My experimental program for smoothing and extending turbine maps is a derivative of Smooth T 9.
Smooth T generates smooth turbine maps for use with gas turbine performance programs. The input can be calculated or measured data, map tables you use with your favourite performance program, or a graphical presentation of the map.
I begun the development of Smooth T in the early 1990's. The latest publicly available version has been released in August 2021 by GasTurb GmbH. The changes from the predecessor of this program are based on the ideas which I published in 2020:
Turbine Map Extension – Theoretical Considerations and Practical Advice
Joachim Kurzke
Journal of the Global Power and Propulsion Society. 4: 176-189
GasTurb is a trademark of GasTurb GmbH, Aachen, Germany