EuroSun2008-2
Heat exchanger model validation
In order to tune the heat exchanger model with the experimental data, the heat transfer coefficients need to be identified. For one exchanger, four heat transfer coefficients are defined: one for each zone on the refrigerant side, and one for the secondary fluid.
In the evaporator, two different heat exchangers were used. In total, eight parameters were therefore necessary to describe the set of exchangers in series.
|
|
For given supply and exhaust temperature conditions, the condenser model predicts its pressure. Figure 7 shows that this pressure is predicted with a relative error of about 3%.
In the evaporator, the pressure is imposed by the expander and the feed pump. Given its supply temperature and the saturation pressure, the model predicts the heat flow and the exhaust temperature. Figure 8 shows that the heat flow is predicted with an error lower than 2%.
The validation of the models is necessary to ensure that the calculated results are valid. Furthermore it is to proof what differences consist due to the assumptions made in the …
Data gathered in the framework of the IEA Task 33/IV include comprehensive information about the geographical distribution of the solar thermal plants, the industrial sectors addressed, the specific processes, the …
J. Koschikowski*, M. Wieghaus*, M. Rommel*, Vicente Subiela Ortin**, Baltasar Penate Suarez**, Juana Rosa Betancort Rodriguez** * Fraunhofer Institute for Solar Energy Systems ISEHeidenhofstr.2,79110 Freiburg, GermanyTel +49-761-4588-5294Fax +49-761-4588-9000email ioako@ise. fhg. …