Simple Brayton (gas turbine) cycle: typical performance How are the thermal efficiency and the work ratio of a simple (un-regenerated, un-intercooled, un-reheated) gas turbine cycle generally characterized? Choose the best descri…

Concept/Approach In a simple Brayton cycle, a large fraction of turbine work is consumed by the compressor, yielding a low work ratio (Wnet/WT). Without regeneration/reheat/intercooling, the thermal efficiency is also modest. Typical trend Increasin…

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Simple Brayton (gas turbine) cycle: typical performance How are the <em>thermal efficiency</em> and the <em>work ratio</em> of a simple (un-regenerated, un-intercooled, un-reheated) gas turbine cycle generally characterized? Choose the best description.

Difficulty: Easy

Low
Very low
High
Very high

Correct Answer: Low

Explanation:

Concept/Approach

In a simple Brayton cycle, a large fraction of turbine work is consumed by the compressor, yielding a low work ratio (W_net/W_T).
Without regeneration/reheat/intercooling, the thermal efficiency is also modest.

Typical trend
Increasing pressure ratio raises efficiency up to an optimum, but simple cycles still remain “low” compared with improved cycles.

Final Answer
Low

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