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How Do Exhaust Gas Turbochargers for Passenger Cars Work?


Cars run at a high level when you use a turbocharger on them. An exhaust turbocharger is used to compress the air that gets carried into the vehicle’s engine. In comparison to naturally aspirated engines, the firing of the cylinders is much more intense. At the same time, the engine’s performance is increase while reducing the consumption of fuel and improving the emissions values.


Design of Exhaust Gas Turbo Chargers

Exhaust gas turbochargers use the power from you vehicle’s exhaust gas to charge the combustion engine. When fitted to a direct injection diesel engine, it greatly reduces the fuel consumption of the engine.Contrary to the use of mechanical superchargers, these turbochargers do not entail wasting any sort of mechanical power. This leads to lower fuel use.Exhaust gas turbochargers have several assemblies which are as follow:

      ·         Exhaust gas turbines with turbine and wheel housing

      ·         A core unit that includes a bearing and rotor

      ·         Compressor with implier and compressed casing

      ·         Regulation deviceto control the boost pressure


Function

During exhaust gas turbo charging, exhaust gas power is used to drive the turbine, which otherwise would just be releasedinto the environment. The compressor is mounted on the shaft of the turbo charger opposite to the turbine. The compressor draws the combustion of air and directs it to the engine in compressed form. This is most pronounced in quality turbocharges like the Holset HX35 turbo.


The main parts of the exhaust turbocharger are the turbine and compressor, between which there is a mechanical connection which is established via a common shaft. The turbine is driven by exhaust gases from the engine and supplies the drive energy for the compressor. In the majority of the cases,centrifugal compressors and centripetal turbines are utilized for the turbochargers.


Charging Pressure Regulation

In order for the turbo engine to reachits optimum performance level, the charging pressure of the exhaust turbocharger must be matched to the engine load and the engine speed. Bypassing the turbine side is the best method to charge the pressure regulator. The turbine is small enough to meet the needs of the torque responses at low speed and ensure that the engine drives well. Shortly before the maximum torque is reached, more exhaust gases are supplied to the turbine in order to generate more pressure.


Once the required charging pressure is reached, exhaust gases are directed around the turbine through a bypass. The changing pressure control valve opens and closes and the bypass are controlled by a spring loaded membrane on the basis of charging pressure. In modern diesel engines,the variable turbine geometry has been carefully designed like a work of art.


Need for Passenger Cars

Future requirement of exhaust gas turbochargers includes the following:

      ·         Decrease of fuel consumption and thereby saving the CO2

      ·         Low end torque for a more enjoyable driving experience

      ·         Compliance with the established emission standards

      ·         Outstanding durability and long-lasting quality

      ·         Optimal performance indicators

 

Constantly adapting the turbine cross section by changing the driving conditions of the engine also reduces the fuel consumption and emission. The engine torque, which already has given low speeds with carefully adopted control strategy enables a perceptible improvement in driving dynamics which are being achieved.