aerosandbox.library.propulsion_propeller#

Module Contents#

Functions#

propeller_shaft_power_from_thrust(thrust_force, ...[, ...])

Using dynamic disc actuator theory, gives the shaft power required to generate

mass_hpa_propeller(diameter, max_power[, ...])

Returns the estimated mass of a propeller assembly for low-disc-loading applications (human powered airplane, paramotor, etc.)

mass_gearbox(power, rpm_in, rpm_out)

Estimates the mass of a gearbox.
aerosandbox.library.propulsion_propeller.propeller_shaft_power_from_thrust(thrust_force, area_propulsive, airspeed, rho, propeller_coefficient_of_performance=0.8)[source]#

Using dynamic disc actuator theory, gives the shaft power required to generate a certain amount of thrust.

Source: https://web.mit.edu/16.unified/www/FALL/thermodynamics/notes/node86.html

Parameters:

  • thrust_force – Thrust force [N]

  • area_propulsive – Total disc area of all propulsive surfaces [m^2]

  • airspeed – Airspeed [m/s]

  • rho – Air density [kg/m^3]

  • propeller_coefficient_of_performance – propeller coeff. of performance (due to viscous losses) [unitless]

Returns:

Shaft power [W]

aerosandbox.library.propulsion_propeller.mass_hpa_propeller(diameter, max_power, include_variable_pitch_mechanism=False)[source]#

Returns the estimated mass of a propeller assembly for low-disc-loading applications (human powered airplane, paramotor, etc.)

Parameters:

  • diameter – diameter of the propeller [m]

  • max_power – maximum power of the propeller [W]

  • include_variable_pitch_mechanism – boolean, does this propeller have a variable pitch mechanism?

Returns:

estimated weight [kg]

aerosandbox.library.propulsion_propeller.mass_gearbox(power, rpm_in, rpm_out)[source]#

Estimates the mass of a gearbox.

Based on data from NASA/TM-2009-215680, available here:

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20090042817.pdf

R^2 = 0.92 to the data.

To quote this document:

“The correlation was developed based on actual weight data from over fifty rotorcrafts, tiltrotors, and turboprop aircraft.”

Data fits in the NASA document were thrown out and refitted to extrapolate more sensibly; see:

C:ProjectsGitHubAeroSandboxstudiesGearboxMassFits

Parameters:

  • power – Shaft power through the gearbox [W]

  • rpm_in – RPM of the input to the gearbox [rpm]

  • rpm_out – RPM of the output of the gearbox [rpm]

Returns:

Estimated mass of the gearbox [kg]