a) A passenger car is driving up an incline of 3 degrees at a constant speed...

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a) A passenger car is driving up an incline of 3 degrees at a constant speed of 40 km/h. The vehicle is powered by a 1.5 litre, 4-stroke, SI engine with engine operating range from 1000 (rpm) to 6000 (rpm). The vehicle parameters are as follows: Final Drive ratio = 3.0: 1 efficiency 95% Gear ratios all with efficiency 93% o 1st = 3.60: 1 o 2nd = 2.30:1 o 3rd=1.30:1 4th = 1.00:1 o o 5th = 0.75:1 Tyre Rolling Radius = 0.33 (m) Fully loaded mass = 1500 (kg) Rolling resistance coefficient = 0.017 (-) Cd = 0.27 (-) Frontal Area = 1.9 (m) Fuel density = 0.75 (kg/l) Assume air with a density of p = 1.225 (kg/m). Figure Q2-1 illustrates the BSFC map of the engine of the car. bsfc (g/kWh) BMEP (bar) 12 10 8 2 0 1000 240 2000 193 3000 RPM 260 4000 280 300 Figure Q2-1 BSFC map of engine 340 5000 6000 Answer the following questions: i) Calculate the engine operating point (engine speed and torque) assuming the driver has selected the most efficient gear. [6 marks] ii) Calculate the fuel consumption at this operating condition in litres per 100 km. [3 marks] Question continued on next a) A passenger car is driving up an incline of 3 degrees at a constant speed of 40 km/h. The vehicle is powered by a 1.5 litre, 4-stroke, SI engine with engine operating range from 1000 (rpm) to 6000 (rpm). The vehicle parameters are as follows: Final Drive ratio = 3.0: 1 efficiency 95% Gear ratios all with efficiency 93% o 1st = 3.60: 1 o 2nd = 2.30:1 o 3rd=1.30:1 4th = 1.00:1 o o 5th = 0.75:1 Tyre Rolling Radius = 0.33 (m) Fully loaded mass = 1500 (kg) Rolling resistance coefficient = 0.017 (-) Cd = 0.27 (-) Frontal Area = 1.9 (m) Fuel density = 0.75 (kg/l) Assume air with a density of p = 1.225 (kg/m). Figure Q2-1 illustrates the BSFC map of the engine of the car. bsfc (g/kWh) BMEP (bar) 12 10 8 2 0 1000 240 2000 193 3000 RPM 260 4000 280 300 Figure Q2-1 BSFC map of engine 340 5000 6000 Answer the following questions: i) Calculate the engine operating point (engine speed and torque) assuming the driver has selected the most efficient gear. [6 marks] ii) Calculate the fuel consumption at this operating condition in litres per 100 km. [3 marks] Question continued on next

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