For gasoline engines, a larger compression ratio, defined as Vmax / Vmin for the piston, means a greater efficiency. In a typical engine, air is mixed with fuel at atmospheric pressure (1x105 Pa) and 0.5 L of this mixture is drawn into a piston, compressed to Vmin, and then ignited. However, a piston can only compress the mixture so much before the fuel can be ignited by the increase in temperature of the air alone, usually at a temperature of 250oC. If we consider the compression to be very rapid, we can say PVγ is a constant, where γ = 1.24 for a fuel-air mixture. If the fuel-air mixture is drawn into the piston at 27oC, what would the maximum theoretical compression ratio be for this engine?
Frequently Asked Questions
What scientific concept do you need to know in order to solve this problem?
Our tutors have indicated that to solve this problem you will need to apply the !! Adiabatic Processes concept. If you need more !! Adiabatic Processes practice, you can also practice !! Adiabatic Processes practice problems.
How long does this problem take to solve?
Our expert Physics tutor, Juan took 9 minutes and 43 seconds to solve this problem. You can follow their steps in the video explanation above.