Honda CR-V SUV commercial vehicle develops 138kW at engine speed of 7000 rpm. It is fitted...

 

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Honda CR-V SUV commercial vehicle develops 138kW at engine speed of 7000 rpm. It is fitted with petrol engine which develops a maximum torque of 220 Nm at 4400 rpm. The vehicle gross weight is 15.7kN and curb weight is 12.4kN. The vehicle width is 1780 mm, wheel base is 2620 mm, height is 1770 mm, and ground clearance is 120 mm. The height of the centre of gravity (CG) is 650 mm above the ground and 1000 mm in front of the rear axle. The coefficient of rolling friction is 0.03; the aerodynamic drag coefficient is 0.25 and the coefficient of road adhesion is 0.8 a) What should be the braking proportions in the front and the rear wheels to get optimum braking effect? b) If the vehicle with above braking proportions travelling at 80kmph on a level road having road adhesion is 0.6 and rolling resistance is 0.015, is braked, which wheels will skid first? What is the maximum braking deceleration rate and braking efficiency achievable? Please justify your answers. Honda CR-V SUV commercial vehicle develops 138kW at engine speed of 7000 rpm. It is fitted with petrol engine which develops a maximum torque of 220 Nm at 4400 rpm. The vehicle gross weight is 15.7kN and curb weight is 12.4kN. The vehicle width is 1780 mm, wheel base is 2620 mm, height is 1770 mm, and ground clearance is 120 mm. The height of the centre of gravity (CG) is 650 mm above the ground and 1000 mm in front of the rear axle. The coefficient of rolling friction is 0.03; the aerodynamic drag coefficient is 0.25 and the coefficient of road adhesion is 0.8 a) What should be the braking proportions in the front and the rear wheels to get optimum braking effect? b) If the vehicle with above braking proportions travelling at 80kmph on a level road having road adhesion is 0.6 and rolling resistance is 0.015, is braked, which wheels will skid first? What is the maximum braking deceleration rate and braking efficiency achievable? Please justify your answers. Honda CR-V SUV commercial vehicle develops 138kW at engine speed of 7000 rpm. It is fitted with petrol engine which develops a maximum torque of 220 Nm at 4400 rpm. The vehicle gross weight is 15.7kN and curb weight is 12.4kN. The vehicle width is 1780 mm, wheel base is 2620 mm, height is 1770 mm, and ground clearance is 120 mm. The height of the centre of gravity (CG) is 650 mm above the ground and 1000 mm in front of the rear axle. The coefficient of rolling friction is 0.03; the aerodynamic drag coefficient is 0.25 and the coefficient of road adhesion is 0.8 a) What should be the braking proportions in the front and the rear wheels to get optimum braking effect? b) If the vehicle with above braking proportions travelling at 80kmph on a level road having road adhesion is 0.6 and rolling resistance is 0.015, is braked, which wheels will skid first? What is the maximum braking deceleration rate and braking efficiency achievable? Please justify your answers.