Plate heat temperature correction factor

The temperature correction factor, Ft, will normally be higher with plate heat exchangers, as the flow is closer to true counter-current flow. 

Figure 12.62. Log mean temperature correction factor for plate heat exchangers (adapted from Raju and Chand (1980))...

A further advantage of the plate heat exchanger is that the effective mean temperature difference is usually higher than with the tubular unit. Since the tubular is always a mixture of cross and contra-flow in multi-pass arrangements, substantial correction factors have to be applied to the log mean temperature difference (LMTD). In the plate... 

For plate heat exchangers it is convenient to express the log mean temperature difference correction factor, F, as a function of the number of transfer units, NTU, and the flow arrangement (number of passes) see Figure 12.62. The correction will normally be higher for a plate heat exchanger than for a shell and tube exchanger operating with the same... 

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