Initial results of an ongoing Navier-Stokes Computational Fluid Dynamics study of horizontal axis tidal current turbine hydrodynamics are presented. Part of the underlying motivation is assessing the effects of the Reynolds number on turbine performance and loads in steady and unsteady flow regimes. The study aims at a) providing initial verification and validation of Navier-Stokes CFD for stea...

A controlled ex-vivo study of a simple, sinusoidally oscillating flow in a rigid, constant-area, smooth tube, has produced significant insight into the laminar-turbulent transition phenomenon. The development of turbulence was studied by analyzing the dynamic characteristics of the transition process; i.e., the velocity, growth rate, and intermittency which describe the generation and propagati...

This paper presents a technique used to accelerate the convergence of unsteady flows to a periodic steady state. The basis of this procedure is to assume the time period of the solution's oscillation and to transform both the solution and residual using a discrete Fourier transform. However, this paper also presents a method which iteratively solves for the time period during the process of cal...

Turbulent mixing exerts a significant influence on many physical processes in the ocean. In stably stratified Boussinesq fluid, this irreversible describes conversion of available potential energy (APE) to background (BPE). some settings APE framework is difficult apply and approximate measures are used estimate mixing. For example, numerical simulations turbulence often use triply periodic dom...

An elementary analytical fluid flow is composed by a geometric domain, a list of analytical constraints and by the function which depends on the physical properties, as Reynolds number, of the considered fluid. For this object, notions of laminar or weakly turbulent behavior are described using a simple mathematical model. 1 Elementary analytical fluid flows Let L a length unit and Ω̄ a closed d...

A survey of secondary flows of viscoelastic liquids in straight tubes is given including recent work pointing at striking analogies with transversal deformations associated with the simple shearing of solid materials. The importance and implications of secondary flows of viscoelastic fluids in heat transfer enhancement are explored. Recent new work by the author and colleagues of both the stead...

Laminar flow velocity profiles depend heavily on fluid rheology. Developing methods of laminar characterization, based low-field magnetic resonance (MR), contribute to the widespread industrial application MR technique in In this paper, we outline design a low-cost, palm-sized permanent magnet with 1H frequency 20.48 MHz measure flow. The consists two disk magnets, which were each tilted at an ...

The continuous development of spinning projectiles and other industrial applications has led to the need to understand the laminar boundary-layer flow and subsequent onset of transition over the general family of rotating spheroids. We begin by finding the laminar boundary-layer flow over a general spheroid. In particular, we distinguish between prolate and oblate spheroids and use an appropria...

Abstract This paper concerns a method and test set-up to measure the permeability of plates metal foams sets wire meshes used control flows in fluid filters other flow systems designed yield constant velocity distributions over large cross sections flows. The is based on considerations using Ergun equation describe pressure losses packages mono-dispersed spheres. One correlation suggested for k...

Resolvent analysis is a powerful tool in fluid mechanics, both for laminar and turbulent flows. Depending on application, computational cost still limiting factor. We develop parabolic method the calculation of low-frequency resolvent modes, associated with streaky structures, which can enable more than an order magnitude speed up compared to usual global calculations. The applied boundary laye...