gas flow is further accelerated by the inclined surface 33 in the front portion 30 of the rotating body 27, and the exhaust gas dynamic pressure is efficiently converted into rotational force by the fan 31. Thus, the outer tube 28 also integrally rotates at high speed. Exhaust gas is fan 3
After rotating 1, the fluid flows in the housing 25 while coming into contact with the outer wall surface of the outer pipe 28, and is discharged from the exhaust gas outlet 25b.

On the other hand, the mixed liquid fuel supplied through the liquid fuel pipe 39 first enters the fuel chamber 43 in the inner pipe 34, passes through the fuel passage port 41, and is between the outer pipe 28 and the inner pipe 34. It enters the fuel flow path 36 to be formed. As described above, the outer pipe 28 is rotating at high speed due to the wind pressure of the exhaust gas,
Centrifugal force acts on the mixed liquid fuel filled in the fuel flow path 36 to form a thin film along the inner wall surface of the outer pipe 28. By making the fuel into a thin film in this manner, the latent heat of vaporization by the high-temperature exhaust gas flowing while being in contact with the outer wall surface of the outer pipe 28 is efficiently received.

The vaporized fuel enters the fuel chamber 44 from the fuel flow path 36 through the fuel passage port 42, and is further sent to the reformer 21 by the fuel vapor pipe 40.

Fins 29 provided toward the exhaust gas flow path and fins 37 provided toward the fuel flow path 36.
Respectively act as rectifying means for smoothing the flow of exhaust gas and fuel fluid.

The carburetor 18 of the illustrated embodiment is a housing 2
5, rotating body 27 including outer pipe 28, inner cylinder 34, pipe 3
9 and 40 are all made of SUS. Pipes 39 and 4
0 is provided with spiral portions 45 and 46, respectively, in order to play or escape the thermal expansion of SUS by the fluid flowing inside.

[0033]

According to the present invention, heat is exchanged with the heat source gas in a fluidized state in which the liquid is made into a thin film, and most of the heat energy of the heat source gas can be used as latent heat of vaporization, which is extremely excellent. Excellent vaporization efficiency can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing a configuration of a vaporizer according to an embodiment of the present invention.

2 is a system configuration diagram showing a reforming system for an automobile internal combustion engine including the vaporizer of FIG. 1. FIG.

[Explanation of symbols]

 18 vaporizer 19 controller 20 internal combustion engine 21 reformer 27 rotating body 28 outer pipe 29 fins 31 fan 34 inner pipe 36 fuel flow path 37 fins 381, 382 partition wall 39 liquid fuel pipe 40 fuel vapor pipe 43, 44 fuel chamber

Claims (10)

[Claims] 1. A heat source gas flow passage for flowing a heat source gas in a predetermined direction, a cylindrical rotary member provided in the heat source gas flow passage and rotated by a dynamic pressure of the heat source gas, and inside the rotary member. A stationary body provided, a liquid introduction path communicating with one end of a liquid flow path formed between the rotating body and the stationary body, and a vapor derivation path communicating with the other end of the liquid flow path. The liquid introduced into the liquid flow path from the liquid introduction path is subjected to centrifugal force due to the rotation of the rotating body to be heat-transferred by the heat source gas in a thin film state,
A vaporizer which is discharged as steam from the steam discharge path. 2. The heat source gas flow path is formed in a cylindrical or box-shaped housing, and the rotating body is rotatably supported by support legs attached to an inner wall surface of the housing. Item 1 vaporizer. 3. The vaporizer according to claim 1, wherein the rotating body is provided with a fan, and the fan receives the dynamic pressure of the heat source gas flowing in the heat source gas passage to rotate the rotating body. . 4. The vaporizer according to claim 3, wherein a portion of the rotary body in front of the fan has an inclined surface which converges in a heat source gas inlet direction of the heat source gas passage. 5. The vaporizer according to claim 1, wherein the stationary body is formed in a cylindrical shape. 6. A first and a second chamber are formed at both inner ends of the tubular stationary body, and the first chamber is connected to and connected to the liquid introducing passage and the liquid passage. At the same time, the vaporization device according to claim 5, wherein the second chamber is connected to and communicates with the vapor outlet passage and the liquid passage. 7. The vaporizer according to claim 6, wherein a space is provided between the first and second chambers. 8. The vaporizer according to claim 1, further comprising rectifying means for the flow of the heat source gas in the heat source gas passage. 9. The rectifying means for the flow of liquid in the liquid flow path is provided.
Vaporizer. 10. A liquid fuel for use in a reforming system for an internal combustion engine of an automobile, which reforms vaporized liquid fuel by the action of a reforming catalyst and supplies the reformed catalyst to an internal combustion engine of an automobile, the liquid fuel for the liquid introducing passage. 2. The vaporizer according to claim 1, wherein the flow rate of the gas is controlled according to the rotational speed of the internal combustion engine.