How does the pressure of steam exiting a reheater compare to its inlet pressure _________________?
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Answer: B. less
Explanation
Steam experiences a pressure drop as it flows through a reheater due to frictional resistance. Fluid friction against the internal walls of the tubing inherently consumes a portion of total pressure. Energy losses across the heat exchanger tubing always result in lower exit pressure compared to inlet pressure. A reheater is a specific component in power plants designed to raise the temperature of partially expanded steam. Steam from the high-pressure turbine returns to the boiler to undergo reheating before entering intermediate turbines. Pressure drop is an unavoidable thermodynamic consequence of fluid transport through long, restricted conduit networks.
Option A suggests pressure increases, which violates basic fluid dynamics principles in constant-area piping. Option C implies zero friction losses, an unrealistic scenario for real compressible fluid flow systems. Option D introduces unnecessary complexity because frictional pressure drops universally occur in actual reheaters.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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