propeller.py

class openconcept.propulsion.propeller.SimplePropeller(**kwargs)

Bases: Group

This propeller is representative of a constant-speed prop.

The technology may be old. A general, empirical efficiency map for a constant speed turboprop is used for most of the flight regime. A static thrust coefficient map (from Raymer) is used for advance ratio < 0.2 (low speed). Linear interpolation from static thrust to dynamic thrust tables at J = 0.1 to 0.2.

Inputs:

  • shaft_power_in (float) – Shaft power driving the prop (vector, W)

  • diameter (float) – Prop diameter (scalar, m)

  • rpm (float) – Prop RPM (vector, RPM)

  • fltcond|rho (float) – Air density (vector, kg/m**3)

  • fltcond|Utrue (float) – True airspeed (vector, m/s)

Outputs:

  • thrust (float) – Propeller thrust (vector, N)

  • component_weight (float) – Prop weight (scalar, kg)

Options:

  • num_nodes (int) – Number of analysis points to run (sets vec length; default 1)

  • num_blades (int) – Number of propeller blades (default 4)

  • design_cp (float) – Design cruise power coefficient (cp)

  • design_J (float) – Design advance ratio (J)