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Book part
Publication date: 2 October 2003

Walter C Borman, Jerry W Hedge, Kerri L Ferstl, Jennifer D Kaufman, William L Farmer and Ronald M Bearden

This chapter provides a contemporary view of state-of-the science research and thinking done in the areas of selection and classification. It takes as a starting point the…

Abstract

This chapter provides a contemporary view of state-of-the science research and thinking done in the areas of selection and classification. It takes as a starting point the observation that the world of work is undergoing important changes that are likely to result in different occupational and organizational structures. In this context, we review recent research on criteria, especially models of job performance, followed by sections on predictors, including ability, personality, vocational interests, biodata, and situational judgment tests. The paper also discusses person-organization fit models, as alternatives or complements to the traditional person-job fit paradigm.

Details

Research in Personnel and Human Resources Management
Type: Book
ISBN: 978-1-84950-174-3

Article
Publication date: 23 January 2019

Konrad Nering and Kazimierz Rup

For internal flows with small values of the Reynolds number, there is often at a considerable distance from the pipe inlet cross-section a change of the flow form from laminar to…

Abstract

Purpose

For internal flows with small values of the Reynolds number, there is often at a considerable distance from the pipe inlet cross-section a change of the flow form from laminar to turbulent. To describe this phenomenon of laminar-turbulent transition in the pipe, also parallel-plate channel flow, a modified algebraic intermittency model was used. The original model for bypass transition developed by S. Kubacki and E. Dick was designed for simulating bypass transition in turbomachinery.

Design/methodology/approach

A modification of mentioned model was proposed. Modified model is suitable for simulating internal flows in pipes and parallel-plate channels. Implementation of the modified model was made using the OpenFOAM framework. Values of several constants of the original model were modified.

Findings

For selected Reynolds numbers and turbulence intensities (Tu), localization of laminar breakdown and fully turbulent flow was presented. Results obtained in this work were compared with corresponding experimental results available in the literature. It is particularly worth noting that asymptotic values of wall shear stress in flow channels and asymptotic values of axis velocity obtained during simulations are similar to related experimental and theoretical results.

Originality/value

The modified model allows precision numerical simulation in the area of transitional flow between laminar, intermittent and turbulent flows in pipes and parallel-plate channels. Proposed modified algebraic intermittency model presented in this work is described by a set of two additional partial differential equations corresponding with k-omega turbulence model presented by Wilcox (Wilcox, 2006).

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

Abstract

Details

Freight Transport Modelling
Type: Book
ISBN: 978-1-78190-286-8

Book part
Publication date: 24 August 2004

Abstract

Details

Handbook of Transport Geography and Spatial Systems
Type: Book
ISBN: 978-1-615-83253-8

Abstract

Details

Recent Developments in Transport Modelling
Type: Book
ISBN: 978-0-08-045119-0

Article
Publication date: 7 September 2015

Toru Yamada, Jinliang Yuan and Bengt Ake Sunden

The purpose of this paper is to find out the applicability of the many-body dissipative particle dynamics (MDPD) method for various real fluids by specifically focusing on the…

Abstract

Purpose

The purpose of this paper is to find out the applicability of the many-body dissipative particle dynamics (MDPD) method for various real fluids by specifically focusing on the effects of the MDPD parameters on the MDPD fluid properties.

Design/methodology/approach

In this study, the MDPD method based on van der Waals (vdw) equation of state is employed. The simulations are conducted by using LAMMPS with some modifications of the original package to include the many-body features in the simulation. The simulations are investigated in a three-dimensional Cartesian box solution domain in which MDPD particles are distributed. In order to evaluate the MDPD liquid characteristics for a stationary liquid film, self-diffusivity, viscosity, Schmidt number (Sc) and surface tension, are estimated for different MDPD parameters. The parameters are carefully selected based on previous studies. A set of single-droplet simulations is also performed to analyze the droplet characteristics and its behavior on a solid-wall. Besides, the relationship between the characteristic length in the DPD simulations and scaling parameters for the stationary liquid-film case is discussed by employing the Ohnesorge number.

Findings

The results show that the liquid properties in the MDPD simulations can be widely ranged by varying the MDPD parameters. The values are highly influenced by the many-body feature in the conservative force which is not included in the original DPD method. It is also found that the wetting ability of the MDPD fluid on solid walls can be easily controlled by changing a many-body parameter. The characteristic length between the MDPD reduced unit and real unit is related for the stationary liquid-film case by employing the Ohnesorge number.

Originality/value

The present parametric study shows that the liquid properties in the MDPD method can vary by carefully controlling the MDPD parameters, which demonstrates the high-potential applicability of the method for various real fluids. This will contribute to research areas in multi-phase transport phenomena at nano and sub-micron scales in, for example, fuel cells, batteries and other engineering devices involving porous media.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 25 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

Book part
Publication date: 14 May 2013

Abstract

Details

Freight Transport Modelling
Type: Book
ISBN: 978-1-78190-286-8

Book part
Publication date: 1 October 2008

Abstract

Details

Recent Developments in Transport Modelling
Type: Book
ISBN: 978-0-08-045119-0

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