showing 5 related works from this author
Identifying wave and turbulence components in wind-driven shallow basins
2012
Wind-induced waves play an important role in shallow lake hydro- and sediment dynamics. That is why field measurements are important for the validation of their estimation methods, especially in shallow waters. In the first part of the present paper a method is introduced to improve the interpretation of the measured data, applicable both for pressure and velocity data. Replacing the turbulence-affected tail of the measured spectrum with a fitted power function causes a considerable 8-10% difference in the derived bulk wave parameters so this procedure is worth to be done. In the second part an appropriate technique to obtain wave features from 3D velocity time series will be described. The…
Three-dimensional numerical analysis of turbulent wind-induced flows in the Lake Balaton (Hungary)
2004
Numerical simulation of internal boundary-layer development and comparison with atmospheric data
2006
A finite-volume numerical model is employed to investigate the adaptation of the atmospheric boundary layer to a change in the underlying surface roughness, such as that existing in the transition from land to the free surface of a water body. Numerical results are validated by comparison with neutral stratification atmospheric data and compared with the internal boundary-layer (IBL) heights computed using a number of existing empirical formulae. The numerical analysis allows an extension of the fetch range in which the existing formulae, calibrated only by comparison with short fetch data, may be applied. An argument is offered that the spatial variability of the water surface roughness sh…
Detecting the chaotic nature of advection in complex river flows
2012
In order to detect signatures of chaotic advection in river surface motion, surface buoys equipped with GPS were deployed in a field experiment in River Danube, Hungary. The buoys were released in the vicinity of groynes where complex mixing processes occur. A detailed analysis of the trajectories was carried out, focusing on the time evolution of the distance between buoy pairs. The analysis included the determination and comparison of local Lyapunov exponents and prediction times of finite-time hyperbolic behaviour, which is related to strong mixing. Despite of the small number of applied buoys we found evidence on Lagrangian chaos in the wake of a groyne field. In order to supplement the…