【小实验】5mph的速度区别对于油耗的大影响

CiTY_HuNTeR

turbopascal 发表于 2013-12-21 18:12
>从我平时开的80mph减到75mph，就能把mpg提升近3个点，令人惊讶

考虑到速度慢了后要花更多时间开到目的地 ...

its mile per gallon

Let's say we ran 80 miles. It will take you 1 hour to get there. If you ran at 75, it takes you 1+5/75 hours, ie. the difference is 4 minutes every hour. Elementary school level math, right? Normally people need to go or vehicle need to fuel up every 2-3 hours. So, what 8 minutes can buy you? Maybe first in the toilet waiting lane?

And what you are risking for? 3 or more mpg (only talking about f150), less risk of being caught by a radar, much less stress (depending on road condition, some interstates in Texas can safely go as fast as 90 mph plus.

And I'm just taking about trucks here. Please do not bring other type of vehicles in.

Of course if you are in a hurry, say embulance driver, is a different story

turbopascal

CiTY_HuNTeR 发表于 2013-12-22 03:48
its mile per gallon

Lest say we ran 80 miles. It will take you 1 hour to get there. If you ran at  ...

啊，是我自己糊涂了，看到的是多少英里，脑子里想的是单位时间耗油。所以我的上一个帖子没有意义。

CiTY_HuNTeR

turbopascal 发表于 2013-12-22 15:38
啊，是我自己糊涂了，看到的是多少英里，脑子里想的是单位时间耗油。所以我的上一个帖子没有意义。 ...

Never mind bro, I was an idiot driving 90+ mph on long distance. Been there, done that.

Yes, I saved about 30-40 minutes on our 12 hours travel to NYC, but it was all wasted by a small bladder kid who needed to go every single hour. And I got bad mpgs, I'm exhausted, and higher risk on getting ticket.

So I felt it really doesn't worth to rush it. (Although I still run 80mph on my way to work, 5 minutes more precious sleeping... But not faster than that, because the mpg will get really ugly)

pandamalone

车行驶阻力两个来源，滚动阻力和风阻。后者跟车速平方关系，消耗功率跟车速是立方关系

而前者我看到的说法，滚动阻力在超过一个上限前（跟traction或者说滑移率相关）基本不变，只跟轮胎和车自重等肥速度因素相关，也就是说对功率的贡献仅是线性关系

所以车速上来当风阻成为主要贡献后，车速对油耗的影响就会非常明显

实际上如果试一下45mph巡航，经济性还会更好，不过就是不现实了