Exhaust gas turbocharger for a combustion engine has variable geometry of flow inlet to control turbine blade frequencies below excitation threshold

摘要

An exhaust gas turbocharger for a combustion engine has variable geometry by variation of the flow inlet cross-section using a screen (14) having circumferential blades (16). The first proper frequency of the turbine wheel (3) blades (5) depends on the screen blades and rotation speed and remains less than the excitation frequency.