Installing a shell-side baffle in a multi-pass shell-and-tube heat exchanger ______________ the overall heat transfer rate?
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Answer: A. Increases
Explanation
Shell side baffles force fluid to flow across the tube bundle in cross-flow patterns. Cross-flow mixing and turbulence significantly enhance the shell-side heat transfer coefficient. Improved turbulence breaks up stagnant boundary layers and boosts overall heat transfer rates. Shell-and-tube heat exchangers utilize baffles to support tubes and direct fluid flow. Optimal baffle spacing maximizes heat transfer while maintaining acceptable pressure drop limits. Turbulent flow regimes yield higher heat transfer coefficients than laminar parallel flow.
Industrial heat exchangers incorporate segmental baffles to improve thermal performance efficiency. Proper baffling prevents fluid bypassing and ensures uniform flow distribution across tubes. Enhancing heat transfer rates reduces the total surface area required for specific duties. Decreasing heat transfer rates would render heat exchanger designs inefficient and costly. Baffles intentionally alter flow paths and directly affect overall heat transfer performance. Baffle implementation consistently increases heat transfer rather than leaving it unaffected.
- Subject
- Engineering
- Category
- Chemical Engineering
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- —
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- medium
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