Open vs. Closed Cycle Gas Turbines – Identify the Wrong Statement Select the incorrect statement regarding open- and closed-cycle gas turbine plants.

Introduction / Context:
Gas turbine plants are implemented as open (Brayton with atmospheric intake and exhaust) or closed cycles (recirculated working fluid through external heat addition and rejection). Distinguishing their characteristics is vital for plant design and performance analysis.

Given Data / Assumptions:

• Open cycle exchanges mass with atmosphere; closed cycle does not.
• Closed cycle uses external heat exchangers (heater, cooler, regenerator).
• Pressures in a closed cycle are set by plant design, not by ambient pressure.

Concept / Approach:

The incorrect statement is the one tying closed-cycle pressure range to atmospheric pressure. In closed cycles, absolute pressure levels and ratios are chosen independently (within mechanical limits) since the working fluid is contained. In contrast, open cycles usually have compressor inlet near atmospheric pressure, so their absolute levels depend on ambient conditions.

Step-by-Step Solution:

Verification / Alternative check:

Textbook schematics show a closed Brayton loop pressurized to several bars for compactness and efficiency, independent of ambient pressure.

Why Other Options Are Wrong:

Options (a), (d), and (e) reflect standard definitions; (c) is a qualitative statement about external surfaces and does not claim false dependencies.

Common Pitfalls:

Assuming all gas turbines must inhale/exhaust to atmosphere; forgetting that pressurizing a closed loop improves heat-exchanger effectiveness and specific power.

Final Answer:

In the closed cycle gas turbine, the pressure range depends upon the atmospheric pressure.