STELLA is a multi-stage row by row throughflow analysis program that predicts performance and efficiency of axial flow steam turbines under arbitrary flow conditions. The designer is able to modify the geometry of an existing flow path to improve either the total output or efficiency of a multi-stage turbine.

Why use STELLA?

  • Evaluate effects of plant operating parameters such as mass flow, condenser pressure, extraction flows, etc. on turbine efficiency
  • Identify sources of turbine efficiency degradation to determine most cost effective repair strategies
  • Perform more accurate cost-benefit analyses of proposed replacement steam path components during the procurement phase
  • Improve effectiveness of long range turbine overhaul planning by predicting effect of progressive seal and blade component damage
  • As a design tool, for building a new steam flow path
  • simultaneously solving ofy flow energy equation, conservation of mass flow, and the radial equilibrium equation.


  • User friendly interface
  • Rapid solution generation
  • Seventeen streamtubes arranged radially from hub to tip of each blading element account for spanwise variations in blade profile and flow conditions
  • Permits three dimensional flowpaths to be effectively analyzed in two dimensions.
  • Graphical representations of flowpath geometry, and calculated output parameters (e.g., section efficiency) are displayed as color contours superimposed on the geometry.
  • Empirical loss coefficients (Craig, Cox and Chen), industry standards, are incorporated into STELLA to quantify and distribute blade profile losses, incidence losses, surface roughness losses, Reynolds and mach number losses, and secondary losses.
  • Overall stage losses due to seal leakages, wetness, and tiewire blockage are accounted for.
  • The critical relationships between enthalpy, entropy, pressure, specific volume, and wetness are maintained throughout the iterative process using the ASME steam table

Additional Information

Download the STELLA Brochure (pdf format)
Download the STELLA Demo