ABSTRACT
The current paper investigates the application of 1D performance models for external circular volutes. The aim is to substitute the volute in computationally expensive CFD calculations with lower order models during intermediate design iterations. The CFD predicted volute performance, available to the authors from designs of various stages including both vaned and vaneless diffusers, have been used as benchmarks. The conventional low order models have been examined and, where appropriate, further developments have been made. The final set of the models proposed in the paper are applicable to stages with both vanes and vaneless diffusers.
