Under turbulent liquid flow conditions inside tubes, the tube-side heat transfer coefficient is directly proportional to ___________________?
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Answer: C. G0.8
Explanation
Dimensional analysis and empirical heat transfer correlations for turbulent pipe flow establish the Nusselt number dependence. The Dittus-Boelter equation shows that the convective heat transfer coefficient scales directly with Reynolds number to the 0.8 power. Mass velocity is directly proportional to the Reynolds number inside circular conduits under fully developed turbulent flow. Turbulent flow features chaotic fluid mixing with high momentum transfer compared to smooth laminar flow regimes inside tubes. Mass velocity represents the mass flow rate per unit cross-sectional area of the flow channel or heat exchanger tube. Convective heat transfer coefficients quantify how efficiently thermal energy passes between solid tube walls and flowing fluids.
An exponent of 0.2 underestimates the velocity dependence typically observed in turbulent convective heat transfer correlations. An exponent of 0.5 is characteristic of boundary layer laminar flow solutions rather than fully turbulent pipe flow. An exponent of 1.5 exceeds theoretical and empirical turbulent transport limits established by standard engineering correlations.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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