Exhaust gas turbocharger for commercial vehicles

Future requirements will demand that exhaust gas turbochargers combine the following:

  • Reduction in fuel consumption and therefore CO2 savings 
  • Compliance with emission standards
  • Good responsiveness (low-end torque)
  • Outstanding durability
  • Optimal performance indicators

BMTS Technology supplies the right product portfolio to meet all these demands, with every turbocharger (T/C) tuned optimally and specifically to the engine.

A family of TC´s for commercial vehicle engines with power outputs from 30 to 560 kW has been developed. Because of the stringent demands regarding service life, wastegate boost pressure regulation is used for the commercial vehicles segment.

Turbocharging

Schematic diagram of two-stage turbocharging – commercial vehicle large-scale applications variant: with intercooling – classic R2S only with HP EGR
Schematic diagram of two-stage turbocharging – commercial vehicle large-scale applications variant: with intercooling – classic R2S only with HP EGR

Turbocharging allows a greater air mass to enter the combustion chamber, and more fuel to be utilized. This leads to a greater power output. In comparison with the naturally aspirated engine, turbocharging produces a higher performance yield, while maintaining the same displacement, and increases the engine’s low-end torque.

Conversely, for a specific engine output, the displacement can be reduced, or "downsized." Downsizing reduces fuel consumption and consequently CO² emissions. The reason for the fuel saving is that the engine is operating with a higher brake mean effective pressure (BMEP) in engine map areas with higher specific loads and thus with greater fuel efficiency.

Design of the exhaust gas turbocharger

The exhaust gas turbocharger (T/C) uses the energy from the exhaust gas to charge the combustion engine. In contrast to mechanical supercharging, the T/C does not require any mechanical driving power. This directly leads to reductions in fuel consumption. The T/C comprises of two flow mechanisms: an exhaust gas turbine, which extracts the energy from the exhaust gas, and a compressor that compresses the intake air. The exhaust gas turbocharger consists of several assemblies:

  • Exhaust gas turbine with turbine wheel and turbine housing
  • Compressor with impeller and compressor casing
  • Core unit with rotor and bearing
  • Regulating device for boost pressure (variable turbine geometry (VTG) or wastegate)