How does a turbocharger work on a diesel

Cars with turbochargers often need to run on higher octane fuel to avoid knock. If the boost pressure is really high, the compression ratio of the engine may have to be reduced to avoid knocking. One of the main problems with turbochargers is that they do not provide an immediate power boost when you step on the gas.

It takes a second for the turbine to get up to speed before boost is produced. This results in a feeling of lag when you step on the gas, and then the car lunges ahead when the turbo gets moving. One way to decrease turbo lag is to reduce the inertia of the rotating parts, mainly by reducing their weight. This allows the turbine and compressor to accelerate quickly, and start providing boost earlier. One sure way to reduce the inertia of the turbine and compressor is to make the turbocharger smaller.

A small turbocharger will provide boost more quickly and at lower engine speeds, but may not be able to provide much boost at higher engine speeds when a really large volume of air is going into the engine. It is also in danger of spinning too quickly at higher engine speeds, when lots of exhaust is passing through the turbine.

Most automotive turbochargers have a wastegate , which allows the use of a smaller turbocharger to reduce lag while preventing it from spinning too quickly at high engine speeds. The wastegate is a valve that allows the exhaust to bypass the turbine blades.

The wastegate senses the boost pressure. If the pressure gets too high, it could be an indicator that the turbine is spinning too quickly, so the wastegate bypasses some of the exhaust around the turbine blades, allowing the blades to slow down. Some turbochargers use ball bearings instead of fluid bearings to support the turbine shaft. But these are not your regular ball bearings -- they are super-precise bearings made of advanced materials to handle the speeds and temperatures of the turbocharger.

They allow the turbine shaft to spin with less friction than the fluid bearings used in most turbochargers. They also allow a slightly smaller, lighter shaft to be used.

This helps the turbocharger accelerate more quickly, further reducing turbo lag. Ceramic turbine blades are lighter than the steel blades used in most turbochargers. Again, this allows the turbine to spin up to speed faster, which reduces turbo lag. Some engines use two turbochargers of different sizes. The smaller one spins up to speed very quickly, reducing lag, while the bigger one takes over at higher engine speeds to provide more boost.

When air is compressed, it heats up; and when air heats up, it expands. So some of the pressure increase from a turbocharger is the result of heating the air before it goes into the engine. In order to increase the power of the engine, the goal is to get more air molecules into the cylinder, not necessarily more air pressure. An intercooler or charge air cooler is an additional component that looks something like a radiator , except air passes through the inside as well as the outside of the intercooler.

The intake air passes through sealed passageways inside the cooler, while cooler air from outside is blown across fins by the engine cooling fan. In order to meet our requirements for power, this requires air; putting in more air presents far more problems than putting in more fuel. Air is around us all the time and is under pressure, at sea level this pressure is about 15 p.

It is this pressure that forces air into the cylinders. To increase the air flow, an air pump turbocharger is fitted and compressed air is blown into the engine.

This air mixes with the injected fuel allowing the fuel to burn more efficiently so increasing the power output of the engine. One other side of turbocharging, which may be of interest, is an engine which works regularly at high altitudes, where the air is less dense and where turbocharging will restore most of the lost power caused by the drop in air pressure.

The waste exhaust gases of the engine are utilised to drive a turbine wheel, which is connected to a compressor wheel by a shaft. The compressor or air wheel sucks in air through the air filters and passes this into the engine. As the waste gases are expelled from the engine, they are directed to the turbine or hot wheel of the turbo and so completes the cycle. Our cost-effective turbocharger repair services include complete factory replacements, cartridge replacements, and housing repairs and replacements.

When the repair is done to factory specifications, our standard month warranty features unlimited miles or hours as long as the unit is operated and maintained to factory specifications by the owner. We do not charge for estimates. Turbo-diesel: Diesel Engine Turbocharger Assembly. Discover Garrett Original Reman Ball Bearing Go Mainstream Garrett Electric Boosting The Garrett Electric Compressor Differentiated Garrett Technologies for Gasoline Applications Garrett Cybersecurity Advanced Thrust Bearing Design Medium Duty and Ball Bearing Advanced Wastegate for Gasoline Choose your path Follow the journey of your preference, for more relevant information.

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