23-09-2014, 04:45 PM
TURBOCHARGER is a device which sends more air in the engine for the proper burning of fuel. Thus increases the working efficiency of our engine. PROBLEM WITH PRESENT TURBOCHARGER is that it works on the pressure and kinetic energy of exhaust gases made by engine working. But during low speed of engine, it cannot produce enough exhaust to propel turbocharger. MODIFICATION DONE IN PRESENT TURBOCHARGER is that it will work on the energy given to it by crankshaft with help of belt in place of exhaust gases. Or with the help of battery motor during slow running of engine then with help of exhaust gases during fast running of engine. An automatic electrical switch is also needed to control battery motor with reading changing speed of engine.
PROJECT REPORT
ENGINE
It is a device which converts the heat energy produced by burning of fuel in combustion chamber into the mechanical energy. It is also known as compression-ignition engine. It uses the heat of compression for ignition fuel which is injected in compression chamber.
Diesel engine has highest thermal efficiency of any internal or external combustion engine due to its high compression ratio.
Tata is using CUMMINS Company
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engines in their vehicles. It has many accessories for its better performance. It has many cooling devices for cooling engine. Many other systems are being attached to send more air in the combustion chamber for engine`s better performance. A turbo type device is also being used in vehicle to send more air.
TURBOCHARGE SYSTEM
It is device which has two fans in it connected with the same shaft. But both these fans are separated by a partition so that air from one side cannot go to other side. Fan on one side is driven by the exhaust gases coming out from the engine.
So when this fan rotates, it rotates other fan present on other side of partition, because of same shaft. So when the second fan rotates, it sucks air from outside send it to combustion chamber of engine. As we send more amount of air in engine as well as more mass of OXYGEN is send to engine for the better combustion of our fuel. In this way our fuel gets completely burnt. So by doing this we can send more air in the engine to increase engine`s efficiency.
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So when we are using turbocharger in our vehicles, it sends more amount of compressed air which is containing large mass of OXYGEN molecules in it. So because of higher mass of oxygen, fuel in combustion chamber burn completely and increases the working capacity of our engine. In this way we can increase the power of our engine without any cost or any type of extra effort.
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We can say that this type of turbo charger system is the cheapest method to increases power of our engine. This is cheaper method because it never uses engine or any other electrical energy which affect our engine performance. It uses only pressure and kinetic energy of exhaust gases to drive its fans. It also compresses the air in a limited amount. So prevent the heating up of compressed air which reduces the efficiency of burning fuel by expanding itself reducing mass of air OXYGEN in it.
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PROBLEM WITH PRESENT TURBO SYSTEM
As we know that our present turbocharger system is running with the help of exhausts gases. When our engine is at low speed, it is not able to produce exhaust gases at sufficient kinetic and pressurized energy which can drive our turbocharger fan.
After getting a sufficient running speed, our engine is able to produce so much exhaust that it can run turbo`s fan. At low speed, turbocharger fan cannot work. During starting of engine, it is not able to produce any power. Our engine has to work only on air that it can suck during its suction stroke, which has not sufficient amount of oxygen mass in it.
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So in any jam condition or on off roads or at hilly areas where we have to drive our vehicle at low speed and our engine need more power to drive vehicle, but at the same time, due to low speed our turbo system is not working properly. So our engine is not able to propel vehicle at such low efficiency and need more quantity of fuel. So in this way, working efficiency of our engine decreases a lot. So we have made some modification in this turbocharger system.
MODIFICATION IN TURBOCHARGE SYSTEM
As our older turbocharger system is insufficient during the slow running of our engine, so we tried to make some modification in the present system to increases turbo system efficiency.
We are trying to connect the turbocharger fan`s shaft to engine pulley with the help of belt, chain or gears. So when we connect the charger with belt then it will also work during the slow running of engine. So we can say that it is much more good method of charging.
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It is good method because during slow running of engine, charger also moved with slow speed and during fast running of engine, charger also moves at high speed and send air in engine as it needs high or low. We also fitted some safety valves in the way of air from charger to combustion chamber.
Mainly it is very useful during the starting of engine and also during when vehicle is off road or in any jam. In this we can also adjust its timing of producing pressurized air with the opening and closing of combustion chamber valves. So we say that it is better method of charging then exhaust type turbo charger.
Safety valves are also needed with this type of charger because during running, this type of charger can produce excess
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pressure in the way which would result in heating up of air. By heating up of air, it will expand before going to engine and mass of oxygen get decreased in it. So working efficiency of engine decreases.
We have to keep another point in our mind. That is this, as we attach more accessories to our engine`s crankshaft, they will consume more engines power. So the power gone to our vehicles wheel decreases.
This type of chargers can work only with big engines. If these type of charger are also get connected with small engines, they decreases engines power by consuming engine`s power itself for working with help of belt-pulley system.
Then we also tried a new type of turbo charger which is also suitable for small engines. It is driven with the help of electric motor and current given to it by battery and also with the help of exhaust gases. Mainly it is a twin type turbo charger.
TWIN TURBO CHARGER
This type of charger uses both electric and exhaust gases power for working. 66
In this system, we join the shaft of our turbo charger fan with other fan shaft which is run by exhaust gases. Then this shaft is connected to battery motor shaft which is run by battery current. In this system we need an electric switch. A sensor which can sense R.P.M. of engine is also needed.
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When we start our engine, our sensor will sense R.P.M. of engine with the help of electric current and then send signal to the electric switch. Electric switch is made to work with in a limited range of R.P.M.
If the R.P.M. are up to the point that the exhaust produced by engine is sufficient to move the turbo charger, then sensor send signal to electric switch. Then electric switch cut off the power supply to electric motor and our turbo will work on exhaust gases only.
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If the R.P.M. of engine are so low that the exhaust produced is not enough to move the move the turbo system, then sensor will sense the speed and send signal to the electric switch. The electric switch will read low R.P.M. and start sending electric current to motor. Motor will start working, thus turbo will start.
In this way our turbo will work at high speed as well as low speed of engine and our engine will work with full efficiency.
MODIFICATION IN WORKSHOP LAYOUT
There are some problems in layout of workshop layout. During the service of any vehicle in the plant a lot of time is consume in placing spare parts which are removed during service and also in picking up tools for repair work. So plant goes in a heavy labor loss.
When any spare part is removed from vehicle, workers place them around vehicle like tires. These create a lot of problem when workers move around vehicles for service.
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So we recommended them to make special racks where they can place removed parts like tiers, nuts etc. by this the fear of losing spares also reduces. By placing thing at their right place, we also reduced their harassment which they produce during wondering of workers around vehicles. In this way the time consumed during service of vehicle reduces. So profit of company increases.
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We also suggest them to use trolleys for the tools of workers. By using these, they will collectively go to vehicle with their tools in place of wondering for the tools here and there again and again.
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So these are our projects during my training in the PASCO motors [CHD.]
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