Question 60. Is There A Difference In Mtd (mean Temperature Difference) Between "e" And "j" (divided Flow) Type Shell And Tube Heat Exchangers?
Answer : Divided flow (shell type J) does not have the same correction as the usual flow pattern (shell type E). Thermal design program make this correction factor mistake. True, there is very little difference at correction factors above 0.90. However, there is a difference at lower values. For example, Equal outlet temperatures Shell type "E" correction Fn = 0.805 Shell type "J" correction Fn = 0.775 Cold outlet 5F higher than hot outlet Shell type "E" correction Fn = 0.765 Shell type "J" correction Fn = 0.65 Contact us if you do not have MTD correction factor charts for divided flow. TEMA has one chart for a single shell but it gives high values for the above examples and it is hard to read in this range.
