What does driving resistance mean?
1 Answers
Driving resistance refers to the resistance encountered by a vehicle during movement. The driving resistance of a vehicle consists of four components: rolling resistance, acceleration resistance, gradient resistance, and air resistance. Below is more detailed information about these resistances: 1. Pressure resistance: This is the component of the resultant force of normal forces acting on the outer surface of the vehicle in the direction of travel, accounting for approximately 55% to 65% of air resistance. When a vehicle moves forward through the air medium, the air at the front of the vehicle is compressed, increasing the pressure acting on the front, while a vortex zone forms at the rear, creating negative pressure and reducing the pressure acting on the rear. 2. Induced resistance: This effect causes the air flow speed to be faster at the top and slower at the bottom of the vehicle during high-speed driving, resulting in different air pressures between the upper and lower parts. The greater pressure at the bottom creates a horizontal component force difference, known as induced resistance, which accounts for about 6%-8% of air resistance. This force essentially acts as a lifting force on the vehicle, which is the main reason some cars feel 'floaty' at high speeds. 3. Interference resistance: This is the air resistance caused by protruding elements on the vehicle's surface during movement, such as door handles, rearview mirrors, suspension guide rods, axles, fenders, etc., accounting for about 12%-18% of the total air resistance of the vehicle.
