In an open-cycle gas turbine featuring an exhaust heat exchanger, the atmospheric air prior to compressor entry is____________________?
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Answer: B. compressed air before entering the combustion chamber is heated
Explanation
In an open cycle gas turbine featuring a heat exchanger, compressed air is preheated. Exhaust gases transfer thermal energy to the compressed air before it enters the combustion chamber. Preheating the air reduces the fuel required to reach turbine operating temperatures efficiently. Gas turbines operate on the Brayton thermodynamic cycle involving compression, combustion, and expansion. Regeneration utilizes waste exhaust heat to improve overall thermal efficiency in gas turbine engines. Heat exchangers or recuperators capture high temperature exhaust gas energy before atmospheric release.
Power generation plants use exhaust heat exchangers to maximize fuel economy in industrial gas turbines. Improving cycle efficiency reduces operating costs and lowers greenhouse gas emissions in power plants. Thermodynamic optimization of gas turbines plays a vital role in modern energy conversion engineering. Option A is vague and fails to specify that compressed air is the exact medium being heated. Option C incorrectly describes bleeding gas for expansion rather than preheating combustion intake air. Option D is wrong because exhaust gases drive turbines rather than compressors in standard cycles.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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