What type of draft system is characterized by a balanced draft furnace_________________________?
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Answer: B. induced draft fan and forced draft fan
Explanation
A balanced draft system combines both a forced draft fan and an induced draft fan. The forced draft fan pushes combustion air efficiently through the furnace grates. Meanwhile, the induced draft fan pulls spent exhaust gases safely out through the chimney. Furnace draft systems maintain proper airflow rates required for complete fuel combustion. Using dual fans creates a slightly negative pressure inside the furnace combustion chamber. This negative pressure prevents dangerous hot flue gases from leaking into the boiler room.
Large industrial steam power plants utilize balanced draft systems for optimal boiler operation. Modern utility boilers require precise airflow control to maximize thermal efficiency and output. This setup handles high resistance across air preheaters and emission control equipment. Using only an induced draft fan and chimney relies solely on negative pressure extraction. An induced draft fan combined with a forced draft fan provides the true balanced setup. Forced draft fans alone maintain positive furnace pressure, risking harmful gas leakage.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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