Inserting a longitudinal baffle down the shell of a shell-and-tube exchanger forces the shell-side fluid to travel _____________ through the unit ?
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Answer: B. Twice
Explanation
Longitudinal baffles divide the shell cavity into two distinct flow compartments from inlet to outlet. Fluid must travel down the first compartment and return through the second compartment. This physical partition forces the shell-side fluid to traverse the unit exactly twice. Baffles inside shell-and-tube exchangers direct fluid paths to maximize crossflow turbulence. Longitudinal baffles run parallel to the tubes, creating two-pass shell-side configurations. Multi-pass shell designs improve mean temperature differences in low-flow applications.
Specialized chemical processes use longitudinal shell baffles to increase shell-side fluid velocities. Fabricating partitioned shells requires careful sealing to prevent fluid bypass around the baffle. Enhanced shell-side paths help achieve required thermal duties without increasing unit lengths. Traveling once describes standard unbaffled or single-pass shell-side flow configurations. Traveling thrice requires complex internal partitioning that is rarely used in standard manufacturing. Four passes on the shell side require multiple longitudinal dividers rarely found in standard units.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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