RU2503828C2 - Acoustic electric noise silencer - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: acoustic electric noise silencer includes a housing, inside which an expansion chamber is formed. Inlet and outlet branch pipes are mounted on the chamber ends. The chamber is separated with a transverse partition wall into high-frequency and low-frequency noise reduction zones. A perforated pipe is mounted inside it and connects inlet and outlet branch pipes; noise silences housing is made from ferromagnetic material. Noise silencer housing is placed into a cylinder; with that, the cylinder is attached to a transport vehicle body, and noise silencer inside the cylinder is fixed by means of springs working for tension. A multiturn coil is applied onto (built into) a cylinder and its outputs are connected through a rectifying device (rectifying bridge) and a relay governor to a transport vehicle accumulator.

EFFECT: reduction of acoustic noise level and reduction of ICE energy losses caused by using known noise silencers.

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Description

The invention relates to devices that reduce noise arising from a running engine, can be used in ramjet exhaust systems of vehicles equipped with internal combustion engines (ICE).

Exhaust silencers for internal combustion engines are known, the structures of which are described in RF patents Nos. 641140, 1245726, 1043329, 1019082. These exhaust silencers for internal combustion engines contain a cylindrical body with end walls, inlet and outlet chambers, inlet and outlet pipes, sections of which are respectively located inside the cavities of the inlet and outlet chambers. Such silencers are relatively simple to manufacture, but not sufficiently effective in noise suppression to meet modern requirements of more stringent standards for the external and internal noise of vehicles, in addition, 3-5% of the internal combustion engine power is spent on noise suppression.

As a prototype adopted a silencer according to the patent of Russian Federation №2333370 "Noise suppressor", class F01N 00, decl. 12/06/2006. A silencer containing an expansion chamber, at the ends of which an inlet and outlet pipe is mounted, and a resonator made in the form of a sleeve mounted on the end of the chamber and communicated with its cavity, characterized in that it is equipped with a perforated pipe installed in the expansion chamber, connecting to each other the inlet and outlet pipes, while the edges of the holes on the inner surface of the perforated pipe are rounded, and the expansion chamber is divided into two zones: a zone of high-frequency noise reduction, located with on the side of the inlet pipe, in which the material that reduces noise, and the zone of low-frequency noise reduction located on the side of the outlet pipe are placed.

The disadvantage of this muffler is that there is a perforated pipe in the expansion chamber, which creates additional noise, as well as resistance to the flow of exhaust gases.

The technical result of the invention is to reduce the level of acoustic noise and reduce energy losses of internal combustion engines caused by the use of known noise suppressors.

The technical result is achieved by the fact that in an acoustoelectric silencer containing a housing inside which an expansion chamber is formed, at the ends of which an inlet and outlet pipe is mounted, divided by a transverse partition into zones of high-frequency and low-frequency noise reduction, a perforated pipe is connected inside that connects the input and output pipes characterized in that the silencer body made of ferromagnetic material is placed in the cylinder, while the cylinder is rigidly attached to the trans body tailor means, and the muffler inside the cylinder is mounted using tensile springs, a multi-turn coil is applied (built in) to the cylinder, the outputs of which are connected through the rectifier device (rectifier bridge) and the relay-regulator to the vehicle battery.

The claimed device is illustrated by drawings, which show:

figure 1 is an embodiment of the inventive muffler;

figure 2 is a drawing illustrating the source of acoustic noise.

The design of an acoustoelectric silencer for exhaust gases of internal combustion engines shown in Fig. 1 contains an exhaust pipe 1, a damper element 2, an intake pipe 3, which can be divided into an external section 3a and an internal section 3b, spring elements 4 that are fixed to the silencer body 5 between the silencer body and the cylinder, the guiding element 6. Inside the acoustoelectric silencer may contain (be absent) any combination of reflecting, absorbing, redistributing electric cops 7. At the outlet of the muffler exhaust pipe 9, consisting of the inner 9a and outer 9b portion. The cylinder is rigidly fixed to the vehicle body 13. A multi-turn coil 8 is wound on top of the cylinder, connected to a rectifier bridge 10, the outputs of which are connected through the relay regulator 11 (from the vehicle) to the battery of the vehicle 12.

The acoustoelectric silencer operates as follows.

Any silencer made of ferromagnetic materials is placed in a cylinder. In this case, the cylinder is rigidly fixed to the vehicle body, and the silencer body is fixed by means of tensile spring elements to the cylinder. The external part of the inlet pipe of the silencer is attached to the pipeline of the exhaust system by means of a damping element made in the form of a corrugated pipe of high-temperature material, in order to prevent damage to the pipeline during transverse vibrations of the muffler. A multi-turn coil is wound (fixed) on the cylinder, resulting in a solenoid.

The solenoid is a cylindrical wire coil (Bondarev B.V. General Physics Course. Book 2: Textbook - Moscow: Higher School, 2003, p. 148).

The solenoid is characterized by the number of turns N wound per unit length l. Each pair of turns located symmetrically with respect to a certain plane perpendicular to the axis of the solenoid creates magnetic induction B parallel to the axis at any point on this plane. Consequently, the resulting field at any point inside and outside the infinite solenoid can only have a direction parallel to the axis. (Saveliev I.V. Course in General Physics, Volume 2. - M .: Nauka, 1978, p.142).

F _l = qVB = qBµ ₀ NI / l, where

F _L - Lorentz force;

q is the charge;

V is the charge rate;

B - magnetic induction.

Outside the solenoid, the field is absent. It follows from the circulation theorem and the Gauss theorem that inside the solenoid B = const. To find the value of B, it is necessary to apply the circulation theorem to a rectangular contour, one side of which passes along the generator inside the cylinder, and the other outside. Magnetic induction inside the solenoid is equal to (Chernutsan A.I. A Short Course in Physics. - M.: FIZMATLIT, 2002, pp. 107-109):

B = µ ₀ NI / l, where

B - magnetic induction;

µ ₀ is the magnetic constant;

N is the number of turns;

I is the current strength;

l is the length of the solenoid.

According to Maxwell's theory, the variable electric and magnetic fields are interconnected and simultaneously exist in space. Where there is one of these fields, there is certainly another field. During oscillations of a silencer made of ferromagnetic material inside a multi-turn coil, an alternating magnetic field and a corresponding alternating voltage occur at the terminals of the coil. Current flows through the coil, a magnetic field appears inside the cylinder, which prevents the muffler from oscillating up and down.

Exhaust gases, together with the noise energy of the gas stream, during the implementation of the working process of the internal combustion engine (ICE), are led to the muffler through the pipeline of the exhaust system, distributed through the inlet pipe and enter the cavity of the inlet chamber of the muffler. In this case, the gases create acoustic pressure due to a collision with the walls of the silencer (V ₁ ), due to which its transverse vibrations occur, which are the source of acoustic noise. The second source of noise is the pressure difference between the gases at the outlet of the muffler and atmospheric pressure (V _a ) (figure 2).

V = V ₁ + V _a

In the framework of the proposed device, the acoustic pressure V _a is considered unchanged, and all actions are aimed at reducing the acoustic pressure V ₁ .

When moving or deforming the circuit with the current in a constant magnetic field, the Ampere forces directed in each section perpendicular to the current do the mechanical work δA _⊥ = IdФ.

Under the influence of a magnetic field, such oscillations decrease, but are absent in the limit, therefore, the noise level decreases. At the same time, electric energy is generated that enters the vehicle’s battery through a rectifier device and a relay-regulator.

Since the full work of the Lorentz force on any moving particle is equal to zero, the same magnitude but opposite sign is performed by a magnetic field (the tangential component Lorentz force) on free charges moving along the contour, which leads to the appearance of an additional induction emf in the circuit.

δA _|| = IdF = Bdq

, где

where

E is the electromotive force (EMF) of induction;

I is the current strength;

A _|| - mechanical work of the Ampere force;

F - magnetic flux;

t is the unit of time;

q is the charge.

The technical and economic effect consists in the fact that by using the laws of acoustic and electromagnetic fields, the vibration amplitude of the muffler and its elements is reduced, and, consequently, the level of acoustic noise is also reduced, the degree of mechanical wear of the muffler is also reduced (less than the amplitude of alternating mechanical effects), ICE irretrievable power loss level (by-product of acoustic noise) due to acoustoelectric conversion of acoustic pressure at the silencer section into ektricheskuyu energy returned to the grid engine.

Claims (1)

An acoustoelectric silencer comprising a housing inside which an expansion chamber is formed, at the ends of which an inlet and outlet pipe is mounted, divided by a transverse partition into zones of high-frequency and low-frequency noise reduction, a perforated pipe is mounted inside that connects the inlet and outlet pipes, characterized in that the silencer body made of ferromagnetic material is placed in the cylinder, while the cylinder is rigidly attached to the vehicle body, and the muffler inside the cylinder and is attached via the springs working on tension is applied to the cylinder (inserted) multiturn coil, which exits through the rectifier device (bridge rectifier) and the relay controller connected to the vehicle battery.

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