Abstract The free surface at an air–water interface can provide information regarding bathymetric complexities, as well the subsurface flow. We present a comparison of performance two recent advances in light-based optical techniques for measurements, total internal reflection-deflectometry and moon-glade background-oriented schlieren, with more established method synthetic schlieren. make use ...

in the present work, an engineering method is developed to predict laminar and turbulent heating-rate solutions for blunt reentry spacecraft at hypersonic conditions. the calculation of aerodynamic heating around blunt bodies requires alternative solution of inviscid flow field around the hypersonic bodies. in this paper, the procedure is of an inverse nature, that is, a shock wave is assumed a...

Dispersion of large deformable droplets in turbulent channel flow is investigated: the fluids are considered of same density and viscosity for a broad range of plausible values of surface tension. Droplets much larger than the Kolmogorov length scale are released in a channel flow; the turbulent flow is computed with pseudo-spectral Direct Numerical Simulations (DNS), while phase interactions a...

energy equation for turbulent flow in a rotating system was derived in terms of second order correlation tensors, where the correlation tensors were functions of space coordinates, distance between two points and time. to reveal the relationship of turbulent energy between two points, one point was taken as origin of the coordinate system. due to rotation, the coriolis force played an important...

We study the long-time evolution of surface gravity waves on deep water excited by a stochastic external force concentrated in moderately small wave numbers. We numerically implemented the primitive Euler equations for the potential flow of an ideal fluid with free surface written in Hamiltonian canonical variables, using the expansion of the Hamiltonian in powers of nonlinearity of terms up to...

The dissipation rate of a Ncwtonian fluid with constant shear viscosity can be shown to include three constituents: dilatation, vorticity, and surface strain. The last one is found to make no contributions to the change of kinetic energy. These dissipation constituents are used to identify typical compact turbulent flow structures at high Reynolds numbers. The incompressible version of the simp...

Vortex formation from a horizontal cylinder coincident with a free surface of a shallow water flow having a depth of 25.4 mm was experimentally investigated using the particle image velocimetry technique. Instantaneous and time-averaged flow patterns in the wake region of the cylinder were examined for three different cylinder diameter values under the fully developed turbulent boundary layer c...

The application of a novel turbulent inflow generator is presented using a 3D Direct Numerical Simulation (DNS) method. For simulation the in-house 3D CFD program Free Surface 3D (FS3D) is applied, which solves the incompressible Navier Stokes Equations for flows with free surfaces using a Volume-of-Fluid (VOF) technique. Three different numerical setups are presented, demonstrating the wide ra...

On a stepped spillway, the steps contribute to some dissipation of the turbulent kinetic energy, while free-surface aeration can be very intense. The aim of this study is to investigate the two-phase flow properties on a gabion stepped spillway, including both free-surface and seepage flows, as well as the bubbly flow interactions at the gabion interface. Detailed measurements were conducted in...