Variable geometry turbocharger having internal bypass exhaust gas flow

摘要

Variable geometry turbochargers include a turbine housing having an exhaust gas inlet and outlet, a volute connected to the inlet, and typically a nozzle wall adjacent the volute. The turbine housing includes a bypass exhaust gas flow port disposed internally therein having an inlet opening positioned upstream from the turbine wheel, and a outlet opening positioned downstream from the turbine wheel. The inlet opening is exposed for facilitating bypass exhaust gas flow through the turbocharger when a respective vane is actuated or moved into an open position. The turbine housing may also include a specially configured nozzle wall terminal edge designed to work with vanes having a recessed underside surface to permit additional bypass exhaust gas flow within the turbocharger when the vanes are actuated in an open position.