Advanced Variable Geometry Turbocharger for Diesel Engine Applications

Diesel engines face increasingly stringent emissions regulations worldwide. The trade-off between fuel economy and NOx emissions and between NOx and particulate emissions is becoming more critical. In light of these regulations and design trade-offs among many variables, engine-boosting systems have become increasingly important. An advanced variable nozzle turbocharger (AVNT™) is described. The innovative design is described along with key characteristics. The design features a minimization of additional parts associated with the variable geometry mechanism and electro-hydraulic actuation integrated with the bearing system. The impact of variable geometry turbocharging on diesel engine performance, fuel economy, torque, emissions and braking capability is described. It is shown that significant improvements in all five variables are readily possible with the use of this variable geometry turbocharger.