HEAT EXCHANGERS
Heat Transfer
Figure 9 Fluid Flow Direction
The temperature profiles of the two heat exchangers indicate two major disadvantages in the
parallel-flow design. First, the large temperature difference at the ends (Figure 10) causes large
thermal stresses. The opposing expansion and contraction of the construction materials due to
diverse fluid temperatures can lead to eventual material failure. Second, the temperature of the
cold fluid exiting the heat exchanger never exceeds the lowest temperature of the hot fluid. This
relationship is a distinct disadvantage if the design purpose is to raise the temperature of the cold
fluid.
HT-02
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