1
Adjustable turbine nozzle ring (VTA)
1.1
Range of applications
The VTA was designed for applications on turbocharged large diesel engines
with different load profiles. Due to its adjustability, the VTA adapts the turbo-
charging characteristics so that the engine works efficiently over a wide load
range.
In order to meet the requirements of modern large diesel engines, a variable
fresh air supply is required. One particularly efficient way of achieving this is
to use an adjustable turbine nozzle ring, or VTA. This modifies the pressure
level in the engine by adapting the narrowest nozzle ring cross section for the
air flow. The area through which the air flows is modified by adjusting the
guide vanes of the turbine nozzle ring.
If adjusting the guide vanes makes the air flow cross section narrower, this
increases the speed of the air flow to the turbine wheel. This increases the
turbocharger speed, thereby causing the charge pressure on the compres-
sor side to rise.
The VTA technology is available for all turbocharger sizes in the TCA Series
and can be used with both 2-stroke and 4-stroke engines. Both diesel
engine and gas-powered engine applications can be improved significantly
using a VTA.
Engine performance is optimised in accordance with customer requirements
by means of adapted control programs.
See table
Overview – VTA range of applications
.
Figure 1: TCA turbocharger with adjustable turbine nozzle ring
Functional Principle
VTA for TCA Turbocharger
2013-12-04 - de
1 Adjustable turbine nozzle ring (VTA)
1.1 Range of applications
MAN Diesel & Turbo
1
EN-US
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