An experiment set-up is used to study wall deposition rate of particles on a rough surface in a turbulent channel flow. Deposition velocities for three classes of particles, namely, spherical glass particles, irregular shape polymer particles, and fibrous silicon particles are studied. The particle concentration at the test section was measured with the aid of an isokinetic probe in conjunction...

Over the last two decades, both experiments and simulations have demonstrated that transverse wall oscillations with properly selected amplitude and frequency can reduce turbulent drag by as much as 40 %. In this paper, we develop a model-based approach for designing oscillations that suppress turbulence in a channel flow. We utilize eddyviscosity-enhanced linearization of the turbulent flow wi...

Data are presented of experiments with turbulent open channel flow over rough surfaces and large relative submergence, which are conducted in two series with different geometric boundary conditions. During the experiments an oscillating fluid motion in the uppermost filter layer is visualised by the injection of a tracer dye. It is shown that this oscillating fluid motion is driven by highly un...

‎the water wave generation by wave paddle and a freely falling rigid body are examined by using an incompressible smoothed particle hydrodynamics (isph)‎. ‎in the current isph method‎, ‎the pressure was evaluated by solving pressure poisson equation using a semi-implicit algorithm based on the projection scheme and the source term of pressure poisson equation contains both of divergence free ve...

Free-surface wave effects on the turbulent boundary layer and wake of a surface-piercing slender body are investigated by measuring flow free-surface elevation around model in three different Froude number ( Fr) conditions—0.126, 0.282, 0.400. The is measured towed underwater stereoscopic particle image velocimetry system. At lowest Fr 0.126, there appears no significant pattern, but retards un...

this paper presents the results of numerical simulations of the laminar and turbulent flows inside diverging channels using random vortex methods (rvm). random vortex method is a mesh-free method which solves unsteady vorticity equation instead of solving navier-stokes equations directly to determine the velocity field. in this paper, the velocity potential, which is used as the initial conditi...

The airflow in the modeled glottal constriction was simulated by the solutions of the Navier-Stokes equations for laminar flow, and the corresponding Reynolds equations for turbulent flow in generalized, nonorthogonal coordinates using a numerical method. A two-dimensional model of laryngeal flow is considered and aerodynamic properties are calculated for both laminar and turbulent steady flows...

this paper presents a numerical study of local mass transfer coefficients in a 90° bend using the rng version of k–e model to include the influence of curvature on the turbulent transport. simulations were performed for flow through a 90°, 3-d bend for reynolds numbers of 13500, 90000, and 390000, schmidt numbers of 2.53 and 700 and curvature ratios of 1.5, 2, and 2.5. the differences between t...