[Gerard]

uhm i also have a question about heat exchanger, we are using a double pipe tubular heat exchanger by armfield model HT30X and HT31X the thermocouple where arranged as follows
T1=hot water inlet T2=midpoint of the hot water flow T3=hot water outlet
the hot water flows inside a stainless steel pipe and the cold water flowed in the acrylic annulus..
our problem arises when we lowered the temp from 75 centigrade to 65,55 and 45 centigrade our reading was different from that of 75 centigrade cause T2 was greater than T1 by a factor of about 1 to 1.5 centigrade i am really confused by the data now our temperature flow profile is different compared to the literatures we are using(Geankoplis,and McCabe) what might be the problem....
however the equipment was in the department for about 9 years or so could this be that the equipment needs recalibration(but we are told that the equipment was newly recalibrated) or is there something wrong with the thermocouple?the reading at 75 centigrade was quite fine anyway...
or does this mean that our department should buy a new one?

[Donaldson Tan]

Can you post your experimental data, labelling the T1 with its corresponding T2 and T3?

[Gerard]

Can you post your experimental data, labelling the T1 with its corresponding T2 and T3?

our data journal is with the senior students they are also trying to figure out the problem maybe i will post it by monday because i said to the other group that we need to see thier data after they use this equipement if the data is consistent with ours then its time to consult the experts(you)
thank you very much.....maybe a second run will prove something...
thank you
-artificial student