Furnace charge heating rates do not depend upon the________________?
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Answer: A. Type of fuels viz. solid, liquid or gaseous
Explanation
Charge heating rates depend on thermal parameters like flue gas temperature. Wall emissivity and initial stock temperature also govern internal heating speeds. The physical fuel state has no direct bearing on the heat transfer rate. Heat transfer to stock relies on temperature gradients and surface radiation properties. Fuels release thermal energy through combustion regardless of being solid, liquid, or gas. Once combustion occurs, the resulting hot gas properties dictate the heating rate.
Furnace designers focus on temperature and emissivity to accelerate production throughput. Changing from gaseous to liquid fuel alters burner design but not internal heat transfer. Initial stock temperature dictates the early transient phase of the heating cycle. Flue gas temperature directly influences the driving thermal gradient for heat transfer. Emissivity of refractory walls determines how much radiation reaches the stock surface. Initial temperature of the charged stock directly affects heat absorption calculations.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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