Jinan Benz car maintenance: as the weather gets warmer and warmer, many friends must use the weekend to drive around. If the distance is relatively long, you can't avoid running on the high-speed. Now some car owners should have questions: when running on the high-speed, does it cost oil to turn on the air conditioner or to turn on the windows?

开冷风为什么费油？

Why does it cost oil to turn on the cold air?

汽车空调的制冷系统虽然跟家用空调在结构上有差异，但它们有一点是一样的，都是通过压缩机把气态制冷剂进行压缩，然后释放出热量。

Although the refrigeration system of automobile air conditioner is different from that of household air conditioner in structure, they have one thing in common. They compress the gaseous refrigerant through the compressor and release heat.

汽车的空调压缩机需要靠发动机提供能量进行工作，这就等于无形中增加了发动机的负荷，这就是夏天开冷风费油的主要原因。

The air-conditioning compressor of the car needs to work with the energy provided by the engine, which is tantamount to an invisible increase in the load of the engine, which is the main reason for the fuel consumption of cold air in summer.

特别是低转速状态下，发动机在保证不熄火的情况下还要给空调压缩机分配一定的动力，所以当A/C按键点亮时，汽车的怠速会比不开空调高一点。

Especially in the low speed state, the engine will distribute certain power to the air conditioning compressor under the condition of ensuring that the engine does not shut down. Therefore, when the A / C button is on, the idle speed of the car will be a little higher than that without the air conditioning.

有个观点必须清楚，就算汽车再，高速行驶的时候也不可能一点风阻都没有。当然像法拉利、兰博基尼这样的超跑，会死抠车身空气动力学，目的也是降低风阻系数。

First of all, it must be clear that even if the car is more advanced, it is impossible to have no wind resistance when driving at high speed. Of course, super running like Ferrari and Lamborghini will focus on the aerodynamics of the body, and the purpose is to reduce the drag coefficient.

当我们开车在高速上面行驶的时候，如果四个车窗处于关闭状态，车身将会形成一个相对完整的外形，风阻系数是比较小的。假如打开车窗，外形被破坏了，流经车体表面的高速气流会从车窗吹进来，风阻系数将会大大提高。由于发动机需要更大的输出功率对抗风阻，所以油耗也会明显提高。

When we drive at a high speed, if the four windows are closed, the body will form a relatively complete shape, and the wind resistance coefficient is relatively small. If you open the window, the shape will be damaged, and the high-speed air flow flowing through the surface of the car body will blow in from the window, and the wind resistance coefficient will be greatly improved. Since the engine needs more output power to resist wind resistance, the fuel consumption will also be significantly improved.

数据显示，当汽车开到80~100km/h时，开空调和开窗户增加的风阻系数所消耗的汽油相差无几；如果速度再快一些，比如120km/h的时候，开窗户确实比开空调更费油。

The data show that when the car is driven to 80 ~ 100km / h, the gasoline consumed by the increased drag coefficient of opening the air conditioner and opening the window is almost the same; If the speed is faster, for example, at 120km / h, opening the window really costs more fuel than opening the air conditioner.

高速正确的开窗方法

High speed and correct window opening method

就像现在，天气虽然暖和了，但也没到开空调的地步，高速行车的时候想透透气怎么办？建议可以打开空调外循环。

Just like now, although the weather is warm, it is not enough to turn on the air conditioner. What should I do if I want to breathe when driving at high speed? It is recommended to turn on the external circulation of the air conditioner.

如果非要开窗通风的话，可以只开前排一侧的窗户，这种情况下气流在车内会相对均衡。也可以开两扇窗户，但还要注意不能是同侧的，要对角线开，这样能获得更好的空气对流效果，是这种方法产生的风噪比较低。

If you have to open windows for ventilation, you can only open the windows on the front side. In this case, the air flow will be relatively balanced in the car. Two windows can also be opened, but it should be noted that they should not be on the same side, but should be opened diagonally, so as to obtain better air convection effect. The key point is that the wind noise ratio produced by this method is low.

如今，很多人买车都会关注车型的综合油耗，毕竟这油价眼看就要飞上天了。其实，影响汽车油耗的因素有很多，除了开冷风、高速开窗户，还跟日常的开车习惯有很大的关系。

Nowadays, many people will focus on the comprehensive fuel consumption of models when buying cars. After all, the oil price is about to soar. In fact, there are many factors that affect car fuel consumption. In addition to opening cold air and opening windows at high speed, it is also closely related to daily driving habits.

有些人习惯性的把家用车当赛车用，经常是油门刹车天上一脚，地上一脚的踩，这种一走一停的激烈驾驶特别费油，要不然那些油电混动的车也不会在起步的时候采用电驱。

Some people habitually use household cars as racing cars. They often step on the accelerator and brake. This fierce driving of walking and stopping is particularly fuel consuming. Otherwise, those hybrid cars will not use electric drive when starting.