I begun the development of Smooth C in the early 1990's. The latest publicly available version Smooth C 9 has been released in August 2021 by GasTurb GmbH. The changes from the predecessor of this program are based on the ideas I presented at the ISABE conference 2019 in Canberra, Australia:

Generating Compressor Maps To Simulate Starting And Windmilling
Joachim Kurzke
ISABE-2019-24299

At the GPPS Conference October 17-19, 2023 in Hong Kong, China,  I presented another publication on the extension of compressor maps to pressure ratios less than one and very low speeds:

An Enhanced Compressor Map Extension Method Suited for Spool Speeds Down to 1%
Joachim Kurzke
Journal of the Global Power and Propulsion Society. 8: 215-226, 2024

The methods described in this paper have been developed with my experimental derivative of Smooth C 9.

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