08-16-2017, 09:16 PM
TURBO CHARGING BY VARIABLE VANE GEOMETRY
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INTRODUCTION TO TURBOCHARGING
A turbocharger, or turbo, is a centrifugal compressor powered by a turbine which is driven by an engine's exhaust gases. Its benefit lies with the compressor increasing the pressure of air entering the engine thus resulting in greater performance (for either, or both, power & efficiency). They are popularly used with internal combustion engines (e.g. four-stroke engines like Otto cycles and Diesel cycles).
ADVANTAGES OF EXHAUST GAS TURBOCHARGING
The high altitude performance of a turbocharged engine is significantly better
The power to weight ratio of the exhaust gas turbocharged engine is much better than that of the naturally aspirated engine
Compared with a naturally aspirated engine of identical power out put , the fuel consumption of a turbo engine is lower , as some of the normally wasted exhaust energy contributes to the engine efficiency . Due to the lower volumetric displacement of the turbo engine , frictional and thermal losses are less.
WORKING OF VARIABLE GEOMETRY SYSTEM
At low rpm
The vanes are partially closed, reducing the area hence accelerating the exhaust gas towards the turbine. Moreover, the exhaust flow hits the turbine blades at right angle.Both makes the turbine spins faster