Subtopic: Thermodynamic principles of I.C. engines
Question Statement:
Which of the following idealizations are incorporated into the classical air-standard analysis of internal combustion engine power cycles?
Options:
(A) The working fluid is air behaving throughout as an ideal gas with constant specific heats.
(B) The combustion process is modeled as an external heat addition from a high-temperature reservoir.
(C) The exhaust blowdown and scavenging processes are replaced by a constant-volume heat rejection to an external cold sink.
(D) Compression and expansion strokes are assumed to be internally reversible and adiabatic (isentropic).
Answer Key:
A, B, C, D
Step-by-Step Solution & Explanation
All four assumptions define the ideal air-standard cycle:
• Fixed composition ideal gas with constant $c_p$ and $c_v$.
• Closed cycle where external heat transfers replace combustion and gas exchange.
• Isentropic (reversible adiabatic) compression and expansion processes.