help pipesys

[nghiah5]

Hi all,
I'm student, I'm simulating piping with pipesys of NEO (hysys) but, I have seen that the temperature different within upstream and downstream very large :
T upstream : 18.33 oC
T downstream : 24.9
T ambient : 30 oC
I have read an example tutorial of hysys who talk about Pipesys :
T upstream : 45
T downstream ; 27.6 oC
T ambient 20 oC
I want know that I designed fault,or not?
The piping transfer heat very large with ambient, I want know which standard I can use in this case? (example thickness of coat prevent heat)
Every one can help me
Thank you and goodday to body
Nghĩa

[aissine]

i need elecrolytes license.