KR20040023041A - Muffler in vehicle - Google Patents

Abstract

PURPOSE: A muffler in a vehicle is provided to remove an expensive post-processor by preventing excessive exhaust of carbon, thereby preventing increase in the manufacturing cost. CONSTITUTION: An inlet pipe(12) is installed below the center of a housing(10) formed of a closed section in predetermined shape at a predetermined gap. An exhaust pipe(13) is installed near the center of the housing. An induction pipe(12') is installed above the center of the housing at a predetermined gap. A pair of first and second partitions(11,11') are formed inside the housing, supporting the inlet pipe, the exhaust pipe, and the induction pipe with dividing the whole space into first, second, and third intervals(L1,L2,L3) at a certain ratio. A change in pressure of a muffler(3) is limited within a range of 35-45 psi, thereby smoothly flowing gas in the housing.

Description

Muffler in vehicle

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle silencer, and more particularly, to a vehicle silencer that facilitates the flow of exhaust gas and prevents deposition of unburned particulate matter.

In general, the vehicle generating the exhaust gas is equipped with an exhaust system of the vehicle for discharging the gas burned by the engine to the outside, this exhaust system is an exhaust manifold (Ex) of the engine (E), as shown in FIG. And a plurality of silencers (3) provided on the line (1) to be discharged to the atmosphere in a state of reducing the pressure and noise of the exhaust gas to be discharged to the atmosphere (1).

In addition, a catalytic converter for purifying contaminants such as nitrogen oxides in the exhaust gas may be provided.

Here, the muffler (also referred to as muffler) is a resonance of Helm Holtz with a quadrangular box or cylindrical shape inside the exhaust line 1 in order to reduce noise by reducing the pressure difference of the exhaust gas. Using the principle of to reduce the amount of noise in a specific frequency band according to the volume size.

That is, as shown in FIG. 2, the silencer 3 generally has a quadrangular box or a cylindrical cross section, and the housing 10 having a predetermined capacity is provided in the front and rear of the inlet pipe 12 and the outlet pipe 13, respectively. And a plurality of partitions (11, 11 ') are provided in the housing (11) to divide the internal space, and the guide pipe (12') has a predetermined length in the partitions (11, 11 '). It has a structure that is fixed to penetrate in the longitudinal direction.

Here, the inlet pipe 12 and the discharge pipe 13 are respectively positioned to the upper and lower portions of the housing 10, while the induction pipe 12 'is between the inlet pipe 12 and the discharge pipe 13 It is positioned at intervals.

Accordingly, the silencer 3 is configured to attenuate the exhaust noise by lowering the temperature and pressure of the exhaust gas introduced and discharged during operation of the engine, that is, the exhaust gas discharged when the engine is operated is the front inlet pipe 12. Passing through the induction pipe 12 'installed between the first and second partitions 11 and 11' introduced into the housing 10 of the muffler through the exhaust pipe 13 in a state where the pressure and temperature are lowered. It is to be discharged to the inside.

However, compared with gasoline engines, the exhaust gas characteristics of diesel engines have a high air-fuel ratio, low emissions of carbon monoxide (Co) and hydrocarbons (HC), and high compression ratios, resulting in high noise and vibration and high NOx and sulfur oxides (SOx). ), There is a disadvantage in that a large amount of particulate matter including soot (SMOKE) is discharged while generating a lot of cations.

Here, the particulate matter is a sponge-type carbon particles containing a lot of toxic chemicals, it is a pollutant that has been floating in the air for a long time because the particles of very small size of 0.1㎛ ~ 0.3㎛ is distributed, strong adsorption, small and light.

However, the coal medium P, which is a particulate matter contained in the exhaust gas discharged from the diesel engine, is greatly increased in incomplete combustion, so that the housing in the process of circulating in the silencer 3 as shown in FIG. (11) in the pipe (12, 12 ', 13) and a lot of piles, thus accumulating in the muffler (3), the bullet velocity (P) increases the exhaust gas flow rate during the rapid acceleration of the vehicle is discharged with the exhaust gas There is a problem that the emission of air pollutants is increased rapidly.

Accordingly, in the case of diesel vehicles, an exhaust gas aftertreatment using various methods is installed on the line 1 through which the exhaust gas flows through the silencer 3 to remove the bullet P, which is a pollutant in the exhaust gas. Such a post-processor increases the manufacturing cost of the vehicle when it is installed as expensive equipment, and also has a disadvantage in that it is not easy to install due to large design changes in the layout of the vehicle.

Accordingly, the present invention has been made in view of the above-mentioned matters, and the gas is rapidly accelerated by optimizing the pressure and flow rate distribution of the exhaust gas in the silencer so that the exhaust gas introduced into the silencer flows in the pipe and the housing so that accumulation of shot medium does not occur. The purpose is to prevent excessive emissions of coal media under certain conditions, such as avoiding the use of expensive post-processors, resulting in increased manufacturing costs.

The present invention for achieving the above object, the silencer is provided in a downwardly spaced inlet pipe provided at a predetermined interval with respect to the center of the housing made of a closed cross-section of a predetermined shape, and provided in a position near the center of the housing It consists of a discharge pipe and an induction pipe provided upwardly with a predetermined distance with respect to the center of the housing, while the inside of the housing is provided with a pair of first and second partition walls for supporting the pipe while dividing the entire space at a predetermined ratio. It is characterized by.

1 is a schematic configuration diagram of an exhaust gas exhaust system of a general diesel engine

2 is a block diagram of a conventional silencer

Figure 3 is a state in which particulate matter is formed in the silencer according to the prior art

4 is a block diagram of a silencer according to the present invention

5 is an exhaust gas pressure distribution state diagram of the silencer according to the present invention.

6 is an exhaust gas velocity distribution state diagram of the silencer according to the present invention.

<Description of the symbols for the main parts of the drawings>

1: exhaust gas line 2: after-treatment

3: silencer 10: housing

11,11 ': 1st and 2nd bulkhead 12: inflow pipe

12 ': induction pipe 13: discharge pipe

P: bullet

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

4 is a block diagram of a silencer according to the present invention, the silencer 3 of the present invention has a predetermined distance (K) with respect to the center (O) of the housing 10 made of a closed cross-section of a predetermined shape. A predetermined interval with respect to the inlet pipe 12 provided downward, the discharge pipe 13 provided in a position near the center (O) of the housing 10 and the center (O) of the housing 10 K ') is made up of a guide pipe 12' provided upwards, while the inside of the housing 10 is a pair of supporting the pipes (12, 12 ', 13) while dividing the entire space at a certain ratio First and second partitions 11 and 11 'are provided.

In addition, the inflow pipe 12 forms a bias interval a so as to be located relatively downward while being biased to one side on the center of the cross section of the housing 10, and the discharge pipe 13 is the center of the cross section of the housing 10. A bias interval c is formed so as to be in close proximity to the phase and to be biased in a position opposite to the inlet pipe 12, wherein the guide pipe 12 ′ is relatively biased toward one side on the center of the cross section of the housing 10. It is to form a bias interval (b) as possible.

In addition, the partition ratio of the internal space of the housing 10 is the first gap (L1) to the first partition 11 from the tip portion in which the inlet pipe 12 is introduced, and the space between the first partition 11 The second gap L2 between the second partition 11 'installed and the third gap L3 from the second partition 11' to the end of the housing 10 through which the discharge pipe 13 is discharged. Each of these forms 35%, 20% and 45% of the total spacing (L), respectively.

Hereinafter, the operation of the present invention will be described in detail with reference to the accompanying drawings.

According to the present invention, when the exhaust gas discharged from the engine flows along the line 1 of the exhaust system and enters the silencer 3, that is, the exhaust gas introduced through the inlet pipe 12 of the silencer 3 After the gas is discharged into the first gap L1 of the housing 10, most of the gas flows into the third gap L3, and then, through the induction pipe 12 ′ penetrating between the partition walls 11 and 11 ′. While most of the gas is introduced into the first interval (L1) while being discharged to the second interval (L2), and then some gas is discharged to the second and third intervals (L2, L3) through the discharge pipe 13 again. Most of the gas is discharged out of the atmosphere through the line 3 to the outside.

As described above, the exhaust gas discharged to the outside after passing through the silencer 3 passes through the silencer 3 and is almost discharged to the outside without accumulating the coal medium P contained in the exhaust gas in the housing 10. This is, of course, because the flow rate and pressure distribution of the gas inside the housing 10 sufficiently induces a smooth flow of the gas.

That is, as shown in FIG. 5, the pressure distribution in the housing 10 due to the exhaust gas introduced into the silencer 3 includes the gas having the initial pressure P introduced through the inlet pipe 12. When entering the space in the third gap L3 of (10), the pressure of the introduced gas is lowered to Pa, which is a pressure lower than P, and then the induction pipe penetrating between the partition walls 11 and 11 '( 12 ′), the gas pressure in the second interval L2 is further lowered to Pb, and then flows into the space in the first interval L1, which is lower than the pressure Pa in the third section L3 and the second interval. It is converted into Pc which is a pressure slightly higher than Pb which is the gas pressure in (L2).

Subsequently, the gas in the first section L1 is discharged through the line 1 communicating with the atmosphere while gradually decreasing to the pressures Pd and Pe while flowing through the discharge pipe 13.

At this time, P is in the range of about 80-95psi, Pa is about 75-80psi, Pb is about 40-45psi, Pc is about 50-55psi, Pd is about 35-40psi and Pe is less than 5psi Will have

As such, the pressure change of the muffler 3 is limited within the range of about 35 to 45 psi in the housing 10 as a whole, so that the pressure change is maintained in a state where there is no sudden or large change. 10) since the gas flows smoothly, it does not bring about flow resistance due to the formation of severe vortices and the like, and the accumulation of the medium P in the housing 10 is greatly reduced.

In addition, when analyzing the flow rate side of the gas in the housing 10 as shown in Figure 6, the gas having the initial velocity V is passed through the inlet pipe 12 at a relatively low velocity Va ( When introduced into the space in the third gap L3 of 10), the induction pipe 12 which is decelerated at Vc, which is a further lowered speed in the third gap L3, and then passes through the partition walls 11 and 11 '. After passing through '), the speed is slightly increased at the speed Vb, and then reduced to the speed Vc which is lowered as it is introduced into the space in the first interval L1.

At this time, it is a matter of course that the inside of the second interval L2 through which the guide pipe 12 'passes is lowered to Ve which is the lowest speed.

Subsequently, the gas in the first section L1 flows through the discharge pipe 13 and is lowered compared to Vc at the inlet portion thereof, and then gradually increases to Vd, which is higher than Vc, and communicates with the atmosphere 1. Is discharged through).

At this time, V is in the range of about 12 m / sec, Va is about 7 m / sec, Vb is about 4-5 m / sec, Vc is about 3-4 m / sec, Vd is about 6 m / sec and Ve is 1 m It has a distribution of / sec or less.

As described above, the silencer 3 discharges the gas of the third section L3 to the first section L1 more smoothly because the velocity of the gas passing through the induction pipe 12 'is greater than that of the third section L3. While the velocity distribution is gradually increased over the pipe 13, the gas flow in the housing 10 does not have a sudden speed change, which is included in the gas due to the gas flow characteristics in the housing 10. The shot coal P is continuously discharged from the housing 10 together with the gas, and the accumulation in the housing 10 is greatly reduced.

As described above, according to the present invention, the inlet pipe for introducing the exhaust gas in the housing of the silencer and the discharge pipe for discharging the gas and the induction pipes for inducing the gas flow in the housing are sequentially positioned upwardly at intervals and the partition wall The compartment space inside the housing, which is partitioned by means of an optimum ratio, is also formed in an optimum ratio, which induces a smooth flow while preventing sudden changes in the gas pressure in the housing, and accumulates in the housing under specific conditions such as rapid acceleration without using an expensive post-processor. There is an effect that can prevent the excessive discharge of the shot.

Claims (3)

Inlet pipe 12 provided downward with a predetermined distance (K) with respect to the center (O) of the housing (10) made of a closed end of a predetermined shape, and is substantially close to the center (O) of the housing (10) The discharge pipe 13 provided at a position and an induction pipe 12 'provided upward with a predetermined distance K' with respect to the center O of the housing 10, while inside the housing 10. The vehicle silencer is provided with a pair of first and second partitions (11, 11 ') for supporting the pipes (12, 12', 13) while dividing the entire space at a predetermined ratio. According to claim 1, wherein the inlet pipe 12 forms a bias interval (a) so as to be located relatively downward while being biased to one side on the cross-sectional center of the housing 10, the discharge pipe 13 is the housing 10 The center of gravity (c) is formed so as to be in close proximity to the center of the cross-section of the inlet pipe 12 so as to be biased, and the induction pipe 12 'is biased to one side on the center of the cross section of the housing 10 while being relatively biased. Vehicle silencer, characterized in that to form a bias interval (b) to be located above. According to claim 1, wherein the inner space partition ratio of the housing 10 is the first gap (L1) from the leading end portion in which the inlet pipe 12 is introduced to the first partition 11, and the first partition 11 A second gap L2 between the second partition walls 11 'provided at intervals and a third gap from the second partition walls 11' to an end portion of the housing 10 through which the discharge pipe 13 is discharged. Vehicle silencer, characterized in that (L3) forms about 35%, 20% and 45% of the total interval (L), respectively.