RCAIDE.Library.Methods.Powertrain.Propulsors.Turboprop.size_core

size_core

size_core(turboprop, conditions)

Sizes the core flow for a turboprop engine at the design condition.

Parameters:

• turboprop (RCAIDE.Library.Components.Propulsors.Turboprop) –

  Turboprop engine component with the following attributes:

  • tagstr

    Identifier for the turboprop

  • reference_temperaturefloat

    Reference temperature for mass flow scaling [K]

  • reference_pressurefloat

    Reference pressure for mass flow scaling [Pa]

  • design_thrustfloat

    Design thrust at the design point [N]

• conditions (RCAIDE.Framework.Mission.Common.Conditions) –

  Flight conditions with:

  • energy.propulsors[turboprop.tag]Data

    Turboprop-specific conditions

    • total_temperature_referencenumpy.ndarray

      Reference total temperature [K]

    • total_pressure_referencenumpy.ndarray

      Reference total pressure [Pa]

    • throttlefloat

      Throttle setting [0-1]

    • thrust_specific_fuel_consumptionnumpy.ndarray

      Thrust specific fuel consumption [kg/(N·s)]

    • non_dimensional_thrustnumpy.ndarray

      Non-dimensional thrust

Returns:

Results are stored in the turboprop object:

• TSFCfloat

  Thrust specific fuel consumption [kg/(N·s)]

• design_mass_flow_ratefloat

  Core mass flow rate at design point [kg/s]

• compressor_nondimensional_massflowfloat

  Non-dimensional mass flow parameter [kg·√K/(s·Pa)]

Return type:

None

Notes

This function determines the core mass flow rate required to produce the design thrust at the specified design conditions. It uses the non-dimensional thrust parameter to scale the mass flow appropriately.

Major Assumptions

• Perfect gas behavior

• Turboprop engine with conventional architecture

• Design point is at maximum throttle (throttle = 1.0)

Theory The core mass flow rate is calculated from the design thrust and non-dimensional thrust:

\[\dot{m}_{core} = \frac{F_{design} \cdot \text{throttle}}{F_{sp}}\]

The non-dimensional mass flow parameter is then calculated:

\[\dot{m}_{hc} = \frac{\dot{m}_{core}}{\sqrt{\frac{T_{ref}}{T_{t,ref}}} \cdot \frac{P_{t,ref}}{P_{ref}}}\]

References

[1] Mattingly, J.D., “Elements of Gas Turbine Propulsion”, 2nd Edition, AIAA Education Series, 2005.

See also

RCAIDE.Library.Methods.Powertrain.Propulsors.Turboprop.compute_thrust