| Zugriffsnummer | 38543 |
| Dokumenttyp | Zeitschriftenartikel |
| Sprache | Englisch |
| Titel | Use of controlled-clearance high-pressure balances with highly viscous pressure transmitting media |
| Autor(in); Institution |
Bandyopadhyay, A. K.; National Physical Laboratory, Pressure and Vaccum Section, New Delhi, INDIA
Hilsch, Peter; 3.13, Druckmessung, PTB-Braunschweig
Jäger, Jochen; 3.13, Druckmessung, PTB-Braunschweig
|
| Quelle/Jahr | PTB-Mitteilungen: 97 (1987), 4, 264 - 269 |
| ISSN | 0030-834X |
| Verlag | Braunschweig ; Wiesbaden: Vieweg |
| Zusammenfassung | It is shown that in the case of a nonlinear dependence of the zero-clearance pressure pz on the measured pressure p, controlled-clearance high-pressure piston-cylinder systems can be operated over large portions of their measurement range at constant jacket pressure pj. This suggests characterizing the effective area by the equation Ae = A0 (1 + λp - d · pj) with the deformation coefficient λ being defined as for "simple" piston-cylinder systems. It is confirmed experimentally that λ and d do not depend on the measured pressure of on the jacket pressure, despite the nonlinear dependence of pz on p that is observed with highly visvous pressure transmitting liquids. The standard pressure balance used to measure the parameters A0, λ and d of two controlled-clearance piston-cylinder systems has been checked against the mercury melting line. The measuring method is described and results are reported. If use is made of the mercury fixed point of the pressure scale, controlled-clearance high-pressure balances operated with viscous media can be characterized independent of a primary standard by measurement uncertainties of a few parts in 10000. This is of practical importance, since experience has shown that when using less viscous (diluted) pressure transmitting media, there is a danger of deterioration of the piston-cylinder system. |
