Tag Archive for: sulting

Compressing gases requires work and the re- sulting energy is usually converted to heat; if this heat does not escape, the gas’s temper- ature will…

Compressing gases requires work and the re-sulting energy is usually converted to heat; ifthis heat does not escape, the gas’s temper-ature will rise. This effect is used in dieselengines: The compressed air gets so hot thatwhen the fuel is injected, it ignites withoutany spark plugs.As an example, consider a cylinder in adiesel engine in which air is compressed toone twentieth of its original volume while thepressure rises from 1 atm to 47 atm (absolute,not gauge). Note that because the air heatsup while being compressed, its pressure risesmore than twenty-fold.If the air is taken into the cylinder at 35◦C,how hot does it get after being compressed?Answer in units of ◦C.