RCAIDE.Library.Methods.Powertrain.Propulsors.Turbofan.compute_thurst.compute_thrust#
- compute_thrust(turbofan, conditions)[source]#
Computes thrust and other performance metrics for a turbofan engine.
- Parameters:
turbofan (RCAIDE.Library.Components.Propulsors.Turbofan) –
- Turbofan engine component with the following attributes:
- tagstr
Identifier for the turbofan
- reference_temperaturefloat
Reference temperature for mass flow scaling [K]
- reference_pressurefloat
Reference pressure for mass flow scaling [Pa]
- compressor_nondimensional_massflowfloat
Non-dimensional mass flow parameter [kg·√K/(s·Pa)]
- SFC_adjustmentfloat
Adjustment factor for specific fuel consumption
conditions (RCAIDE.Framework.Mission.Common.Conditions) –
- Flight conditions with:
- freestreamData
- Freestream properties
- isentropic_expansion_factornumpy.ndarray
Ratio of specific heats (gamma)
- velocitynumpy.ndarray
Freestream velocity [m/s]
- speed_of_soundnumpy.ndarray
Speed of sound [m/s]
- mach_numbernumpy.ndarray
Freestream Mach number
- pressurenumpy.ndarray
Freestream pressure [Pa]
- gravitynumpy.ndarray
Gravitational acceleration [m/s²]
- specific_heat_at_constant_pressurenumpy.ndarray
Specific heat at constant pressure [J/(kg·K)]
- energy.propulsors[turbofan.tag]Data
- Turbofan-specific conditions
- fuel_to_air_rationumpy.ndarray
Fuel-to-air ratio
- total_temperature_referencenumpy.ndarray
Reference total temperature [K]
- total_pressure_referencenumpy.ndarray
Reference total pressure [Pa]
- fan_nozzle_exit_velocitynumpy.ndarray
Fan nozzle exit velocity [m/s]
- fan_nozzle_static_pressurenumpy.ndarray
Fan nozzle static pressure [Pa]
- fan_nozzle_area_rationumpy.ndarray
Fan nozzle area ratio
- core_nozzle_exit_velocitynumpy.ndarray
Core nozzle exit velocity [m/s]
- core_nozzle_static_pressurenumpy.ndarray
Core nozzle static pressure [Pa]
- core_nozzle_area_rationumpy.ndarray
Core nozzle area ratio
- flow_through_corenumpy.ndarray
Fraction of flow through core
- flow_through_fannumpy.ndarray
Fraction of flow through fan
- bypass_rationumpy.ndarray
Bypass ratio
- throttlenumpy.ndarray
Throttle setting [0-1]
- Returns:
- Results are stored in conditions.energy.propulsors[turbofan.tag]:
- thrustnumpy.ndarray
Total thrust force [N]
- fan_thrustnumpy.ndarray
Thrust from fan stream [N]
- core_thrustnumpy.ndarray
Thrust from core stream [N]
- thrust_specific_fuel_consumptionnumpy.ndarray
Thrust specific fuel consumption [kg/(N·hr)]
- non_dimensional_thrustnumpy.ndarray
Non-dimensional thrust
- core_mass_flow_ratenumpy.ndarray
Core mass flow rate [kg/s]
- fuel_flow_ratenumpy.ndarray
Fuel flow rate [kg/s]
- powernumpy.ndarray
Power output [W]
- specific_impulsenumpy.ndarray
Specific impulse [s]
- Return type:
None
Notes
This function implements a thermodynamic model for a turbofan engine to calculate thrust, fuel consumption, and other performance metrics. It computes thrust from both the core and fan streams, accounting for momentum and pressure forces.
- Major Assumptions
Perfect gas behavior
Thrust is calculated from momentum and pressure forces at the nozzle exits
Theory The non-dimensional thrust components are calculated as:
\[ \begin{align}\begin{aligned}F_{nd,fan} = \phi_{fan} \cdot (\gamma \cdot M_0^2 \cdot (V_{fan}/V_0 - 1) + A_{fan} \cdot (P_{fan}/P_0 - 1))\\F_{nd,core} = \phi_{core} \cdot (\gamma \cdot M_0^2 \cdot (V_{core}/V_0 - 1) + A_{core} \cdot (P_{core}/P_0 - 1))\end{aligned}\end{align} \]- where:
\(\phi_{fan}\) is the flow through fan fraction
\(\phi_{core}\) is the flow through core fraction
\(\gamma\) is the ratio of specific heats
\(M_0\) is the freestream Mach number
\(V_{fan}\) is the fan nozzle exit velocity
\(V_{core}\) is the core nozzle exit velocity
\(V_0\) is the freestream velocity
\(A_{fan}\) is the fan nozzle area ratio
\(A_{core}\) is the core nozzle area ratio
\(P_{fan}\) is the fan nozzle static pressure
\(P_{core}\) is the core nozzle static pressure
\(P_0\) is the freestream pressure
The specific thrust is then:
\[F_{sp} = \frac{F_{nd,fan} + F_{nd,core}}{\gamma \cdot M_0}\]References
[1] Cantwell, B., “AA283 Course Notes”, Stanford University. https://web.stanford.edu/~cantwell/AA283_Course_Material/