Nozzle wakes are a common source of fatigue failures in radial inflow turbines. This paper describes an approach to avoiding these problems, without sacrificing performance or manufacturability, by using a small number of carefully designed nozzle vanes and tuning the rotor blades to avoid nozzle passing resonances. Two radial inflow turbines designed via this approach are reviewed, including predicted and measured aerodynamic performance and predicted and measured natural frequencies — all of which are in good agreement. One of the turbines is small, and the other is large, but both have no nozzle passing resonances anywhere in their wide operating ranges, and both have measured efficiencies above 84 percent.

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