125 lines
2.5 KiB
Python
125 lines
2.5 KiB
Python
from matplotlib import pyplot as plot
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import numpy as np
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temperatures = []
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# Standard-Atmosphärendruck [Pa]
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g_p0 = 101325
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# spezifischen Gaskonstante R_S = R/M = 287,058 J/(kg*K) für trockene Luft
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g_RS = 287.54
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# CW-Wert und Stirnfläche
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c_val_id3 = 0.267
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area_id3 = 2.360 # m^3
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car_list = [
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{
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"car": "VW id.3",
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"cw": 0.267,
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"area": 2.360
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},
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{
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"car": "Tesla Model Y LR AWD",
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"cw": 0.23,
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"area": 2.518
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},
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{
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"car": "Tesla Model 3 LR AWD",
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"cw": 0.23,
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"area": 2.220
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},
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{
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"car": "Polestar 2",
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"cw": 0.278,
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"area": 2.480
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},
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{
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"car": "Renault Zoe",
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"cw": 0.33,
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"area": 2.27
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},
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{
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"car": "Hyundai Kona Elektro",
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"cw": 0.29,
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"area": 2.37
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},
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{
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"car": "Hyundai Ioniq Elektro",
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"cw": 0.24,
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"area": 2.22
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}
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]
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# rho: [kg/m3]
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def rho(temperature_degc: float, p_pa: float =g_p0):
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return p_pa/(g_RS*(temperature_degc + 273.15))
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# Force : N = kg·m·s2
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def fd(rho: float, velocity_kmh: float, c_val: float, area: float):
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vel = velocity_kmh / 3.6
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cwa = c_val * area
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res = 0.5*rho*vel*vel*cwa
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return res
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# Fd vs. velocity, param: temperature
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temps_list = [-20, -10, 0, 10, 20, 30]
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vel_list = [20, 40, 60, 80, 100, 120, 130, 140, 160]
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reference = fd(rho(20), 100, c_val_id3, area_id3)
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temps_list_leg = [f"{t}°C" for t in temps_list]
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plot.figure()
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for temp_degc in temps_list:
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rho_t = rho(temp_degc)
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y_fd = []
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for vel_kmh in vel_list:
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fd_t = (fd(rho_t, vel_kmh, c_val_id3, area_id3)/reference - 1) * 100
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y_fd.append(fd_t)
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plot.plot(vel_list, y_fd)
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plot.title("Windwiderstand vs Geschwindigkeit")
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plot.ylabel("Windwiderstand [%]")
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plot.xlabel("Geschwindigkeit [km/h]")
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plot.legend(temps_list_leg)
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plot.grid()
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# Fd vs. velocity, param: car
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temp = 20
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vel_list = [20, 40, 60, 80, 100, 120, 130, 140, 160]
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car_list_leg = [f"{t['car']}" for t in car_list]
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rho_t = rho(temp)
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reference = fd(rho_t, 100, c_val_id3, area_id3)
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plot.figure()
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for car in car_list:
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y_fd = []
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for vel_kmh in vel_list:
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fd_t = (fd(rho_t, vel_kmh, car['cw'], car['area'])/reference - 1) * 100
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y_fd.append(fd_t)
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plot.plot(vel_list, y_fd)
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plot.ylabel("Windwiderstand ID.3 [%]")
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plot.xlabel("Geschwindigkeit [km/h]")
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plot.title("Windwiderstand vs Geschwindigkeit")
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plot.legend(car_list_leg)
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plot.grid()
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plot.figure()
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y_fd = []
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for vel_kmh in vel_list:
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fd_t = fd(rho_t, vel_kmh, c_val_id3, area_id3)
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y_fd.append(fd_t)
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plot.plot(vel_list, y_fd)
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plot.ylabel("Windwiderstand [N]")
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plot.xlabel("Geschwindigkeit [km/h]")
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plot.title("Windwiderstand vs Geschwindigkeit")
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plot.legend(car_list_leg)
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plot.grid()
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plot.show()
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