What is the typical specific heat value of superheated steam in kcal/kg·°C___________________?
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Answer: C. 0.5
Explanation
The specific heat of superheated steam over standard operating ranges is commonly approximated as 0.5 kcal per kilogram degree Celsius. This constant value provides a reliable engineering estimate for heat transfer calculations involving steam turbines. Steam requires approximately half the thermal energy per degree temperature rise compared to liquid water. Specific heat capacity defines the quantity of heat required to raise unit mass temperature by one degree. Superheated steam exists at temperatures higher than the saturation temperature corresponding to its pressure. While actual specific heat varies slightly with pressure and temperature, 0.5 is the standard textbook value.
Values like 0.1 are far too low for representing the thermal storage capacity of superheated steam. A specific heat of 0.3 underestimates the actual heat required to change superheated steam temperatures significantly. The value of 1.0 represents the approximate specific heat of liquid water rather than superheated steam.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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