In multi-pass shell-and-tube heat exchangers, the temperature drop experienced by the fluid _______________?
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Answer: B. And the wall are proportional to individual resistances
Explanation
Temperature drops across series thermal resistances are directly proportional to their individual resistance values. Electrical resistance analogies apply perfectly to steady state heat transfer through composite layers. Larger individual thermal resistances sustain proportionally larger temperature drops under constant heat flux. Thermal resistance network analysis simplifies multi-layer heat conduction and convection problems. Fourier and Newton laws combine to relate heat flux directly to thermal resistance sums. Multi-pass exchangers establish multiple boundary layers with distinct localized resistance values.
Insulating composite walls requires calculating individual layer temperature drops to prevent condensation. Fouling layers in heat exchangers introduce high thermal resistance and large temperature drops. Thermal design engineers use resistance proportionality to select appropriate wall thickness limits. Inversely proportional relationships contradict steady state thermal resistance network equations. Stating they are unrelated ignores the fundamental analogy between electrical and thermal circuits. Option D is incorrect because statement B correctly describes thermal resistance proportionality.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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