Aspen heat exchanger simulation
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Question: When simulating a heat exchanger, I encountered a situation where the temperatures of both the cold and hot fluid streams increased. What could be the reason for this? I would be very grateful if you could help me figure it out!
This post was last edited by zhangfjj on 2011-5-23 17:15. Check whether the hot and cold logistics are connected correctly? The heat exchanger module seems to have specifications for the cold and hot streams.
Reply to 2# zhangfjj: Thank you. In the future, when setting specifications for simulated heat exchangers, everyone must be careful not to establish meaningless requirements, such as those related to vapor separation of the cold and hot fluid outputs. . .
How do I set the specifications for a heat exchanger? Could you send me an example? I urgently need the relevant materials! Thank you!
Reply to 4# Bingjing355: Search on the forum; there are many examples
There’s nothing wrong with specifying the gasification rate; you need to determine whether there is a temperature difference between the two feed streams, and also whether temperature reversal could occur as a result
Reply to 6# hj*ngfd: I checked later; since the vaporization fraction at the inlet and outlet of the cold and hot streams is 0 anyway, I specified that the vaporization fraction at the outlet of the hot stream should also be 0. That’s why such results appeared in the heat exchanger calculations. . .
Reply to 2# zhangfjj: That’s correct. The original poster just needs to reverse the order of the construction process, hot flow and cold flow
I’ve encountered a similar problem recently: after passing through the heat exchanger, the cold streams ended up being cooled down. The reason for this was that one of the cold streams had an excessively high load – by an order of magnitude – and the excessive amount of cooling energy caused the other cold streams to cool as well.
Most likely, the hot and cold flow directions are reversed, and unreasonable specified values have been set. The heater module of ASPEN fixes the inlet and outlet positions for cold and hot fluids, and they cannot be connected arbitrarily.
I think that’s right too; the heat flow wires were connected incorrectly