giruffo
Chemical
- Jul 27, 2004
- 4
Dear sirs,
I would appreciate very much any suggestion about the way to evaluate the minimum temperature reached by the metal plates of a heat exchanger during emergency depressurization (i.e. in case of emergency the system is isolated and vented so to reach 100 psia in 15 minutes)
My heat exchanger is a PCHE (printed circuit heat exchanger) type, working with cross flow streams.
I think to be quite experienced with the "depressurization" routine of Hysys that can calculate fairly well the wall temperature of a vessel or of a pipe during depressurization, using the detailed heat exchange option.
Nevertheless here the case is more complex. In fact:
1. cold side and hot side of the heat exchanger depressurize independently to separate blow down lines, but they influence each other from a thermal point of view. 2.The initial temperature is not homogeneous as in the case of a vessel but there is a temperature profile along the plates.
3. I have difficulties to bild up a model that evaluates the thermal inertia of metal mass, in fact hysys simulates the wall of a vessel, that is quite different respect to the configuration of a PCHE that has a "sponge-like" structure.
Thank you in advance to anybody that will try to give me a useful advice or that will indicate any useful technical paper related to the subject.
Best regards
giruffo
I would appreciate very much any suggestion about the way to evaluate the minimum temperature reached by the metal plates of a heat exchanger during emergency depressurization (i.e. in case of emergency the system is isolated and vented so to reach 100 psia in 15 minutes)
My heat exchanger is a PCHE (printed circuit heat exchanger) type, working with cross flow streams.
I think to be quite experienced with the "depressurization" routine of Hysys that can calculate fairly well the wall temperature of a vessel or of a pipe during depressurization, using the detailed heat exchange option.
Nevertheless here the case is more complex. In fact:
1. cold side and hot side of the heat exchanger depressurize independently to separate blow down lines, but they influence each other from a thermal point of view. 2.The initial temperature is not homogeneous as in the case of a vessel but there is a temperature profile along the plates.
3. I have difficulties to bild up a model that evaluates the thermal inertia of metal mass, in fact hysys simulates the wall of a vessel, that is quite different respect to the configuration of a PCHE that has a "sponge-like" structure.
Thank you in advance to anybody that will try to give me a useful advice or that will indicate any useful technical paper related to the subject.
Best regards
giruffo