Abstract
A new method based on ultra-fast X-ray imaging was developed in this work for the investigation of the dynamics and the structures of complex two-phase flows. In this paper, cavitation was created inside a millimetric 2D Venturi-type test section, while seeding particles were injected into the flow. Thanks to the phase-contrast enhancement technique provided by the APS (Advanced Photon Source) synchrotron beam, high definition X-ray images of the complex cavitating flows were obtained. These images contain valuable information about both the liquid and the gaseous phases. By means of image processing, the two phases were separated, and velocity fields of each phase were, therefore, calculated using image cross-correlations. The local vapour volume fractions were also obtained, thanks to the local intensity levels within the recorded images. These simultaneous measurements, provided by this new technique, afford more insight into the structure and the dynamic of two-phase flows as well as the interactions between them, and hence enable to improve our understanding of their behaviour. In the case of cavitating flows inside a Venturi-type test section, the X-ray measurements demonstrate, for the first time, the presence of significant slip velocities between the phases within sheet cavities for both steady and unsteady flow configurations.
Keywords
cavitation;measurements;x rays;
Data
Language: |
English |
Year of publishing: |
2017 |
Typology: |
1.01 - Original Scientific Article |
Organization: |
UL FS - Faculty of Mechanical Engineering |
UDC: |
620.193.16:615.849.11(045) |
COBISS: |
15738139
|
ISSN: |
0723-4864 |
Views: |
292 |
Downloads: |
127 |
Average score: |
0 (0 votes) |
Metadata: |
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Other data
Secondary language: |
Slovenian |
Secondary keywords: |
kavitacija;meritve;rentgenski žarki; |
Type (COBISS): |
Article |
Embargo end date (OpenAIRE): |
2018-11-01 |
Pages: |
str. 1-22 |
Issue: |
ǂVol. ǂ58 |
Chronology: |
Nov. 2017 |
DOI: |
10.1007/s00348-017-2426-7 |
ID: |
12852167 |