# RCAIDE/Methods/Performance/compute_load_and_trim_diagram.py
#
#
# Created: Dec 2024, M. Clarke
# ----------------------------------------------------------------------------------------------------------------------
# IMPORT
# ----------------------------------------------------------------------------------------------------------------------
# RCAIDE imports
import RCAIDE
from RCAIDE.Framework.Core import Data, Units
from RCAIDE.Library.Methods.Mass_Properties.estimate_maximum_landing_weight import estimate_maximum_landing_weight
from RCAIDE.Library.Methods.Mass_Properties.Center_of_Gravity import compute_vehicle_center_of_gravity
from RCAIDE.Library.Mission.Common.Pre_Process import geometry, mass_properties
import pandas as pd
# Pacakge imports
import numpy as np
from copy import deepcopy
#------------------------------------------------------------------------------
# compute_load_and_trim_diagram
#------------------------------------------------------------------------------
[docs]
def compute_load_and_trim_diagram(mission = None, cruise_segment_tag = "cruise",discretization = 5):
"""
Computes the loading dragram of an aircraft
Parameters
--------
Notes
-----
# total number of sumulations = 2 * discretization ^ N
# where 2: is for the loading and unloading cases
# and N is the number of object types i.e cabin,cargo and fuel
"""
#------------------------------------------------------------------------
# Remove Takeoff mass
#------------------------------------------------------------------------
for segment in mission.segments:
segment.analyses.vehicle.mass_properties.takeoff = None
segment.analyses.geometry.settings.compute_fuel_volume = True
segment.analyses.weights.print_weight_analysis_report = True
segment.analyses.weights.settings.run_center_of_gravity_analysis = True
segment.analyses.weights.settings.overwrite_center_of_gravity = True
segment.analyses.weights.settings.run_moments_of_inertia_analysis = True
segment.analyses.stability.print_stability_analysis_report = True
segment.analyses.stability.settings.compute_neutral_point = True
#------------------------------------------------------------------------
# Check Input Args
#------------------------------------------------------------------------
vehicle = mission.segments[cruise_segment_tag].analyses.vehicle
cabin_class_check = False
for fuselage in vehicle.fuselages:
for cabin in fuselage.cabins:
for _ in cabin.classes:
cabin_class_check = True
for wing in vehicle.wings:
if isinstance(wing, RCAIDE.Library.Components.Wings.Blended_Wing_Body):
for cabin in wing.cabins:
for _ in cabin.classes:
cabin_class_check = True
if cabin_class_check == False:
raise AttributeError('At least one cabin class must be defined to create Aircraft mass-C.G. envelope ')
#------------------------------------------------------------------------
# Run Baseline mission
#------------------------------------------------------------------------
results = mission.evaluate()
# compute mass properties of aircraft to get weight distribution
vehicle_0 = mission.segments[cruise_segment_tag].analyses.vehicle
x_cg_0 = mission.segments[cruise_segment_tag].analyses.vehicle.mass_properties.center_of_gravity
weight_breakdown = mission.segments[cruise_segment_tag].analyses.vehicle.mass_properties.weight_breakdown
neutral_point_0 = mission.segments[cruise_segment_tag].analyses.vehicle.neutral_point
W_PAX = weight_breakdown.payload.passengers
PAX = vehicle_0.number_of_passengers
W_PAX_per_pax = W_PAX / PAX
MTOW = vehicle_0.mass_properties.max_takeoff
MZFW = vehicle_0.mass_properties.max_zero_fuel
FUEL = vehicle_0.mass_properties.max_fuel
PLD = vehicle_0.mass_properties.max_payload
vehicle_0.mass_properties.payload = PLD
PLD_per_pax = (weight_breakdown.payload.passengers + weight_breakdown.payload.baggage) / PAX
OEW = vehicle_0.mass_properties.operating_empty
if mission.segments[cruise_segment_tag].analyses.weights.propulsion_architecture == 'Cryogenic':
MLW = (vehicle_0.mass_properties.max_takeoff - 0.65 * vehicle_0.mass_properties.max_fuel)
else:
MLW = estimate_maximum_landing_weight(MTOW)
W_CARGO = 0
m_c = []
for cargo_bay in vehicle_0.cargo_bays:
W_CARGO += cargo_bay.mass_properties.mass
m_c.append(cargo_bay.mass_properties.mass)
cargo_bay_ratio = np.array(m_c) / sum(np.array(m_c))
W_CARGO += PLD-W_PAX
m_f = []
for network in vehicle_0.networks:
for fuel_line in network.fuel_lines:
for fuel_tank in fuel_line.fuel_tanks:
m_f.append(fuel_tank.fuel.mass_properties.mass)
fuel_tank_ratio = np.array(m_f) / sum(np.array(m_f))
#------------------------------------------------------------------------
# Compute Loading Points
#------------------------------------------------------------------------
# determine number is weight simulations
# total number of sumulations = 2 * discretization ^ N
# where 2: is for the loading and unloading cases
# and N is the number of object types i.e cabin,cargo and fuel
total_sims = 2 * discretization **3
# define discretization
percent_fuel = np.linspace(0.0, 1,discretization)
percent_pax = np.linspace(0.0, 1,discretization)
percent_cargo = np.linspace(0.0, 1,discretization)
percent_weight = np.linspace(0.0, 1,discretization)
percent_cg_shift = np.linspace(0.8,1.2,discretization)
filling_order = ['ascending','descending']
# create empty data structures
RES = Data()
RES.loading_results = Data()
RES.trim_results = Data()
RES.discretization = discretization
RES.loading_results.mass = np.zeros((2,discretization,discretization,discretization))
RES.loading_results.CG_location = np.zeros((2,discretization,discretization,discretization))
RES.loading_results.LEMAC_location = np.zeros((2,discretization,discretization,discretization))
RES.loading_results.CG_percent_of_LEMAC_location= np.zeros((2,discretization,discretization,discretization))
RES.loading_results.static_margin = np.zeros((2,discretization,discretization,discretization))
RES.percent_cargo = np.zeros((2,discretization,discretization,discretization))
RES.percent_pax = np.zeros((2,discretization,discretization,discretization))
RES.percent_cargo = np.zeros((2,discretization,discretization,discretization))
RES.trim_results.neutral_point = np.zeros((discretization,discretization))
RES.trim_results.static_margin = np.zeros((discretization,discretization))
RES.trim_results.mass = np.zeros((discretization,discretization))
RES.trim_results.LEMAC_location = np.zeros((discretization,discretization))
RES.trim_results.CG_percent_of_LEMAC_location = np.zeros((discretization,discretization))
RES.MTOW = MTOW
RES.OEW = OEW
RES.MLW = MLW
#============================================================================================
# Load Diagram Data
#============================================================================================
counter = 0
for f_o in range(len(filling_order)):
for p_i in range(len(percent_pax)):
for c_i in range(len(percent_cargo)):
for f_i in range(len(percent_fuel)):
#------------------------------------------------------------------------
# Reset all weights to 0
#------------------------------------------------------------------------
vehicle = deepcopy(vehicle_0)
vehicle.mass_properties.max_zero_fuel = MZFW
vehicle.mass_properties.takeoff = None
vehicle.mass_properties.payload = 0
vehicle.mass_properties.cargo = 0
vehicle.number_of_passengers = 1
vehicle.mass_properties.fuel = 0
for network in vehicle.networks:
for fuel_line in network.fuel_lines:
for fuel_tank in fuel_line.fuel_tanks:
fuel_tank.fuel.mass_properties.mass = 0
for cargo_bay in vehicle.cargo_bays:
cargo_bay.mass_properties.mass = 0
for fuselage in vehicle.fuselages:
for cabin in fuselage.cabins:
cabin.number_of_passengers = 0
for wing in vehicle.wings:
if isinstance(wing, RCAIDE.Library.Components.Wings.Blended_Wing_Body):
for cabin in wing.cabins:
cabin.number_of_passengers = 0
#------------------------------------------------------------------------
# Update Passengers
#------------------------------------------------------------------------
# run weights analysis and store results
vehicle.number_of_passengers = pax = 1 if p_i == 0 else int(percent_pax[p_i] * PAX )
for fuselage in vehicle.fuselages:
for cabin in fuselage.cabins:
cabin.filled_seats_arrangement = filling_order[f_o]
pax = 1 if p_i == 0 else int(percent_pax[p_i] * vehicle_0.fuselages[fuselage.tag].cabins[cabin.tag].number_of_passengers)
cabin_mass = 1E-6 if p_i == 0 else pax * W_PAX_per_pax
cabin.number_of_passengers = pax
cabin.mass_properties.mass = cabin_mass
for wing in vehicle.wings:
if isinstance(wing, RCAIDE.Library.Components.Wings.Blended_Wing_Body):
for cabin in wing.cabins:
cabin.filled_seats_arrangement = filling_order[f_o]
pax = 1 if p_i == 0 else int(percent_pax[p_i] * vehicle_0.wings[wing.tag].cabins[cabin.tag].number_of_passengers)
cabin_mass = 1E-6 if p_i == 0 else pax * W_PAX_per_pax
cabin.number_of_passengers = pax
cabin.mass_properties.mass = cabin_mass
#------------------------------------------------------------------------
# Update Cargo
#------------------------------------------------------------------------
for cargo_bay_i , cargo_bay in enumerate(vehicle.cargo_bays):
cargo_bay.mass_properties.mass = percent_cargo[c_i] * W_CARGO * cargo_bay_ratio[cargo_bay_i]
vehicle.mass_properties.cargo = percent_cargo[c_i] * W_CARGO
vehicle.mass_properties.payload = (W_PAX_per_pax) *vehicle.number_of_passengers + vehicle.mass_properties.cargo
# loop through fuel tanks
for network in vehicle.networks:
for fuel_line in network.fuel_lines:
for fuel_tank_i , fuel_tank in enumerate(fuel_line.fuel_tanks):
fuel_tank.fuel.mass_properties.mass = percent_fuel[f_i] * FUEL * fuel_tank_ratio[fuel_tank_i]
# run weights analysis and store results
vehicle.mass_properties.fuel = percent_fuel[f_i] * FUEL
#------------------------------------------------------------------------
# run weights analysis and store results
#------------------------------------------------------------------------
counter = compute_aircraft_load_data_point(vehicle,cruise_segment_tag,RES,counter,
total_sims, neutral_point_0,percent_pax[p_i], percent_cargo[c_i], percent_fuel[f_i],
f_o,p_i, c_i, f_i)
#============================================================================================
# Trim Diagram Data
#============================================================================================
total_sims = discretization ** 2
counter = 0
for w_i in range(discretization):
for c_g_i in range(discretization):
vehicle = deepcopy(vehicle_0)
# Aircraft-Level Properties
vehicle.mass_properties.payload = PLD_per_pax if w_i == 0 else percent_weight[w_i] * PLD
vehicle.mass_properties.cargo = percent_weight[w_i] * W_CARGO
vehicle.mass_properties.center_of_gravity[0][0] = x_cg_0[0][0] * percent_cg_shift[c_g_i]
vehicle.number_of_passengers = 1 if w_i == 0 else int(vehicle_0.number_of_passengers * percent_weight[w_i])
vehicle.mass_properties.fuel = percent_weight[w_i] * FUEL
for network in vehicle.networks:
for fuel_line in network.fuel_lines:
for fuel_tank in fuel_line.fuel_tanks:
fuel_tank.fuel.mass_properties.mass = 0
for cargo_bay in vehicle.cargo_bays:
cargo_bay.mass_properties.mass = 0
for fuselage in vehicle.fuselages:
for cabin in fuselage.cabins:
cabin.number_of_passengers = 0
for wing in vehicle.wings:
if isinstance(wing, RCAIDE.Library.Components.Wings.Blended_Wing_Body):
for cabin in wing.cabins:
cabin.number_of_passengers = 0
#------------------------------------------------------------------------
# Update Passengers
#------------------------------------------------------------------------
# run weights analysis and store results
vehicle.number_of_passengers = 1 if w_i == 0 else int(percent_weight[w_i] * PAX )
for fuselage in vehicle.fuselages:
for cabin in fuselage.cabins:
pax = 1 if w_i == 0 else int(percent_weight[w_i] * vehicle_0.fuselages[fuselage.tag].cabins[cabin.tag].number_of_passengers)
cabin.number_of_passengers = pax
for wing in vehicle.wings:
if isinstance(wing, RCAIDE.Library.Components.Wings.Blended_Wing_Body):
for cabin in wing.cabins:
pax = 1 if w_i == 0 else int(percent_weight[w_i] * vehicle_0.wings[wing.tag].cabins[cabin.tag].number_of_passengers)
cabin.number_of_passengers = pax
#------------------------------------------------------------------------
# Update Cargo
#------------------------------------------------------------------------
for cargo_bay in vehicle.cargo_bays:
cargo_bay.mass_properties.mass = percent_cargo[w_i] * W_CARGO * cargo_bay_ratio[cargo_bay_i]
vehicle.mass_properties.cargo = percent_cargo[w_i] * W_CARGO
vehicle.mass_properties.payload = (W_PAX_per_pax) *vehicle.number_of_passengers + vehicle.mass_properties.cargo
# loop through fuel tanks
for network in vehicle.networks:
for fuel_line in network.fuel_lines:
for fuel_tank in fuel_line.fuel_tanks:
fuel_tank.fuel.mass_properties.mass = percent_fuel[w_i] * FUEL * fuel_tank_ratio[fuel_tank_i]
# run weights analysis and store results
vehicle.mass_properties.fuel = percent_fuel[w_i] * FUEL
cargo_weight = percent_cargo[w_i] * W_CARGO
pax_weight = percent_fuel[w_i] * W_PAX
fuel_weight = percent_fuel[w_i] * FUEL
vehicle.mass_properties.takeoff = OEW + pax_weight + cargo_weight + fuel_weight
# Run aerodynamic analysis
counter = compute_aircraft_trim_data_point(vehicle,cruise_segment_tag,RES,counter,total_sims,neutral_point_0,w_i,c_g_i)
return RES
[docs]
def compute_aircraft_load_data_point(vehicle,cruise_segment_tag,RES,counter,
total_sims,neutral_point,percent_pax, percent_cargo, percent_fuel,
f_o,p_i,c_i,f_i):
# run geometry and mass properties analyes
center_of_gravity, mass, moment, _ = compute_vehicle_center_of_gravity(vehicle,
centre_of_gravity_df = pd.DataFrame(columns=[ "Component", "Mass (kg)", "CG x (m)", "CG y (m)","CG z (m)"]),
overwrite_center_of_gravity = True,
segment=None,
verbose=False)
# store results
RES.loading_results.CG_location[f_o,p_i,c_i,f_i] = center_of_gravity[0][0]
RES.loading_results.mass[f_o,p_i,c_i,f_i] = mass[0]
RES.loading_results.LEMAC_location[f_o,p_i,c_i,f_i] = vehicle.LEMAC
RES.loading_results.static_margin[f_o,p_i,c_i,f_i] = (neutral_point - center_of_gravity[0][0]) /vehicle.reference_chord
RES.loading_results.CG_percent_of_LEMAC_location[f_o,p_i,c_i,f_i] = (RES.loading_results.CG_location[f_o,p_i,c_i,f_i] - vehicle.LEMAC) / vehicle.reference_chord
print('***************************************')
print('Loading Diagram Data Point: ' + str(counter+1) + ' of ' + str(total_sims))
print('Mass : ', RES.loading_results.mass[f_o,p_i,c_i,f_i])
print('OEW : ', vehicle.mass_properties.operating_empty)
print('Percent Fuel : ', percent_fuel*100 )
print('Percent Cargo : ', percent_cargo*100 )
print('Percent Pax : ', percent_pax*100 )
print('Ref. Chord : ', vehicle.reference_chord)
print('LEMAC : ', vehicle.LEMAC )
print('Center of Gravity Location: ', RES.loading_results.CG_location[f_o,p_i,c_i,f_i] )
print('Neutral Point Location : ', neutral_point )
print('LEMAC : ', RES.loading_results.LEMAC_location[f_o,p_i,c_i,f_i] )
print('CG as % LEMAC : ', RES.loading_results.CG_percent_of_LEMAC_location[f_o,p_i,c_i,f_i] )
print('***************************************')
counter += 1
return counter
[docs]
def compute_aircraft_trim_data_point(vehicle,cruise_segment_tag,RES,
counter,total_sims,neutral_point,w_i,c_g_i):
# store results
RES.trim_results.neutral_point[w_i,c_g_i] = neutral_point
RES.trim_results.static_margin[w_i,c_g_i] = (RES.trim_results.neutral_point[w_i,c_g_i] - vehicle.mass_properties.center_of_gravity[0][0]) /vehicle.reference_chord
RES.trim_results.mass[w_i,c_g_i] = vehicle.mass_properties.takeoff
RES.trim_results.LEMAC_location[w_i,c_g_i] = vehicle.LEMAC
RES.trim_results.CG_percent_of_LEMAC_location[w_i,c_g_i] = (vehicle.mass_properties.center_of_gravity[0][0] - vehicle.LEMAC) / vehicle.reference_chord
print('***************************************')
print('Trim Diagram Data Point : ' + str(counter+1) + ' of ' + str(total_sims))
print('Center of Gravity : ',vehicle.mass_properties.center_of_gravity[0][0])
print('OEW : ', vehicle.mass_properties.operating_empty)
print('% LEMAC Location : ', RES.trim_results.LEMAC_location[w_i,c_g_i] )
print('Neutral Point : ',RES.trim_results.neutral_point[w_i,c_g_i])
print('Static Margin : ',RES.trim_results.static_margin[w_i,c_g_i])
print('Mass : ',RES.trim_results.mass[w_i,c_g_i] )
print('CG as % LEMAC : ', RES.trim_results.CG_percent_of_LEMAC_location[w_i,c_g_i] )
print('***************************************')
counter += 1
return counter
