Aligning free surface properties in time-varying hydraulic jumps
نویسندگان
چکیده
Hydraulic jumps occur commonly in natural channels and energy dissipation systems of hydraulic structures the violent transition from supercritical to subcritical flows. They are characterised by large flow aeration, high turbulence strong fluctuations free surface jump toe. For measurements, fast-sampling, fixed-point instruments such as acoustic displacement meters (ADMs) wire gauges (WGs) used, while LIDAR technology is a relatively new method for recording instantaneous motions aerated While each these has been shown previously provide reasonable results basic advanced properties, differences between experiments remain unexplained. To systematically analyse differences, simultaneous laboratory were conducted. Good agreement three was obtained properties including elevations, fluctuations, skewness, kurtosis, frequencies, well integral time length scales. These indicate that any can be used albeit scales sensitive spacing instruments. A key finding this research repeated previous studies observed when using visual toe alignment. However, bias could resolved mean location recorded with LIDAR. Therefore, future fundamental processes should simultaneously measure more consistent across studies.
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ژورنال
عنوان ژورنال: Experimental Thermal and Fluid Science
سال: 2021
ISSN: ['1879-2286', '0894-1777']
DOI: https://doi.org/10.1016/j.expthermflusci.2021.110392