To lower the tube-side pressure drop while maintaining the same flow rate, the preferred heat exchanger is _______________?
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Answer: B. 1-1 heat exchanger
Explanation
A one-one heat exchanger utilizes single passes for both shell and tube fluids. Limiting the tube side to a single pass prevents excessive fluid acceleration and friction losses. Lower fluid velocity directly reduces the overall pressure drop experienced on the tube side. Heat exchanger pass configurations dictate how many times fluids traverse the core bundle. Multipass designs force fluid to reverse direction multiple times, increasing frictional pressure drop. Pressure drop in pipes is proportional to the square of the internal fluid velocity.
Pumping costs decrease significantly when low pressure drop exchangers are selected for viscous fluids. Chemical processing plants prioritize low pressure drops to avoid overloading upstream feed pumps. Designing efficient cooling loops requires balancing heat transfer coefficients against allowable pressure drops. A one-two exchanger features multiple tube passes that double the tube-side velocity and losses. Three-two exchangers introduce complex multi-pass routing that severely increases tube-side pressure drops. Two-four exchangers incorporate multiple passes on both sides, maximizing velocity and pressure drop.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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