Question

In a bare pipe heat exchanger, surface fouling negatively affects:




pressure of the cooling medium


radiation heat transfer


heat transfer coefficient


cleaning of the tubes compared to finned tubes

Answer 1

Correct: pressure of the cooling medium and heat transfer coefficient.

Explanation:
- Fouling builds deposits that increase hydraulic resistance → higher pressure drop (affects the cooling medium pressure).
- Fouling adds thermal resistance and reduces convective heat transfer at the surface → lowers the overall heat transfer coefficient.
- Radiation heat transfer is negligible in typical pipe heat exchangers, so fouling does not meaningfully affect radiation.
- Bare tubes are generally easier to clean than finned tubes, so fouling does not make cleaning worse compared with finned tubes.