Design and Fabrication of Aqua Silencer For IC engines – Mechanical Project

Abstract –

An Aqua Silencer is a concept which is designed to replace conventional single unit engine silencers on board structure. It is made to deal with the control of overall emissions and undesirable sound at the engine exhaust of the vehicle. An aqua silencer is fitted to the exhaust pipe of the engine. The activated charcoal filters the harmful sulphur and nitrous content produced from the engine. Sound produced under water is less hearable than it produced in atmosphere.
Automobiles are not only the source of air pollution, other sources such as electric power generating stations, industrial and domestic fuel consumption, refuce burning, industrial processing etc. also contribute heavily to contamination of our environment so it is imperative that serious attempts should be made to conserve of our environment from degradation. An aqua silencer is an attempt in this direction; it is mainly dealing with emissions and sound produced in engine of automobile.

INTRODUCTION
An aqua silencer System is designed to replace conventional single unit engine silencers on board structures. With it‟s light weight and slender design, it offers a minimal ‘footprint’ while optimizing the entire exhaust system for low noise and reduced backpressure. It is used to control the noise and emission in IC engines. The reason why we go for aqua silencer is, in today life the air pollution causes physical ill effects to the human beings and also the environment. The main contribution of the air pollution is Automobile releasing the gases like carbondioxide and unburnt Hydrocarbon.
In order to avoid this type of gases by introducing this aqua silencer. It is fitted to the exhaust pipe of the engine, Sound produced under water is less hearable than it produced in atmosphere. This mainly because of small sprockets in water molecules, which lowers its amplitude thus, lowers the sound level. The emission can be controlled by using the activated charcoal layer and it is highly porous and posse extra free valences so it has high absorption capacity. So absorb the gases from the engine and release much less position to the environment. The noise and smoke level is considerable less than the conventional silencer, no need of catalytic converter and easy to install.
In this silencer, the Charcoal and Water so it is called hybrid aqua silencer, and it is useful in automobile, industry, DG sets & DG machines, Marin and Boats also so, It is known as hybrid universal aqua silencer.

COMPONENTS AND EXPLANATION

Perforated Tube :

The perforated tube consists of number of holes of different diameters. It is used to convert high mass bubbles to low mass bubbles. The charcoal layer is pasted over the perforated tube.

Charcoal Layer:

The charcoal layer has more absorbing capacity because it has more surface area. This charcoal is called as ACTIVATED CHARCOAL. It is produced by heating the charcoal above 1500 „c for several hours in a burner. Its surface area gets increased.

Outer Shell :

The whole setup was kept inside the outer shell. It is made up of iron or steel. The water inlet, outlet and exhaust tube was provided in the shell itself.

U-Bend :

The U Bend is provided instead of a non-return valve which is a mechanical device , which normally allows fluid (liquid or gas) to flow through it in only one direction. The Aqua silencer was filled with water and it is directly connected to the exhaust pipe of the engine. There is a chance for the water to get enter into the engine cylinder. To avoid this, U bend is used.

Flange :

A flange joint is a connection of pipes, where the connecting pieces have flanges by which the parts are bolted together. Here flange is used to connect the silencer to the engine.

CONSTRUCTION
Basically an aqua silencer consists of a perforated tube which is installed at the end of the exhaust pipe. The perforated tube may have holes of different diameters. The very purpose of providing different diameter hole is to break up gas mass to form smaller gas bubbles the perforated tube of different diameters. Generally 4 sets of holes are drilled on the perforated tube. The other end of the perforated tube is closed by plug. Perforated tube contains lime water inside it which chemically reacts with exhaust gas from the engine. Around the circumference of the perforated tube a layer of activated charcoal is provided and further a metallic mesh covers it. The whole unit is then
placed in a water container. A small opening is provided at the Top of the container to remove the exhaust gases. A U bend is provided at the end of perforated tube which functions as a non-return valve which prevents the back flow of exhaust gas and lime water back to the engine.

Working Layout
As the exhaust gases enter in to the aqua silencer, the perforated tube converts high mass bubbles in to low mass bubbles after that they come in to contact with lime water they chemically react with it and pass through the pass through charcoal layer which again purify the gases. It is highly porous and posse extra free valences so it has high absorption capacity. Since the charcoal layer is covered with outer shell which is filled with water. Sound produced under water is less hearable than it produced in atmosphere. This is mainly because of small sprockets in water molecules, which lowers its amplitude thus, lowers the sound level hence aqua silencer reduces noise and pollution.

CONCLUSION
The aqua silencer is more effective in the reduction of emission gases from the engine exhaust using perforated tube, lime water and charcoal by using perforated tube the back pressure will remain constant and the sound level is reduced. By using perforated tube the fuel consumption remains same as conventional system by using water as a medium the sound can be lowered and also by using activated charcoal in water we can control the exhaust emission to a greater level. The water contamination is found to be negligible in aqua silencer. It is smokeless and pollution free emission equivalent to the conventional to the silencer.