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?

開冷風為什么費油？

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

汽車空調的制冷系統雖然跟家用空調在結構上有差異，但它們有一點是一樣的，都是通過壓縮機把氣態制冷劑進行壓縮，然后釋放出熱量。

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.

汽車的空調壓縮機需要靠發動機提供能量進行工作，這就等于無形中增加了發動機的負荷，這就是夏天開冷風費油的主要原因。

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.

特別是低轉速狀態下，發動機在保證不熄火的情況下還要給空調壓縮機分配一定的動力，所以當A/C按鍵點亮時，汽車的怠速會比不開空調高一點。

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.

首先有個觀點必須清楚，就算汽車再高級，高速行駛的時候也不可能一點風阻都沒有。當然像法拉利、蘭博基尼這樣的超跑，會死摳車身空氣動力學，目的也是降低風阻系數。

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.

當我們開車在高速上面行駛的時候，如果四個車窗處于關閉狀態，車身將會形成一個相對完整的外形，風阻系數是比較小的。假如打開車窗，外形被破壞了，流經車體表面的高速氣流會從車窗吹進來，風阻系數將會大大提高。由于發動機需要更大的輸出功率對抗風阻，所以油耗也會明顯提高。

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.

數據顯示，當汽車開到80~100km/h時，開空調和開窗戶增加的風阻系數所消耗的汽油相差無幾；如果速度再快一些，比如120km/h的時候，開窗戶確實比開空調更費油。

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.

高速正確的開窗方法

High speed and correct window opening method

就像現在，天氣雖然暖和了，但也沒到開空調的地步，高速行車的時候想透透氣怎么辦？建議可以打開空調外循環。

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.

如果非要開窗通風的話，可以只開前排一側的窗戶，這種情況下氣流在車內會相對均衡。也可以開兩扇窗戶，但還要注意不能是同側的，要對角線開，這樣能獲得更好的空氣對流效果，是這種方法產生的風噪比較低。

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，很多人買車都會關注車型的綜合油耗，畢竟這油價眼看就要飛上天了。其實，影響汽車油耗的因素有很多，除了開冷風、高速開窗戶，還跟日常的開車習慣有很大的關系。

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.

有些人習慣性的把家用車當賽車用，經常是油門剎車天上一腳，地上一腳的踩，這種一走一停的激烈駕駛特別費油，要不然那些油電混動的車也不會在起步的時候采用電驅。

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.