24 lines
496 B
Python
24 lines
496 B
Python
import numpy as np
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from input.user_input import *
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def Cd_model(fr, re, a_top):
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k_cd = 19.8
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k1 = 1.50 * 10 ** 7
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k2 = 0.86 * 10 ** (-7)
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a_top0 = np.pi / 4 * 1.383 * V_design ** (2/3) # a_top0 for zero-pressure shape
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value = 0.2 * k_cd/fr * (k1/re + k2 * re) * a_top / (a_top0 ** (3/2))
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if value > 1.6:
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value = 1.6
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return value
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c_d = 0.8 # 0.47
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def drag(c_d, rho_air, A_proj, v):
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return 0.5 * c_d * rho_air * A_proj * v ** 2
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