?Many friends have raised questions about the wind resistance coefficient and aerodynamic design. Everyone seems interested in this knowledge. So what is the drag coefficient? Why is the coefficient of drag so important for electric vehicles? Everyone knows the concept of drag coefficient, and it is frequently "on display" in the automotive industry. But in reality, it is very important not only in the automotive industry, but also in many other areas. Today, let's get acquainted again and see why it is so popular.
Drag coefficient is a common name, the correct name is air resistance coefficient. Taking the automobile industry as an example, vehicles will experience air force while driving, which we call aerodynamic force. The aerodynamic force can be divided into three components, namely the drag force D, the forcethis of lift L and the lateral force s. More generally, when a car moves forward, the air blocks it and always drives it forward (air drag depending on the shape, it can also lift (air lift) it can also push the vehicle laterally ( lateral air); force) ).
Mercedes EQ number one:eqs-0.20cd is a large luxury pure electric car produced by Mercedes EQ. Developed based on the EVA (Large Electric Vehicle Framework) platform, the EQS features incredibly elegant styling and the élan of a large luxury car. The slender body of the “single arc design” perfectly combines aerodynamic design with a wind resistance coefficient of only 0.20 Cd, setting a new record for mass-produced cars in the world. In addition, the three-screen design integrated into the car and the mbux super screen with a total width of more than 141 cm elevate the technological atmosphere of the cabin to new heights.unprecedented. Mercedes-Benz is also amazing with electric vehicles. The dual-motor four-wheel drive version of the EQS has a maximum power of 385 kW and a maximum torque of 855 n. The range under M.wltp conditions is 770 km and the range under CLTC conditions is more than 800 km.
In terms of autonomous driving, the currently launched EQS integrates sensing hardware such as lidar, millimeter wave radar and ultrasonic sensors, and is equipped with high-precision maps. In the near future, it will be upgraded to almost L3 level advanced driving assistance via OTA, which can realize automatic driving assistance functions on highways and congested city roads. The vehicle can automatically change lanes, overtake and avoid obstacles, and Tesla Le. The FSD pulled is pretty good. Tesla, second in the ranking: Model S Play-0.208 CDS Model Play is the high-end model ofe the new Model S from Tesla. The new car is equipped with a completely new battery and has a range of 628 kilometers. At the same time, the car also broke the acceleration record for a production car, with its 0-60 mph acceleration time compressed to 2 seconds.
Zhiji Auto No. 3: l7-0.210cd, Zhiji is a high-end electric vehicle company led by SAIC. At the Shanghai Auto Show, pre-sales of the first L7 model officially began. The pre-sale price of “Angel Wheel” is 408,800 yuan. The new car is quite comparable to the standard Willai et7 in terms of positioning, configuration and performance.
Recently, the wisdom L7 completed the wind tunnel certification test at the Chongqing Wind Tunnel Center of China Automotive Research Institute. The results show that the drag coefficient of the L7 straight machine is 0.21, which ranks it among themost mass-produced res in the world. In terms of power, Zhiji L7 is equipped with a high-performance dual-motor full drive system with high-speed response. The power output reaches 400 kW/700 nm, and the acceleration time to 100 kilometers is only 3.9 seconds. The power battery was jointly developed by Zhiji and Ningde Times. It adopts “silicon-doped lithium replenishment” technology and has the characteristics of zero attenuation over 200,000 kilometers and spontaneous combustion. The vehicle is equipped as standard with a 93 kWh battery, which can last up to 615 km under NEDC conditions. At the same time, the 115 kWh battery can be upgraded, and the official indicator gives a maximum range of more than 1,000 kilometers.
There is wind resistance when electric vehicles move forward. The faster the speed, the greater the wind resistance.veed if wind resistance is used to drive a wind turbine
< p>Is the lower the wind resistance coefficient of the car, the lower the fuel consumption?
The drag coefficient is both familiar and unfamiliar to many people. In the opinion of ordinary car owners, car manufacturers are trying to reduce the drag coefficient, which means they can have a better car. . Fuel economy. Does this mean the lower the wind resistance the better? Looking at the automobile market, many streamlined cars have good fuel consumption performance. On the other hand, fuel-intensive, square-shaped cars such as trucks, vans, and buses have no drag coefficient. The lower the drag coefficient, the better the fuel consumption. Good point. TodayToday let me explain to my friends what drag coefficient is.
What is drag coefficient?
We opened Encyclopedia XX, which clearly explains the definition of drag coefficient, but it seems a bit obscure. Let me summarize it in a simple and easy to understand way: Drag coefficient is a mathematical parameter obtained. Through scientific experiments, the wind resistance coefficient can be used to calculate the amount of air resistance the car receives when driving. The higher the wind resistance coefficient, the greater the air resistance the car receives. This may also explain why cars with a high drag coefficient have high fuel consumption.
How is the drag coefficient measured?
We said above that the drag coefficient is measured by scientific experiments, and theWind tunnel experiments constitute a very important part of this. A wind tunnel is a device used to measure wind resistance. As shown in the image below, a giant fan is placed in a tunnel and the car drives through the tunnel. The fan wind is used to simulate the real conditions encountered by the tunnel. car when you are driving.
This is not as simple an experiment as it seems, and the equipment is expensive, and the cost of using the wind tunnel laboratory is also quite high. Therefore, before the experiment, engineers will conduct simulated wind resistance experiments on computers through simulation software to reduce the actual cost of wind tunnel testing. But even so, any car still needs hundreds of hours of testing before being mass-produced. Since testing the drag coefficient is so expensive, automakers who want to rreducing their costs still won't save on this. This shows the importance of reducing the drag coefficient to improve product strength.
In an era of soaring oil prices, consumers often prefer to buy a vehicle with low horsepower rather than high fuel economy. High fuel economy is so bad that it's really worth better buy an electric car that doesn't hold its value very well. Automakers who want to continue to shine in the field of fuel vehicles really can't save this kind of expense. .
Is the smaller the drag coefficient the better?
The answer is no. If the wind resistance coefficient of the car is very low, the lift generated when driving will also increase, resulting in what we commonly call high-speed flutter. Family cars cannot be drivenr too fast and the max speed of 120 may not make you feel too deeply. But it's especially evident when it comes to racing cars. The car itself has undergone a lot of lightweighting, and its weight is already low. If there is not enough downforce on the track, the car can fly into a corner. Many racing cars feature a large, wide rear wing at the rear of the car.
However, even if it seems cool to install a large rear spoiler on a civilian car, the rear spoiler installed by yourself will probably not have any aerodynamic effect, and will also increase the drag resistance. wind and will increase fuel consumption. besides being cool it's useless.
This is indeed completely false. If you have studied relevant specializations, you will know where you are going wrong. If you haven't learned it, it will be difficult to explain it to you. But one thing you simply must rThe bottom line is that no matter how you upgrade it, the electricity generated by the extra resistance of the car pushing the generator fan will never be greater than the extra electricity consumed. This is the law of conservation of energy. Even if you are a scientist, you cannot solve this problem.