ArTS Archivio della ricerca di Trieste
ArTS è il sistema di gestione integrata dei dati della ricerca adottato dall' Università degli Studi di Trieste
EnglishFor high temperature industrial processes, or usual thermo-mechanical energy conversion plants, the results of the exergy analysis show very low differences if the higher or the lower, possible value for the ambient temperature T ° is chosen. This is not true if energy processes at a temperature close to ambient temperature are considered, for instance thermal solar systems, or low temperature district heating systems. The paper revises the derivation of flow and nonflow exergy if T° and P° vary in time, highlighting the case of periodic variations. As a result, besides the terms analogous to the well known ones, in the expression of the exergy balance of a generic control volume, two additional terms appear, that take into account exactly the available work (exergy) destruction related to the variation of ambient condition during the considered time interval. Then, the theoretical opportunity of taking advantage of the effects of variable T° (like exergy increment of thermal storag es, or creation of “hot” and “cold” reservoirs without work expense) are discussed and their physical limitations are outlined.
| Titolo: | Exergy analysis with variable ambient conditions |
| Autori: | |
| Data di pubblicazione: | 2016 |
| Abstract: | For high temperature industrial processes, or usual thermo-mechanical energy conversion plants, the results of the exergy analysis show very low differences if the higher or the lower, possible value for the ambient temperature T ° is chosen. This is not true if energy processes at a temperature close to ambient temperature are considered, for instance thermal solar systems, or low temperature district heating systems. The paper revises the derivation of flow and nonflow exergy if T° and P° vary in time, highlighting the case of periodic variations. As a result, besides the terms analogous to the well known ones, in the expression of the exergy balance of a generic control volume, two additional terms appear, that take into account exactly the available work (exergy) destruction related to the variation of ambient condition during the considered time interval. Then, the theoretical opportunity of taking advantage of the effects of variable T° (like exergy increment of thermal storag es, or creation of “hot” and “cold” reservoirs without work expense) are discussed and their physical limitations are outlined. |
| Handle: | http://hdl.handle.net/11368/2934376 |
| ISBN: | 978-961-6980-15-9 |
| Appare nelle tipologie: | 4.1 Contributo in Atti Convegno (Proceeding) |
File in questo prodotto:
| File | Descrizione | Tipologia | Licenza | |
|---|---|---|---|---|
| P311_EXERGY ANALYSIS WITH VARIABLE AMBIENT CONDITIONS.pdf | Articolo principale | Bozza finale post-referaggio (post-print) | Copyright Editore | Administrator Richiedi una copia |
