A shell-and-tube heat exchanger has one pass on the shell side and two passes
on the tube side (i.e.al-2shell and tube heat exchanger). It is being used for oil
cooling. The oil flows in the tube side. It enters at 1120C and leaves at 78 0C
The shell-and-tube fluid is water at a flow rate of1.35 kg/s, entering at 360C and
leaving at 78 0C. The heat capacity of water is 4180j/(kg. K), and the overall
heat transfer coefficient for the heat exchanger is 350 W/(m2.K). The geometry
factor, F is 1.15. Determine the heat transfer area required for the unit.
In Figure 5.18, baffles are placed within the shell of the heat exchanger firstly to support the tubes, preventing tube vibration and sagging, and secondly to direct the flow to have a higher heat transfer coefficient. The distance between two baffles is baffle spacing.
Shell-and-tube heat exchangers can have multiple passes, such as 1-1, 1-2, 1-4, 1-6, and 1-8 exchangers, where the first number denotes the number of the shells and the second number denotes the number of passes. An odd number of tube passes is seldom used except the 1-1 exchanger. A 1-2 shell-and-tube heat exchanger is illustrated in Figure.