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Calibration of the oscillating screen viscometer
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Berg, Robert F. Moldover, Michael R. |
| Copyright Year | 1993 |
| Description | We have devised a calibration procedure for the oscillating screen viscometer which can provide the accuracy needed for the flight measurement of viscosity near the liquid-vapor critical point of xenon. The procedure, which makes use of the viscometer's wide bandwidth and hydrodynamic similarity, allows the viscometer to be self-calibrating. To demonstrate the validity of this procedure we measured the oscillator's transfer function under a wide variety of conditions. We obtained data using CO2 at temperatures spanning a temperature range of 35 K and densities varying by a factor of 165, thereby encountering viscosity variations as great as 50%. In contrast the flight experiment will be performed over a temperature range of 29 K and at only a single density, and the viscosity is expected to change by less than 40%. The measurements show that, after excluding data above 10 Hz (where frequency-dependent corrections are poorly modeled) and making a plausible adjustment to the viscosity value used at high density, the viscometer's behavior is fully consistent with the use of hydrodynamic similarity for calibration. Achieving this agreement required understanding a 1% anelastic effect present in the oscillator's torsion fiber. |
| File Size | 1363948 |
| Page Count | 33 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20030071658 |
| Archival Resource Key | ark:/13960/t0vq7vk2c |
| Language | English |
| Publisher Date | 1993-12-07 |
| Access Restriction | Open |
| Subject Keyword | Viscosity Calibrating Transfer Functions Temperature Gradients Xenon Carbon Dioxide Oscillations Viscometers Critical Point Density Distribution Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
