Is it reasonable for a heat exchanger to have high inlet and low outlet?
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This post was last edited by hezhong666666 on 2017-1-3 at 10:59. Heat exchanger: Coiled tube shell and tube heat exchanger. Hot fluid stream (shell side): Syngas, low inlet high outlet (N3 inlet, N4 outlet); inlet temperature: 120, outlet temperature: 90, operating pressure: 3 MPa. Cold fluid stream (tube side): Deionized water, high inlet low outlet (N1 inlet, N2 outlet); inlet temperature: 40, outlet temperature: 110, operating pressure: 9 MPa. Note: The deionized water is pumped through the heat exchanger to supply water to the steam drum. Is it reasonable to design the deionized water flow to be high inlet low outlet? Will there be air resistance?
Water at 110° won’t boil and vaporize at a pressure of 9MPA, right?
Isn’t that the opposite? For cold streams, it should be low in and high out, while for hot streams, it should be high in and low out.
Isn’t gas-phase condensation meant to occur from high pressure to low pressure? You’ve got it backwards
This is the design data provided by the design institute. The heat exchanger has already been manufactured, and we would like the design institute to redesign and remanufacture it, but they say that it meets the process requirements. We’re not sure whether the design institute is trying to deceive us.
This is another heat exchanger; its flow diagram is the same, and it is also designed with high inlet and low outlet flow: Coiled tube shell heat exchanger. Hot fluid stream (shell side): syngas, high inlet and low outlet flow (N3 in, N4 out); inlet temperature: 320, outlet temperature: 240, operating pressure: 3 MPa. Cold fluid stream (tube side): deionized water, high inlet and low outlet flow (N1 in, N2 out); inlet temperature: 40, outlet temperature: 200, operating pressure: 9 MPa. Note: The deionized water is pumped through the heat exchanger to supply water to the steam drum. Is it reasonable to design the deionized water flow to have a high inlet and low outlet flow?
It has been confirmed that it was indeed a design flaw, and the manufacturer has agreed to make the corrections!
This post was last edited by ylb913 on 2017-1-3 at 20:24. Since I was replying using a tablet or phone and then switched to the desktop version, I spent some effort typing my reply, only for it to suddenly turn into a bunch of garbled characters – it’s really frustrating. I have to re-edit the input once again. There are many other things that are impressive, but let’s focus on the topic of this post: many design firms these days keep bringing in young people, emphasizing high educational qualifications; many of them have master’s degrees, but lack practical experience, and it’s quite common for them to have incorrect design concepts. The main problem is that the managers are only focused on making money and don’t carefully examine the drawings; moreover, they refuse to admit their mistakes.