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ChronicQuantumAddict
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Please help with the following question, completely lost:
The behavior of a four stroke gasoline engine can be approximated by the so-called Otto cycle. The process is as follows (6 steps):
1) Isobaric Intake (from V=0) at atmospheric pressure up to volume V1 (maximal volume), Temperature T1
2) Adiabatic compression to volume V2, Temperature T2
3) Isochoric increase of Temperature during ignition to T3
4) Adiabatic expansion to V1 (max volume), Temperature T4
5) Isochoric decrease of temperature (to T1)
6) and Isobaric exhaust to V=0 at atmospheric pressure.
Sketch the process in a P-V diagram. Assume the working substance is an ideal gas and calculate the efficiency of the process. Express the result in terms of the temperatures T1, T2, T3, and T4. If the compression ratio is given by r = V1/V2, express the efficieny with r. For an Engine with r = 8, and gamma = 1.5 what do u obtain? (Note gamma is the ration of specific heats, Cp/Cv).
Please help, i don't know how a graph can be sketched on here, because i have an idea of the graph, but if someone could post this diagram along with a clue or the procedures on how to obtain the answer it would be much appreciated. Thanks
The behavior of a four stroke gasoline engine can be approximated by the so-called Otto cycle. The process is as follows (6 steps):
1) Isobaric Intake (from V=0) at atmospheric pressure up to volume V1 (maximal volume), Temperature T1
2) Adiabatic compression to volume V2, Temperature T2
3) Isochoric increase of Temperature during ignition to T3
4) Adiabatic expansion to V1 (max volume), Temperature T4
5) Isochoric decrease of temperature (to T1)
6) and Isobaric exhaust to V=0 at atmospheric pressure.
Sketch the process in a P-V diagram. Assume the working substance is an ideal gas and calculate the efficiency of the process. Express the result in terms of the temperatures T1, T2, T3, and T4. If the compression ratio is given by r = V1/V2, express the efficieny with r. For an Engine with r = 8, and gamma = 1.5 what do u obtain? (Note gamma is the ration of specific heats, Cp/Cv).
Please help, i don't know how a graph can be sketched on here, because i have an idea of the graph, but if someone could post this diagram along with a clue or the procedures on how to obtain the answer it would be much appreciated. Thanks