Abstract
Acoustic Doppler Velocimeters (ADV) experiments have been conducted over a fixed-dune to examine the effects of interacting dunes on the flow structure. The shape, dimensions and side angle of selected dunes were based upon previous empirical and field studies of dune morphology. Experiments were carried out on flow over a train of fixed 2D rough wall dunes in 12m flume. Dunes are developed in the height of 4 and 8 cm and in wavelength of 1m. This paper investigate the effect of lee angle (steep (>20°) and low (<10°) lee side angles) on separation zone and to study the effect of the dune bed roughness on turbulence structures and the length of separation zone calibrated RANS simulations was compared with experimental data. It is found that the models provide a good overall description measured by ADV. The separation zone also has a strong relation with lee angle and in the situation of low lee angle no flow separation was detected. Also increasing the dune height, roughness, water depth or velocity don't have an effective impact to separate the flow near the crest.
Original language | English |
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Pages (from-to) | 380-388 |
Number of pages | 9 |
Journal | European Journal of Scientific Research |
Volume | 62 |
Issue number | 3 |
Publication status | Published - Oct 2011 |
Keywords
- Dune
- Dune Height
- Lee Angle
- Numerical Modeling
- Reattachment point
- Separation Zone
ASJC Scopus subject areas
- Computer Science(all)
- Mathematics(all)
- Materials Science(all)
- Agricultural and Biological Sciences(all)
- Engineering(all)
- Earth and Planetary Sciences(all)