RU2255229C2 - Internal combustion engine exhaust nuffler - Google Patents

Abstract

FIELD: mechanical engineering; internal combustion engines.

SUBSTANCE: proposed muffler contains intake manifold, receiver, exhaust pipeline, muffler housing divided by partitions into two or more spaces, exhaust branch pipe. Receiver is connected with muffler housing by additional pipelines of larger length providing entering in time of compression waves into muffler housing between waves getting into muffler housing from first pipeline. Each pipeline is in communication through outlet end face with one or different spaces, and exhaust pipelines of larger length are made with larger passage section providing cyclic gas flow rate equal to that of flow rate in shorter pipeline. Exhaust pipelines of different length can be arranged in one housing (all pipelines or part of them).

EFFECT: improved efficiency of noise damping.

2 cl, 1 dwg

Description

The invention relates to the field of engine engineering and can be used to reduce exhaust noise.

A device for suppressing the noise of an exhaust from an internal combustion engine is known, comprising a housing divided by a partition into a main and damping cavity, an exhaust pipe and an intermediate pipe located in the housing, made in one with the inlet pipe and having a window in the initial portion communicating with the main cavity, this intermediate pipe is made in the form of a spiral, placed on the periphery of the housing and communicated with the output end with a damping cavity, and the exhaust pipe is placed in the main cavity (RF Patent No. 2013575, CI ⁵ F 01 N 1/08, 30.05.94).

The disadvantage of the analogue is the high hydraulic resistance of the spiral pipe and the limited efficiency of damping noise.

A device is known, selected as a prototype, containing an exhaust manifold, receiver, exhaust pipe, silencer body, divided by partitions into cavities, exhaust pipe (AS USSR No. 643659, class F 01 N 7/02, published in 1979) .

A disadvantage of the known device is the lack of noise reduction efficiency.

The objective of the invention is to increase the efficiency of damping noise by introducing a second pipeline of greater length.

This object is achieved by the fact that in the device for damping the exhaust noise of an internal combustion engine containing an exhaust manifold, receiver, exhaust pipe, silencer body divided by partitions into two or more cavities, the exhaust pipe, in contrast to the prototype, the receiver is connected to the silencer body by additional pipelines of greater length, ensuring the arrival in time of compression waves into the silencer body between the waves emerging into the silencer body from the first pipeline, with each pipe connecting it has an outlet end face with one or different cavities, the outlet pipelines of greater length are made with a large bore, compensating for the increase in friction with an increase in the length of the pipeline. In this case, part or all of the exhaust pipes of different lengths can be made in one housing.

The invention is illustrated by the drawing which shows a diagram of a device for damping the exhaust noise of an internal combustion engine.

A device for suppressing the noise of an exhaust from an internal combustion engine comprises an exhaust manifold 1, a receiver 2, an exhaust pipe 3, a silencer body 4 divided by partitions into two or more cavities, an exhaust pipe 5, while the receiver 2 is connected to the silencer housing 4 by a second exhaust pipe 6 larger lengths than the first. The exhaust pipe 3 and the exhaust pipe 6 are connected by output ends with one or different cavities. In addition, the receiver 2 can be connected to the silencer housing 4 with three or more pipelines of different lengths.

A device for damping the exhaust noise of an internal combustion engine operates as follows. Compression waves from the receiver 2 to the silencer body 4 move along the exhaust pipes 3 and 6 (of different lengths) with approximately the same speed. Therefore, the release of a portion of gas into the silencer housing 4 from the exhaust pipe 6 occurs later. The lengths of the exhaust pipes 3 and 6 are selected in such a way as to ensure the arrival of compression waves to the silencer body 4 at regular intervals and, accordingly, a more uniform flow of gas into the silencer body 4.

The connection of the receiver 2 with the silencer body 4 with a second pipe 6 of a larger length allows to reduce fluctuations in the flow rate of exhaust gases.

The implementation of the exhaust pipes 6 of greater length with a large bore allows you to compensate for the increase in hydraulic resistance. If the exhaust pipes 3 and 6 are made of the same cross section, then the cyclic gas flow rate through the long exhaust pipe will be less than through the short one due to the greater hydraulic resistance. With an increase in the cross section of the exhaust pipe, its hydraulic resistance decreases. Therefore, the implementation of a longer exhaust pipe with a large cross-section provides the same cyclic gas flow from both exhaust pipes and, accordingly, a more uniform flow of gas into the muffler. The diameters of the long and short pipelines can be determined by numerical calculation of the transient gas flow through the exhaust system. For example, with a pipe length ratio of two, the pipe diameter ratio should be 1.15. The diameter of the longer pipeline can be determined by an approximate relationship

where d _k is the diameter of the short pipeline; l _d , l _to - the lengths of the long and short pipelines, respectively.

The connection of the receiver 2 with the silencer housing 4 with three or more exhaust pipes 3, 6 of different lengths can further reduce the fluctuation of the exhaust gas flow. If there are two exhaust pipelines 3 and 6 connecting the receiver 2 to the silencer body 4, the cyclic portion of the exhaust gas is divided into two parts. If the receiver 2 is connected to the silencer housing 4 with three or more pipelines of different lengths, then the cyclic portion of the exhaust gases is divided into three or more parts, which ensures a more uniform gas flow into the silencer housing 4.

The implementation of part or all of the exhaust pipelines 3, 6 of different lengths in one housing, for example, coaxial placement of pipelines, can reduce the dimensions of the exhaust system and facilitate its layout on the power plant.

So, the claimed invention improves the efficiency of damping the noise of the release.

Claims (2)

1. A device for damping the noise of an exhaust from an internal combustion engine, comprising an exhaust manifold, a receiver, an exhaust pipe, a silencer body, divided by partitions into two or more cavities, an exhaust pipe, characterized in that the receiver is connected to the silencer body with additional longer pipelines, providing arrival in time of compression waves to the silencer body between the waves emerging into the silencer body from the first pipe, each pipe is communicated by the output end with one or different cavities moreover, the exhaust pipelines of greater length are made with a large bore, providing a cyclical gas flow rate of the same as through a short pipeline. 2. The device according to claim 1, characterized in that the pipelines of different lengths are made in one housing.