Large-Eddy Simulation (LES) of high Reynolds number turbulent flow over an axisymmetric hill of height H = 2δ, where δ is the incoming turbulent boundary layer thickness, is presented in this paper. Surface mean pressure, flow visualization and mean velocity profiles are presented and compared with experiments. In general, good agreement is obtained for the surface mean pressure and axial flow ...

The effect of swirling on the flow characteristics of tubes with sudden expansion is experimentally examined by 3D particle image velocimetry(PIV) technique to determine velocity profiles. The swirling flow of water in sudden 1:2 axisymmetric expansion has been previously studied within a horizontal round tube. A tangential slot is used as a swirl generator for swirling flow, whereas a honey co...

Many studies have been carried out on the relationship between the occurrence and progression of circulatory diseases and hemodynamics. However, it is difficult to obtain accurate and detailed information on blood flow in the living body with existing experimental and numerical methods. The authors have previously proposed the Ultrasonic-Measurement-Integrated (UMI) simulation and shown that th...

Plumes due to localized buoyancy sources are of wide interest owing to their prevalence in many situations. This study investigates the transition from laminar to turbulent dynamics. Several experiments have reported that this transition is sensitive to external perturbations. As such, a well-controlled set-up has been chosen for our numerical study, consisting of a localized heat source at the...

In this paper, a spectral collocation approach based on the rational Chebyshev functions for solving the axisymmetric stagnation point flow on an infinite stationary circular cylinder is suggested. The Navier-Stokes equations which govern the flow, are changed to a boundary value problem with a semi-infinite domain and a third-order nonlinear ordinary differential equation by applying proper si...

e study the dynamics of elongated axisymmetric particles undergoing shear flow between two arallel planar walls, under creeping-flow conditions. Particles are modeled as linear chains of ouching spheres and it is assumed that walls are separated by a distance comparable to particle ength. The hydrodynamic interactions of the chains with the walls are evaluated using our artesian-representation ...

The surface of insulators accumulates charge during subject to high voltage stresses electrically.The surface charging causes deteriorations of electrical performance and durability of high voltage insulators in gas. In this paper, we describe a result of visual analysis of electric fields with accumulation charge on complex insulator surface to clear the effect of surface charging on the diele...