Model developed from performance curves are dynamic models?

  • #1
81
2
I am trying to model a real heat exchanger in simulink. I dont have the geometry data. But I have UA curve with me. If I have developed the model with UA curve, will it be dynamic in nature?
 

Answers and Replies

  • #2
BvU
Science Advisor
Homework Helper
14,480
3,752
Nope.
 
  • #3
81
2
Nope.
Do you think, is it because the test data gives the details of only at steady state ?
 
  • #4
BvU
Science Advisor
Homework Helper
14,480
3,752
I do. UA is an instantaneous value, a curve makes it a function of something.

On the other hand, dynamics of heat exchangers aren't often a focus (except perhaps in textbooks): I've always seen them treated as instantaneously reacting devices because the heat content of vessels, columns and reactors and such was so much greater. Do you have a particular application in mind ?

@Chestermiller : any experience ? -- and shouldn't we let the OP add some more context ?
 
  • #5
21,390
4,803
I do. UA is an instantaneous value, a curve makes it a function of something.

On the other hand, dynamics of heat exchangers aren't often a focus (except perhaps in textbooks): I've always seen them treated as instantaneously reacting devices because the heat content of vessels, columns and reactors and such was so much greater. Do you have a particular application in mind ?

@Chestermiller : any experience ? -- and shouldn't we let the OP add some more context ?
I agree. I think we need to hear more details. But it might be a decent approximation if UA where used in a dynamic case based on the instantaneous conditions. It depends.
 
  • #6
81
2
I do. UA is an instantaneous value, a curve makes it a function of something.

On the other hand, dynamics of heat exchangers aren't often a focus (except perhaps in textbooks): I've always seen them treated as instantaneously reacting devices because the heat content of vessels, columns and reactors and such was so much greater. Do you have a particular application in mind ?

@Chestermiller : any experience ? -- and shouldn't we let the OP add some more context ?
My end objective is to make complete simulink model for rotory air compressor. So this heat exchanger will become one of the subsystem in my model. Can you tell me, if I am using a heat exchanger modeled with this approach can mimic the actual system functionality?
 
  • #7
BvU
Science Advisor
Homework Helper
14,480
3,752

Related Threads on Model developed from performance curves are dynamic models?

Replies
7
Views
6K
Replies
1
Views
679
  • Last Post
Replies
1
Views
653
  • Last Post
Replies
3
Views
14K
  • Last Post
Replies
3
Views
4K
  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
15
Views
2K
  • Last Post
Replies
1
Views
2K
Top