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The important design and operating considerations for Extended-Surface Compact Heat Exchangers are: (1) Both fluids may have high or low heat transfer coefficients (2) As the tubes are very narrow (low DH), the fluid used should not be corrosive as effective cleaning of tubes is not possible. (3) The fluid pressure drop calculation is important as a regulatory method to ensure long life of the tubes. (4) Unlike shell and tube type heat exchangers, these are limited when it comes to operating pressure and temperature.

The important design and operating considerations for Extended-Surface Compact Heat Exchangers are: (1) Both fluids may have high or low heat transfer coefficients (2) As the tubes are very narrow (low DH), the fluid used should not be corrosive as effective cleaning of tubes is not possible. (3) The fluid pressure drop calculation is important as a regulatory method to ensure long life of the tubes. (4) Unlike shell and tube type heat exchangers, these are limited when it comes to operating pressure and temperature. Correct Answer (2), (3), (4)

For the design of Extended-Surface Compact Heat Exchangers, the given statements 2, 3, 4 are correct and important. Atleast one fluid should have low heat transfer coefficient and we should consider cleaner fluid to avoid clogging of narrow pipes.

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