6.22. Frame selection (student version)

Written by Marc Budinger (INSA Toulouse), Scott Delbecq (ISAE-SUPAERO) and Félix Pollet (ISAE-SUPAERO), Toulouse, France.

6.22.1. Design graph

The following diagram represents the design graph of the frame selection.

Fig. 6.27 Airframe design graph

Exercise 6.20

• Give the main sizing problems you are able to detect.

• Propose one or multiple solutions (which can request equation manipulation, addition of design variables, addition of constraints)

• Orientate the arrows

• Give equations order, inputs/outputs at each step of this part of sizing procedure

6.22.1.1. Sizing code

import numpy as np

# Specifications
N_arm = 4.0  # [-] Number of arms
N_pro_arm = 1.0  # [-] Number of propellers per arm (1 or 2)

# Reference parameters for scaling laws
sigma_max = (
    280e6 / 4.0
)  # [Pa] Composite max stress (2 reduction for dynamic, 2 reduction for stress concentration)
rho_s = 1700.0  # [kg/m3] Volumic mass of aluminum

# Assumptions
D_pro = 0.3  # [m] Propeller diameter
F_pro_to = 1.0  # [N] Thrust for one propeller during take off

# Design variables

## To be completed

# Equations

## To be completed

%whos

Variable    Type      Data/Info
-------------------------------
D_pro       float     0.3
F_pro_to    float     1.0
N_arm       float     4.0
N_pro_arm   float     1.0
np          module    <module 'numpy' from '/op<...>kages/numpy/__init__.py'>
rho_s       float     1700.0
sigma_max   float     70000000.0