Mixing fuel and air prior to the burner characterizes a/an ______________ burner?
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Answer: A. Premix
Explanation
A premix burner thoroughly mixes fuel gas and combustion air beforehand. This mixing occurs upstream prior to reaching the burner nozzle tip. Premixed reactants produce a short and intense combustion flame profile. Burner design dictates how fuel and oxidant interact before ignition occurs. Premixing ensures complete molecular contact between fuel and oxygen molecules. Flame stability and high combustion intensity are hallmarks of premix systems.
Premix burners are widely used in industrial boilers requiring high heat release rates. Careful design prevents flashback where flames propagate backward into the mixing chamber. These burners provide exceptional control over combustion stoichiometry and emissions. Outside mixing type burners combine fuel and air streams at the burner exit. Rotary burners utilize mechanical atomization for liquid fuel applications. Diffusion burners rely on slow mixing of fuel and air streams during combustion.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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