Guideline for selecting tube or shell side fluid

l Guideline for selecting tube or shell side fluid 

Preferred tube side fluid (1) fouling fluid except U-lubes, since it is easier to dean tubes, and has less stagnant areas. (2) corrosive fluid, since tubes are less expensive to be replaced. (3) high pressure fluid, since tube can stand higher pressure. 

Preferred shell side fluid (1) low available pressure drop, since shell side has more space. (2) large flow rate, (3) boiling service, (4) more viscous fluid. 

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