Source code for RCAIDE.Library.Methods.Aerodynamics.Common.Drag.supersonic_wave_drag_volume_sears_haack
# RCAIDE/Library/Methods/Aerodynamics/Common/Drag/supersonic_wave_drag_volume_sears_haack.py
# (c) Copyright 2023 Aerospace Research Community LLC
#
# Created: Jun 2024, M. Clarke
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# IMPORT
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# package imports
import numpy as np
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# Supersonic Wave Drag Due to Volume - Sears Haack
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[docs]
def supersonic_wave_drag_volume_sears_haack(vehicle, mach, scaling_factor, sears_haack_type = 3):
"""Computes the volume drag
Assumptions:
Basic fit
Source:
Sieron, Thomas R., et al. Procedures and design data for the formulation of aircraft
configurations. WRIGHT LAB WRIGHT-PATTERSON AFB OH, 1993. Page B-3
Args:
vehicle.
total_length [m]
maximum_cross_sectional_area [m^2]
reference_area [m^2]
Returns:
vehicle_wave_drag [Unitless]
"""
L = vehicle.total_length
Amax = vehicle.maximum_cross_sectional_area
S = vehicle.reference_area
rmax = np.sqrt(Amax/np.pi)
d = rmax*2
if sears_haack_type == 3:
# Compute drag from Sears-Haack type III body
# Source formula uses front projected area as a reference
CD = 3/2*np.pi*np.pi*(d/L)*(d/L)*Amax/S
else:
raise NotImplementedError # can add other Sears-Haack types here
# Scale to account for non-ideal shaping
CD_scaled = CD*scaling_factor
return CD_scaled
