| Zugriffsnummer | 46388 |
| Dokumenttyp | Zeitschriftenartikel |
| Peer Review | mit Peer Review |
| Sprache | Englisch |
| Titel | The thermal diffusivity of glass sieves: II. Gas-saturated frits |
| Autor(in); Institution |
Hammerschmidt, Ulf; PTB-Braunschweig, retired staff
Abid, Muhammad; Department of Mechanical Engineering, COMSATS University Islamabad, Islamabad, PAKISTAN
|
| Quelle/Jahr | International Journal of Thermophysics: 42 (2021), 6, 1 - 19 |
| Artikelnummer | 95 |
| ISSN | 0195-928X (PRINT) ; 1572-9567 (ONLINE) |
| DOI | |
| Verlag | Dordrecht: Springer |
| Freie Schlagworte | Dissolved helium ; Frit ; Glass sieve ; Gas saturant ; Porous medium ; Thermal conductivity ; Thermal porosity ; Transient hot-bridge method |
| Zusammenfassung | The thermal difusivity of gas-saturated glass sieves (frits) of porosities between 20 % and 48 % is presented as measured at room temperature and ambient pressure. The saturants cover a range in thermal difusivity from 20.63 × 10-6 m2· s -1 to 172 × 10-6 m2 ⋅s -1. The experiments were carried out using a transient hot-bridge instrument of an expanded uncertainty of 5 % to 10 %. It turned out that all measured thermal difusivities of the gas-saturated frits (1) are smaller than that of the borosilicate glass the frits are made from and (2) are completely diferent from the thermal difusivities of the liquid-saturated frits. Both these discrepancies can be attributed to characteristic properties of the matrix and not directly to the saturants. The frst divergence results from thermal tortuosity that lengthens the pathway of heat through the matrix, whereas the second arises from dissolved He that enhances the transport of heat through the matrix. |
| Themenbereich der Metrologie | Durchfluss |