A _____________ heat exchanger is optimal when the shell-side fluid temperature significantly exceeds that of the tube-side?
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Answer: B. U-tube
Explanation
U-tube heat exchanger designs allow independent thermal expansion of individual tubes within the shell. Large temperature differences between shell-side and tube-side fluids create severe thermal stress risks. U-bend configurations eliminate tube sheet joint failures caused by unequal thermal expansion rates. Shell and tube heat exchangers are widely used in industrial chemical processing plants. Fixed tube sheet exchangers lack flexibility to handle extreme temperature gradients across fluids. Thermal expansion causes significant mechanical stress in heat exchanger tubes and headers.
Refinery distillation overhead condensers operate reliably using U-tube heat exchanger configurations. High-temperature chemical reactor effluent coolers require designs that accommodate thermal expansion. Power plant feedwater heaters utilize flexible tube geometries to prevent thermal fatigue damage. Single pass fixed tube sheet exchangers experience high thermal stresses under large temperature differences. Three pass fixed tube sheet designs also lack the necessary thermal expansion flexibility. Selecting none of these is incorrect because U-tube designs successfully resolve thermal stress issues.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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