RCAIDE.Library.Methods.Powertrain.Propulsors.Turbojet.design_turbojet

design_turbojet

design_turbojet(turbojet)

Designs a turbojet engine by computing performance properties and sizing components based on design conditions.

Parameters:

turbojet (Turbojet) –

Turbojet engine object containing design parameters and components

• design_mach_numberfloat

  Design point Mach number [-]

• design_altitudefloat

  Design point altitude [m]

• design_isa_deviationfloat

  ISA temperature deviation [K]

• working_fluidGas

  Working fluid object for gas properties

• Components:

  • ram : Ram

  • inlet_nozzle : Compression_Nozzle

  • low_pressure_compressor : Compressor

  • high_pressure_compressor : Compressor

  • combustor : Combustor

  • high_pressure_turbine : Turbine

  • low_pressure_turbine : Turbine

  • core_nozzle : Supersonic_Nozzle

Returns:

Updates turbojet object attributes in-place:

• mass_flow_rate_designfloat

  Design core mass flow rate [kg/s]

• design_core_massflowfloat

  Core mass flow at design point [kg/s]

Return type:

None

Notes

This function performs the following steps:

1. Computes atmospheric conditions at design point

2. Sets up freestream conditions

3. Links and analyzes flow through each component:

   • Ram inlet

   • Inlet nozzle

   • Low pressure compressor

   • High pressure compressor

   • Combustor

   • High pressure turbine

   • Low pressure turbine

   • Core nozzle

4. Sizes the core based on design thrust requirements

5. Computes static sea level performance

Major Assumptions

• Quasi-one-dimensional flow

• Each component operates in steady state

• Perfect gas behavior in non-combustion sections

• US Standard Atmosphere 1976 model

• Earth gravity model

• Design point defines core sizing

Theory The design process follows standard gas turbine design principles:

\[ \begin{align}\begin{aligned}\text{Mass flow continuity: } \dot{m}_{in} = \dot{m}_{out}\\\text{Power Balance: } W_{compressor} = W_{turbine}\\\text{Core sizing: } \dot{m}_{core} = \frac{F_{design}}{F_{sp} a_0}\end{aligned}\end{align} \]

where:

• \(F_{design}\) is the design thrust

• \(F_{sp}\) is the specific thrust

• \(a_0\) is the freestream speed of sound

References

[1] Mattingly, J. D., “Elements of Gas Turbine Propulsion”, McGraw-Hill, 1996 [2] Walsh, P. P., Fletcher, P., “Gas Turbine Performance”, Blackwell Science, 2004

See also

RCAIDE.Library.Methods.Powertrain.Propulsors.Turbojet.compute_turbojet_performance, RCAIDE.Library.Methods.Powertrain.Propulsors.Turbojet.size_core, RCAIDE.Library.Methods.Powertrain.Propulsors.Common.compute_static_sea_level_performance