The analysis is as follows:
Wind resistance coefficient (Cd) = frontal wind resistance (F) 2 (air density () x frontal projected area of the front of the car (A) x square of the vehicle speed (V2), this is the formula for calculating the wind resistance of a car
Calculated according to this method, if a car moves forward at a speed of. At 80 km/h, 60% of the fuel consumption is used to overcome wind resistance. If the speed reaches more than 200 kilometers per hour, the air resistance accounts for almost 85. % of all driving resistance. For every 10% decrease in wind resistance coefficient, the fuel consumption of ordinary fuel vehicles will decrease by 3% and the range of new energy vehicles will increase by 10 km. shows the importance of the energy consumption saving coefficient the noise level and driving performance in the car, affects.thus improving driving comfort.
Wind and air resistance are not exactly the same. Wind is caused by airflow, which is essentially air. reduce resistance when going downwind, and it can increase resistance when going against the wind. As you said, when you turn on the electric fan, there is actually no resistance, because you have no movement or tendency for movement. the wind force at that time is just pure wind force. If the air is stationary, there is only air resistance when moving, and there is no wind force if the air is flowing, i.e. the wind is generated and the direction of the wind; is consistent with the direction of movement. When the wind shifts (tailwind), resistance can be reduced; when the wind direction is opposite to the direction of movement (headwind), the resistance will be increased. time = air resistance when there isno wind + wind force (think about it, the air is originally good. If it doesn't move, there will be resistance when you crush, but it is not big and the feeling is not is not obvious. In the end, he confronts you and runs towards you. Now it's really difficult to walk)