What is the purpose of incorporating a reheat cycle within a steam power plant________________?
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Answer: B. increase thermal efficiency
Explanation
Reheating steam between turbine expansion stages increases the average temperature of heat addition. This process also keeps steam quality high, preventing moisture damage in low pressure blades. Therefore, incorporating a reheat cycle within a steam power plant increases thermal efficiency. Steam is extracted halfway through the turbine and sent back to the boiler for reheating. Reheated steam expands further through the low pressure turbine without excessive moisture. Higher average cycle temperatures directly improve overall thermodynamic performance.
Large modern fossil fuel power plants routinely employ single or double reheat cycles. Protecting turbine blades from water droplet erosion saves millions in maintenance costs. Engineers balance reheat piping pressure drops against efficiency gains. Utilizing flue gas heat happens in economizers, while reheating uses furnace radiant heat. Condenser performance is managed by cooling water rather than the steam reheat cycle. Reducing heat loss is secondary to increasing the average temperature of heat addition.
- Subject
- Engineering
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- Electrical Engineering
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- —
- Difficulty
- medium
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