Several rigorous turbulent models have been developed in the past years and it can be seen that more research is needed to reach a better understanding of their generality and precision by verifying their applications for distinct hydraulic phenomena; under certain assumptions. This survey evaluates the performance of Standard k-ε, Realizable k-ε, RNG k-ε, k-ω and RSM models in predicting flow ...

This study experimentally and numerically investigated the hydrodynamic characteristics of a 180° curved open channel over rough bed under condition constant downstream water depth. Three different sizes particles (the small, middle big cases based upon grain size diameter D50) were selected for flume tests. Three-dimensional instantaneous velocities obtained by acoustic Doppler velocimeter (AD...

In order to decrease the fluid dynamic forces of the U-bent tube with a circular section and avoid the occurrence of fluid-structure interaction problems, three-dimensional simulations of fluid flows around the tubes are carried out. In the case that the axis of the curved tube with the circular section is prevented from being normal to the direction of the flows approaching the tube, the forma...

Gradient flows for energy functionals have been studied extensively in the past. Well known examples are the heat flow or the mean curvature flow. To make sense of the term gradient an inner product structure is assumed. One works on a Hilbert space, or on the tangent space to a manifold, for example. However, it is possible to do without an inner product. The domain of the energy functionals c...

OBJECTIVE To determine optimal scissor blade design and surgical approach to facilitate obtaining a long optic nerve segment during enucleation procedures. METHODS Two hundred mock enucleations were performed with the use of a human child skull model and a silicone sphere to simulate an eye. Temporal and nasal approaches with scissor blades with noncurved, mildly curved, or strongly curved bl...

Direct numerical simulation of three-dimensional (3D) viscous flow in a wavy pipe is performed using the lattice Boltzmann approach, to study 3D flow features in a curved pipe with nonuniform curvature. We first validate the lattice Boltzmann approach by simulating a transient flow in a straight pipe. In a wavy pipe, it is shown that the pressure gradient necessary to drive the flow depends mor...