Cycle Recognition – Two Isothermal and Two Constant-Pressure Processes A thermodynamic cycle that comprises two isothermal processes (heat addition and heat rejection) and two constant-pressure regenerative processes is known as the Ericsson cycle. Evaluate the statement.

Introduction / Context:
Identifying classic ideal cycles from their process makeup helps in selecting appropriate analysis methods and understanding performance limits. The Ericsson cycle is frequently compared with Carnot, Stirling, and Joule (Brayton) cycles, so clarity about its component processes is essential.

Given Data / Assumptions:

• Ideal, fully reversible processes with perfect regeneration.
• Working fluid approximated as an ideal gas with constant properties.
• Heat addition/removal executed isothermally; internal heat exchange executed at constant pressure.

Concept / Approach:

The Ericsson cycle consists of two isothermal legs (compression at the lower temperature and expansion at the higher temperature) and two isobaric regenerative legs. The isobaric legs transfer heat internally between the hot and cold streams in a regenerator, enabling the cycle to approach Carnot efficiency under ideal conditions. By contrast, the Stirling cycle uses isothermal legs plus two constant-volume (isochoric) regenerative legs, and the Joule (Brayton) cycle uses two isentropic legs with two constant-pressure heat-transfer legs to external reservoirs (not regenerative by definition).

Step-by-Step Solution:

Verification / Alternative check:

Graphically, T–s shows two horizontal isotherms linked by near-horizontal isobars (with regeneration), whereas Stirling would show vertical isochores for the regenerative legs. Textbook definitions align with this process identification.

Why Other Options Are Wrong:

Calling it Stirling confuses isobaric with isochoric regeneration. Restricting to 'open cycles' is unnecessary. While perfect regeneration is an idealization, the cycle definition itself is indeed two isothermal plus two isobaric processes.

Common Pitfalls:

Mixing Ericsson and Brayton; assuming any constant-pressure legs imply Brayton rather than recognizing the isothermal legs that define Ericsson.

Final Answer:

True