A numerical model is developed to determine the flow depth and discharge relationship for turbulent flows over vegetated flood plains. The model is based on the turbulent boundary layer similarity concepts developed for atmospheric and pipe flow hydraulics. Here, the Darcy–Weisbach formula is modified to account for vegetative resistance by application of surface roughness lengths developed fro...

Accurate measurements of fluid flow close to the free water-sided air-water interface are vital for a proper understanding and quantification of interfacial transport phenomena. Yet, these measurements are difficult to attain with current PIV or PTV based techniques. Moreover, the observed flow structures are highly turbulent, leading to large out-ofplane components in laser-sheet based approac...

Flood waves resulting from dam breaks and flash floods have been responsible for numerous losses. In the present study, sudden flood releases were investigated down a large flume with a succession of abrupt drops. A new experimental technique was developed to obtain instantaneous void fractions, bubble count rates and velocities using arrays of conductivity probes. The results showed the surge ...

We investigate spatial and temporal cross-correlations between streamwise and normal velocity components in three shear flows: a low-dimensional model for vortex-streak interactions, direct numerical simulations for a nearly homogeneous shear flow and experimental data for a turbulent boundary layer. A driving of streamwise streaks by streamwise vortices gives rise to a temporal asymmetry in th...

We present experimental, numerical, and theoretical studies of a vortex front propagating into a region of vortex-free flow of rotating superfluid 3He-B. We show that the nature of the front changes from laminar through quasiclassical turbulent to quantum turbulent with decreasing temperature. Our experiment provides the first direct measurement of the dissipation rate in turbulent vortex dynam...

Observations of turbulent kinetic energy (TKE) dynamics in the ocean surface boundary layer are presented here and compared with results from previous observational, numerical, and analytic studies. As in previous studies, the dissipation rate of TKE is found to be higher in the wavy ocean surface boundary layer than it would be in a flow past a rigid boundary with similar stress and buoyancy f...

In the laboratory we used an idealized rotorwash flow—an axisymmetric jet impinges normally on a packed bed of cohesionless particles—and measured the spatially varying flow field and entrainment flux under an axisymmetric jet over a range of jet exit velocities and bed materials. We found that the erosion of the bed is driven by turbulent surface shear stress, quantified by the turbulent kinet...

We consider the effects of distributed roughness on the boundary-layer transition over a rotating disk using both theoretical and experimental approaches. The theoretical approach further develops Yoon et al.’s method [Int. J. Heat Fluid Flow, 28, p262 (2007)] for obtaining the steady-flow solutions for a general surface distribution function. Full threedimentional stability analyses are conduc...

Electromagnetic braking (EMBr) greatly influences turbulent flow in the continuous casting mold and its transient stability, which affects level fluctuations and inclusion entrainment. Large eddy simulations are performed to investigate these transient flow phenomena using an accurate numerical scheme implemented on a graphics processing unit. The important effect of the current flow through th...

This paper reviews several aspects of liquid jet impingement cooling, focusing on research done in our lab at MIT. Free surface, circular liquid jet are considered. Theoretical and experimental results for the laminar stagnation zone are summarized. Turbulence effects are discussed, including correlations for the stagnation zone Nusselt number. Analytical results for downstream heat transfer in...