The problem table method

Convert the actual stream temperatures Tact into interval temperatures Tml by subtracting half the minimum temperature difference from the hot stream temperatures, and by adding half to the cold stream temperatures  

The use of the interval temperature rather than the actual temperatures allows the minimum temperature difference to be taken into account. ATmm = 10°C for the problem being considered see Table 3.4. 

Note any duplicated interval temperatures. These are bracketed in Table 3.4. 

Rank the interval temperatures in order of magnitude, showing the duplicated temperatures only once in the order see Table 3.5. 

Carry out a heat balance for the streams falling within each temperature interval For the nth interval  

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