The mode of heat transfer where fluid motion is driven by pressure variations created through external work is termed_______________?
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Answer: C. Forced convection
Explanation
Forced convection requires external mechanical devices like pumps or blowers to drive fluid motion across solid boundaries. Fluid movement created through artificial pressure variations clearly distinguishes forced convection from natural buoyancy effects. External work input significantly enhances fluid velocity and turbulent mixing compared to purely thermally driven flows. Convective heat transfer involves the combined mechanisms of fluid conduction and macroscopic bulk fluid motion. Pumps and compressors supply the necessary mechanical energy to establish forced flow regimes inside piping. Dimensionless numbers like the Reynolds number are essential for characterizing forced convection heat transfer coefficients.
Automotive engine cooling systems utilize water pumps to force coolant through radiators and engine blocks. Heating, ventilation, and air conditioning systems rely on motorized blowers to distribute conditioned air indoors. Industrial chemical reactors employ forced circulation loops to maintain uniform temperatures and reaction rates. Radiation transfers thermal energy via electromagnetic waves without requiring any intervening physical medium whatsoever. Natural convection relies entirely on density gradients and buoyancy forces rather than external mechanical work. Conduction is the direct microscopic transfer of thermal energy through stationary solid or fluid media.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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