The aim of this work is to specify which model of turbulence is the most adapted in order to predict the drag forces that a swimmer encounters during his movement in the fluid environment. For this, a Computational Fluid Dynamics (CFD) analysis has been undertaken with a commercial CFD code (Fluent). The problem was modelled as 3D and in steady hydrodynamic state. The 3D geometry of the swimmer...

the design and optimization of hydrocyclones using cfd techniques are gaining popularity and the key to a successful simulation lies with the accurate description of the high turbulent swirling behavior of the flow. this paper presents a detailed comparison between the omega rsm and the rng k–e turbulence model, which are both derived specially for modeling swirling or rotational flow, in the s...

A normal heartbeat is orchestrated by the stable propagation of an excitation wave that produces an orderly contraction. In contrast, wave turbulence in the ventricles, clinically known as ventricular fibrillation (VF), stops the heart from pumping and is lethal without prompt defibrillation. I review experimental, computational, and theoretical studies that have shed light on complex dynamical...

The magnetic field strength in molecular clouds is a fundamental quantity for theories of star formation. It is estimated by Zeeman splitting measurements in a few dense molecular cores, but its volume–averaged value within large molecular clouds (over several parsecs) is still uncertain. In this work we provide a new method to constrain the average magnetic field strength in molecular clouds. ...

Statistical language model is very important to speech recognition. To a system of special topic, domain dependent language model is much better than general model. There are two problems in traditional method to train topic dependent model: 1. The corpus of special topic is not as enough as general corpus. 2. An individual article always relates to more than one topics, traditional method has ...

In water supply systems, One of the most important components as safety unit and the current controller (Switching flow and regulate the amount of flow) used in the arrangement of lines of water. In this study, according to multiple ponds in Tanguiyeh dam water pipeline to industrial and mining company Gol Gohar Sirjan Butterfly valve used in these ponds using Fluent software simulation has bee...

The effects of some synthetic sweeteners on the rheological and physical properties of guar gum in dilute solutions were investigated.Measurements include the determination of intrinsic viscosity and the particle size, surface weighted mean [D3, 2], volume weighted mean [D4,3] and specificsurface area ofguar gum andsyntheticsweeteners mixtures. T...

This study aims to explain and elaborate a new model for the business environmental hostility in small and medium enterprises in the science and technology park in Kermanshah (Iran). The research method is a mixed method. Content analysis was used in the qualitative part, and a confirmatory factor analysis was used in the quantitative section. In the qualitative section for the environmental ho...

Gas holdup and bubble size are important parameters for simulation and designing in bubble column reactors. Because based on these parameters, the available gas-liquid interfacial area is defined for mass transfer. In this paper, the results of applying magnetic fields on the velocity field and volume fraction of gas holdup are reported. Hydrodynamics of the bubble column in the reactors is inv...

Elementary processes in free-decaying two-dimensional (2D) turbulence are examined by extensive analyses of fine structures in the density distribution of a magnetized pure electron plasma that is linearly unstable with the initial ring-shaped profile, deforms nonlinearly into patches of vortices, and relaxes into a single-peaked stable distribution via successive mergers among the patches. The...