[TRNSYS-users] overall heat transfer,pressure drop, controlling

[Florian Hafner <hafner@hoki.ibp.fhg.de>]

hi,

1) I have a problem  to verify the "Overall heat transfer coefficient of 
exchanger" of type 5b .
The heat exchanger i use,  has the temperature-spreading  primary 
85/38°C ,secondary 80/32°C and the power of 15kW.
Can anyone tell me ,how i get the "Overall heat transfer coefficient of 
exchanger"?

2) Can anyone tell me, if trnsys implicate the pressure drop caused by 
pipe and does this have an effect on the flow rate in trnsys ( i don´t 
think so) ?

3) To control the solar circle i use the Type2b old control strategy. 
(Upper dead band dT 10/lower dead band 2 ) Upper input temperature Th is 
the output temperature of the  collector, and  the  lower input 
temperature  Ti  should be the lowest temperatur of the tank . I´m using 
the tank type4e with 5 nodes . If i had understand it correctly, than 
node 1 is the top node ( hot input) and node 5 the bottom node (cold 
input). The type 4e gives as outputs "Temperature to heat source"  and 
"Temperature of node 1+-1" ,"...-2.",."....-3". So for the" lower input 
temperatur Ti"  of the controller  i can use " Temperature to heat 
source" as lowest temperature in the tank.

Thanks a lot for  your help
flo