Timeline for What affects an internal-combustion engine's efficiency?
Current License: CC BY-SA 3.0
4 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Apr 6, 2018 at 18:53 | comment | added | JanKanis | Too cold (when the engine has only been running a short time) is mainly bad because the burning fuel mixture is cooled down near the cylinder walls and then doesn't burn as completely. Also the hot combustion gases cool faster while pushing the piston down, this decreases the pressure and thus the extracted power. | |
| Apr 6, 2018 at 18:48 | comment | added | JanKanis | Overheating is bad, but the temperatures that melt steel are much higher than what engines reach. What happens first is the steel starting to deform plastically very slowly. | |
| Apr 6, 2018 at 18:33 | comment | added | JanKanis | To comment on your educated guesses: I'm not sure about air density improving efficiency. First of all higher air density allows more air and fuel in a single stroke, increasing the power output but also the fuel usage. Stuff like ambient temperature and higher compression ratios affect engine design, but nearly all car engines have a fixed compression ratio, and I'm not sure how adaptive cooling is in current engines, so for a given engine those probably don't matter much. | |
| Jul 3, 2015 at 22:05 | history | answered | feetwet | CC BY-SA 3.0 |