Abstract: High cycle fatigue (HCF) in a turbine wheel of a sector-divided dual volute turbocharger, particularly a turbocharger where the tongue-to-blade gap is as small as from 1-3% of the wheel diameter, is reduced, by locally increasing the volute cross-sectional area just upstream of the tongues. Thereby, it becomes possible to reduce the force function of the exhaust gas pressure onto the turbine wheel blades. Modifying how the pressure presents itself to the wheel reduces blade excitation and, ultimately, HCF of turbine wheels. In another aspect of the invention, the angle of the tongues are modified to direct the exhaust more directly onto the turbine wheel than conventional tongues. It is surprising that this approach not only accomplishes the desired result, but does this without significant loss of turbine stage efficiency.

Abstract: A turbine (10) for a charging device (1) with a turbine housing (100) with a feed duct assembly (200), a turbine outlet duct (110) and a receptacle space (120). The feed duct assembly (200) includes a first feed duct (210) having a first fluid inlet portion (211) and a first fluid outlet portion (212), and a second feed duct (220) having a second fluid inlet portion (221) and a second fluid outlet portion (222). The first fluid outlet portion (212) extends across a first angular range (?1) about the guide installation (400). The second fluid outlet portion (222) extends across a second angular range (?2) about the guide installation (400). The first angular range (?1) is larger than the second angular range (?2). The first fluid inlet portion (211) and the second fluid inlet portion (221) are mutually spaced apart in the circumferential direction (26).

Abstract: A turbine housing for an exhaust turbocharger is configured for receiving a turbine wheel rotatable about an axis. The housing includes an exhaust gas inlet, an exhaust gas outlet pointing in an outlet direction, and a single-flow, spiral exhaust gas routing. The routing has a volute and a volute outlet gap configured so that exhaust gas flows from the volute to the wheel. The routing is fluidically connected to the inlet and is defined by an internal wall of the housing. The volute has a portion which encircles the axis and has a convexity of the internal wall. The convexity, counter to the outlet direction, extends beyond the volute outlet gap. Further, sectional faces, through which the axis runs, each have a volute contour with a straight linear portion. The linear portion, conjointly with the axis, defines an angle facing the outlet that is less than or equal to 90°.

Abstract: A turbine housing for an exhaust turbocharger is configured for receiving a turbine wheel rotatable about an axis. The housing includes an exhaust gas inlet, an exhaust gas outlet pointing in an outlet direction, and a single-flow, spiral exhaust gas routing. The routing has a volute and a volute outlet gap configured so that exhaust gas flows from the volute to the wheel. The routing is fluidically connected to the inlet and is defined by an internal wall of the housing. The volute has a portion which encircles the axis and has a convexity of the internal wall. The convexity, counter to the outlet direction, extends beyond the volute outlet gap. Further, sectional faces, through which the axis runs, each have a volute contour with a straight linear portion. The linear portion, conjointly with the axis, defines an angle facing the outlet that is less than or equal to 90°.

Abstract: High cycle fatigue (HCF) in a turbine wheel of a sector-divided dual volute turbocharger, particularly a turbocharger where the tongue-to-blade gap is as small as from 1-3% of the wheel diameter, is reduced, by locally increasing the volute cross-sectional area just upstream of the tongues. Thereby, it becomes possible to reduce the force function of the exhaust gas pressure onto the turbine wheel blades. Modifying how the pressure presents itself to the wheel reduces blade excitation and, ultimately, HCF of turbine wheels. In another aspect of the invention, the angle of the tongues are modified to direct the exhaust more directly onto the turbine wheel than conventional tongues. It is surprising that this approach not only accomplishes the desired result, but does this without significant loss of turbine stage efficiency.