Originally, two heat exchangers were used in series; now it is planned to change them to a parallel configuration. Will the heat exchange efficiency decrease as a result?
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Originally, two heat exchangers were used in series; now it is planned to change them to a parallel configuration. Will the heat exchange efficiency decrease as a result?
When the heat exchangers are connected in series, the flow velocity decreases slightly; the heat exchange area is equivalent to that of two heat exchangers combined. The water volume remains unchanged, while the outlet temperature increases significantly. The heat exchangers are connected in parallel, resulting in a slight increase in flow velocity; the heat exchange area is equivalent to that of two heat exchangers combined. The water volume is doubled, while the outlet temperature remains unchanged.
The heat exchange area remains unchanged anyway. It seems that process calculations are needed
If the flow rate remains unchanged, the heat exchange efficiency will decrease.
Changing from series to parallel configuration reduces the flow velocity through each heat exchanger plate, thereby lowering its heat transfer coefficient. However, the heat transfer temperature difference after parallel connection is greater than that in series connection. Without specific parameters, it is impossible to determine changes in its effectiveness. The original poster can calculate to see which has a greater impact, the heat transfer coefficient or the temperature difference.
1. There are many factors that determine the heat transfer efficiency, such as temperature difference, area, and heat transfer coefficient; the heat transfer coefficient is closely related to flow velocity. 2. By changing from a series configuration (assuming that in the original question it refers to series connection within the tubes or within the shell), to a parallel configuration, the flow velocity decreases and the K value drops, which does not necessarily result in an increase in the temperature difference. 3. It is necessary to carry out calculations to determine whether a change in the configuration is appropriate
Both of my heat exchangers are of the BJS1200-2.5-485-6/19-4 model, with a baffle spacing of 450 mm. How is this value calculated? Could you please provide the corresponding page numbers in the textbook?
Is it a shell-and-tube heat exchanger? What is a thermocouple medium?
The tube side is circulating water, while the shell side is propane (which enters directly for heat exchange after coming out of the depropanization tower); both the tube side and the shell side are connected in parallel.