- refactored luftwiderstand

luftwiderstand.py

@@ -9,46 +9,16 @@ g_p0 = 101325
 g_RS = 287.54
 
 # CW-Wert und Stirnfläche
-c_val_id3 = 0.267
-area_id3 = 2.360	# m^2
 
-car_list = [
-	{
-		"car": "VW id.3",
-		"cw": 0.267,
-		"area": 2.360
-	},
-	{
-		"car": "Tesla Model Y LR AWD",
-		"cw": 0.23,
-		"area": 2.518
-	},
-	{
-		"car": "Tesla Model 3 LR AWD",
-		"cw": 0.23,
-		"area": 2.220
-	},
-	{
-		"car": "Polestar 2",
-		"cw": 0.278,
-		"area": 2.480
-	},
-	{
-		"car": "Renault Zoe",
-		"cw": 0.33,
-		"area": 2.27
-	},
-	{
-		"car": "Hyundai Kona Elektro",
-		"cw": 0.29,
-		"area": 2.37
-	},
-	{
-		"car": "Hyundai Ioniq Elektro",
-		"cw": 0.24,
-		"area": 2.22
-	}
-]
+car_list = {
+	'VW id.3' : {'cw': 0.267, 'area': 2.36},
+	'Tesla Model Y LR AWD': {'cw': 0.23, 'area': 2.518},
+	'Tesla Model 3 LR AWD': {'cw': 0.23, 'area': 2.220},
+	'Polestar 2': {'cw': 0.278, 'area': 2.480},
+	'Renault Zoe': {'cw': 0.33, 'area': 2.27},
+	'Hyundai Kona Elektro': {'cw': 0.29, 'area': 2.37},
+	'Hyundai Ioniq': {'cw': 0.24, 'area': 2.22}
+}
 
 temp_list = [-20, -10, 0, 10, 20, 30]
 vel_list = [20, 40, 60, 80, 100, 120, 130, 140, 160]
@@ -65,32 +35,34 @@ def fd(rho: float, velocity_kmh: float, c_val: float, area: float):
 	res = 0.5*rho*vel*vel*cwa
 	return res
 
-def plot_1(fd_reference):
+def plot_1(car_ref, t_ref=20, v_ref=100):
+	fd_reference_100 = fd(rho(t_ref), v_ref, car_ref['cw'], car_ref['area'])
 	temps_list_leg = [f"{t}°C" for t in temp_list]
 	plot.figure()
 	for temp_degc in temp_list:
 		rho_t = rho(temp_degc)
 		y_fd = []
 		for vel_kmh in vel_list:
-			fd_t = (fd(rho_t, vel_kmh, c_val_id3, area_id3)/fd_reference - 1) * 100
+			fd_t = (fd(rho_t, vel_kmh, car_ref['cw'], car_ref['area'])/fd_reference_100 - 1) * 100
 			y_fd.append(fd_t)
 
 		plot.plot(vel_list, y_fd)
 
-	plot.title("Luftwiderstand vs Geschwindigkeit")
+	plot.title(f"Luftwiderstand vs Geschwindigkeit, T={t_ref}°C, v={v_ref}km/h")
 	plot.ylabel("Luftwiderstand [%]")
 	plot.xlabel("Geschwindigkeit [km/h]")
 	plot.legend(temps_list_leg)
 	plot.grid()
 
-def plot_2(temp=20):
+def plot_2(car_ref, t_ref=20, v_ref=100):
 	''' Fd vs. velocity, param: car '''
 	# [kmh]
-	car_list_leg = [f"{t['car']}" for t in car_list]
-	rho_t = rho(temp)
-	reference = fd(rho_t, 100, c_val_id3, area_id3)
+	car_list_leg = [f"{t}" for t in car_list.keys()]
+	rho_t = rho(t_ref)
+	reference = fd(rho_t, v_ref, car_ref['cw'], car_ref['area'])
 	plot.figure()
-	for car in car_list:
+	for key in car_list:
+		car = car_list[key]
 		y_fd = []
 		for vel_kmh in vel_list:
 			fd_t = (fd(rho_t, vel_kmh, car['cw'], car['area'])/reference - 1) * 100
@@ -100,17 +72,17 @@ def plot_2(temp=20):
 
 	plot.ylabel("Luftwiderstand ID.3 [%]")
 	plot.xlabel("Geschwindigkeit [km/h]")
-	plot.title(f"Luftwiderstand vs Geschwindigkeit, Temperature {temp}°C")
+	plot.title(f"Luftwiderstand vs Geschwindigkeit, T={t_ref}°C, v={v_ref}km/h")
 	plot.legend(car_list_leg)
 	plot.grid()
 
-def plot_3(y_fd, y_pwr, temp=20):
-	car_list_leg = [f"{t['car']}" for t in car_list]
+def plot_3(y_fd, y_pwr, t_ref=20):
+	car_list_leg = [f"{t}" for t in car_list.keys()]
 	fig, ax1 = plot.subplots()
 	ax1.plot(vel_list, y_fd)
 	ax1.set_ylabel("Luftwiderstand [N]")
 	ax1.set_xlabel("Geschwindigkeit [km/h]")
-	ax1.set_title(f"Luftwiderstand vs Geschwindigkeit, Temperature {temp}°C")
+	ax1.set_title(f"Luftwiderstand vs Geschwindigkeit, T={t_ref}°C")
 	ax1.legend(car_list_leg)
 	ax2 = ax1.twinx()
 	ax2.set_ylabel("Antriebsleistung [kW]", color='tab:red')
@@ -119,7 +91,7 @@ def plot_3(y_fd, y_pwr, temp=20):
 	ax1.grid()
 
 def plot_4(y_fd, y_energy, temp=20):
-	car_list_leg = [f"{t['car']}" for t in car_list]
+	car_list_leg = [f"{t}" for t in car_list.keys()]
 	fig, ax1 = plot.subplots()
 	ax1.plot(vel_list, y_fd)
 	ax1.set_ylabel("Luftwiderstand [N]")
@@ -134,21 +106,21 @@ def plot_4(y_fd, y_energy, temp=20):
 	plot.show()
 
 def main() -> None:
+	car = car_list['VW id.3']
 	# Fd vs. velocity, param: temperature
-	reference = fd(rho(20), 100, c_val_id3, area_id3)
 	temp_ref = 20
 
 	# Luftwiderstand [%] vs. Geschwindigkeit [kmh], Param: Temperatur
-	plot_1(reference)
+	plot_1(car)
 
 	# Luftwiderstand [%] vs. Geschwindigkeit [kmh] at 20°C, Param: Car Model
-	plot_2(temp_ref)
+	plot_2(car, temp_ref)
 
 	y_fd = []
 	y_pwr = []
 	y_energy = []
 	for vel_kmh in vel_list:
-		fd_t = fd(rho(temp_ref), vel_kmh, c_val_id3, area_id3)
+		fd_t = fd(rho(temp_ref), vel_kmh, car['cw'], car['area'])
 		y_fd.append(fd_t)
 		y_pwr.append(fd_t*vel_kmh/1000/3.6)
 		y_energy.append(fd_t*vel_kmh/1000/3.6*100/vel_kmh)