A shell-and-tube heat exchanger with a longitudinal baffle, as illustrated schematically in Figure 1a, may be treated as two units coupled in a parallel flow or in a counter flow.

Figure 1 A shell-and-tube heat exchanger with a longitudinal baffle; shell-side nozzles are located near the tube side nozzles

Example: The heat exchanger in Figure 1a has from each side of the longitudinal baffle two tube-side passes and two segmental baffles. it is required to calculate the heat exchanger effectiveness given the following data:

• Cell effective E_c = 0.4

• Ratio of heat capacity rates R = 1

The calculations are as follows.