CHARACTERISTICS OF SEPARATED CYLINDRICAL BOUNDARY LAYERS,
Abstract
In former publications, the frequency law for velocity fluctuations in the transition region of a jet was described. A frequency law for the so-called natural frequency could be found. The natural frequencies and their amplitude are not strictly periodical and therefore only mean values can be measured. The more exact analysis of the natural frequency has shown that the frequency of the maximum amplitude coincides with the mean value of the natural frequency. To explain the distribution of the velocity fluctuations the phase velocity was measured and, based on this, the group velocity calculated. As the investigation of the natural frequency for one discrete frequency gives only mean values, the frequency of the vortex formation was stabilized by sound energy. The result is that the group velocity has a maximum in the region of the natural frequency, which means a maximum energy transport for this frequency. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1960
- Accession Number
- AD0652920
Entities
People
- O. Wehrmann
Organizations
- AGARD