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TECROD engineering dashboard V1.5

TECROD Steam Turbine Preliminary Design Tool

Mollier-based educational estimator for impulse turbine staging

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Educational use only. V1.5 is an educational preliminary estimator. Steam properties may be entered manually from a Mollier chart or estimated using a simplified ideal-gas steam approximation. Not for final design, certification, or safety-critical decisions.

Future versions may replace the simplified estimator with local IAPWS-IF97 steam-property calculations or a precomputed steam-properties grid.

Mollier h-s diagram (schematic)

Diameter comparison

Diameter U Delta h stage Estimated stages Rounded

Engineering interpretation

The Mollier chart gives the available enthalpy drop between inlet and exhaust conditions.
For an ideal turbine expansion, entropy is approximately constant.
Real turbines have losses, so the actual outlet state has higher entropy and lower useful enthalpy drop.
The stage enthalpy drop depends strongly on peripheral speed, which depends on diameter and RPM.
A larger mean diameter increases blade speed and can reduce the estimated number of stages.
Tangential velocity components drive shaft work through Euler's turbine equation, while axial velocity is essential for carrying mass flow through the stage.
This tool is intended for early learning, visualization, and preliminary reasoning. Final turbine design requires validated steam properties, detailed velocity triangles, stress analysis, vibration evaluation, manufacturing constraints, and physical validation.

Future versions may replace the simplified estimator with local IAPWS-IF97 steam-property calculations or a precomputed steam-properties grid.