Variable Turbine Area (VTA)

Lower emissions and better fuel economy

Radial turbochargers featuring adjustable nozzle vanes ahead of the turbine to vary charge air output are in wide use on automotive diesel engines.

MAN Energy Solutions has taken up the challenge of transferring this technology to large turbochargers with both axial and radial turbines for installation on large diesel engines burning heavy fuel oil (HFO), probably the most difficult engine fuel in daily use.

MAN Energy Solutions’ solution is the VTA (variable turbine area) technology which is now offered as an option for radial TCR and axial TCA turbochargers.

How VTA works

The VTA system consists of a nozzle ring equipped with adjustable vanes which can replace the fixed-vane nozzle rings in MAN Energy Solutions’ standard TCA and TCR turbochargers.

By altering the pitch of the adjustable vanes, the exhaust gas pressure is regulated and thus the air amount can be precisely matched to the quantity of injected fuel at all points in an engine’s load and speed range. The result is reduced specific fuel consumption, reduced emissions of HC and CO2 and improved engine response.