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The purpose of this paper is to present a new eddy‐viscosity formulation designed to exhibit a correct response to streamline curvature and flow rotation. The formulation is implemented into a linear k‐ ε turbulence model with a two‐layer near‐wall treatment in a commercial computational fluid dynamics (CFD) solver.

A simple, robust formula is developed for the eddy‐viscosity that is curvature/rotation sensitive and also satisfies realizability and invariance principles. The new model is tested on several two‐ and three‐dimensional problems, including rotating channel flow, U‐bend flow and internally cooled turbine airfoil conjugate heat transfer. Predictions are compared to those with popular eddy‐viscosity models.

Converged solutions to a variety of turbulent flow problems are obtained with no additional computational expense over existing two‐equation models. In all cases, results with the new model are superior to two other popular k‐ ε model variants, especially for regions in which rapid rotation or strong streamline curvature exists.

The approach adopted here for linear eddy‐viscosity models may be extended in a straightforward manner to non‐linear eddy‐viscosity or explicit algebraic stress models.

The new model is a simple “plug‐in” formula that contains important physics not included in most linear eddy‐viscosity models and is easy to implement in most flow solvers.

The present model for curved and rotating flows is developed without the need for second derivatives of velocity in the formulation, which are known to present difficulties with unstructured meshes.

In this work we present interrelations between different finite rotation parametrizations for geometrically exact classical shell models (i.e. models without drilling rotation). In these kind of models the finite rotations are unrestricted in size but constrained in the 3‐d space. In the finite element approximation we use interpolation that restricts the treatment of rotations to the finite element nodes. Mutual relationships between different parametrizations are very clearly established and presented by informative commutative diagrams. The pluses and minuses of different parametrizations are discussed and the finite rotation terms arising in the linearization are given in their explicit forms.

In recent international debates on auditing regulation, Spain has assumed a real prominence as a claimed practical example of where a policy of mandatory audit firm rotation did not work and was duly abolished. This study aims to provide an analysis of the implementation and subsequent removal of mandatory audit firm rotation in Spain in the 1990s.

This takes the form of historical analysis; the evidence in the paper derives from congressional hearings, financial newspapers and documents produced by the professional associations of auditors in Spain.

This paper demonstrates that at no stage was mandatory rotation of audit firms ever enforced on Spanish auditors. Further, the revision and subsequent removal of the Spanish law on mandatory audit firm rotation emerge as a rather politicized process, with no evident reference being made in the process of legislative reform to Spanish auditing experiences. The analysis also reveals that at the very time that Spain was being cited internationally for rejecting mandatory audit firm rotation, Spanish political parties and regulators were debating whether to “re‐introduce” such a regulation.

The clear implication of the paper is that considerable caution needs to be taken in today's international‐auditing arena, when analyzing the standpoints and claims made by professional associations and the evidence they provide to support their arguments for and against regulatory reform.

To understand the impact of job rotation on Nigerian university libraries and in libraries in general. Design/methodology/approach – L A survey of opinion in Nigerian university libraries. Professional librarians from seven university libraries were used as subjects for the study. Findings That most of the respondents have spent an appreciable period of time working in the libraries; a majority of the respondents have been rotated; most of the respondents see job rotation as opportunity to learn new skills followed by those who see it as opportunity to be acquainted with other operations/services of the library; most of the respondents adjust to the new post by studying handover notes/files of new departments but a majority of them are of the view that job rotation is not regular enough in their libraries.

The focus of the paper is practical rather than research‐oriented.

Suggestions are made on how job rotation could be improved upon in libraries.

There are few empirical studies of job rotation in the literature – this paper increases understanding of a little studied topic.

A simple beam element is developed for the solution of large deflection problems. The total Lagrangian formulation is based on the kinematic relations proposed by Reissner for finite rotations and stretching as well as shearing of plane beams. The motion is discretized by linear expansions of the global displacement components and the cross‐sectional rotation in two‐dimensional Euclidean space yielding a simple beam element with three degrees of freedom at the two nodes. The shear locking is reduced by selective integration in order to eliminate the spurious shear constraint similar to interdependent variable interpolation. The large rotation formulation is compared with two forms of moderate rotation theories which have been used in the past to develop the geometric stiffness properties for linear stability analysis of the so‐called Mindlin plate elements. The predictive value of different geometric stiffness approximations is assessed with several examples which range from the static and kinetic stability analysis of the classical Euler‐column to the large deflection problem of a clamped beam.

Aims to address the issues pertaining to dynamics of constrained finite rotations as a follow‐up from previous considerations in statics.

A conceptual approach is taken.

In this work the corresponding version of the Newmark time‐stepping schemes for the dynamics of smooth shells employing constrained finite rotations is developed. Different possibilities to choose the constrained rotation parameters are discussed, with the special attention given to the preferred choice of the incremental rotation vector.

The pertinent details of consistent linearization, rotation updates and illustrative numerical simulations are supplied.

The purpose of this paper is to improve opening performance of bi-directional rotation gas face seals by investigating the hydrodynamic effect of non-closed elliptical grooves.

A model of non-closed elliptical groove bi-directional rotation gas face seal is developed. The distribution of lubricating film pressure is obtained by solving gas Reynolds equations with the finite difference method. The program iterates repeatedly until the convergence criterion on the opening force is satisfied, and the sealing performance is finally obtained.

Non-closed elliptical groove presents much stronger hydrodynamic effect than the closed groove because of drop of the gas resistance flowing into grooves. Besides, the non-closed elliptical groove presents significant hydrodynamic effect under bi-directional rotation conditions, and an increase of over 40 per cent is obtained for the opening force at seal pressure 4.5 MPa, as same level as the unidirectional spiral groove gas seal. In the case of bi-directional rotation, the value of the inclination angle is recommended to set as 90° presenting a structure symmetry so as to keep best opening performance for both positive and reverse rotation.

A model of non-closed elliptical groove bi-directional rotation gas face seal is established. The hydrodynamic mechanism of this gas seal is illustrated. Parametric investigation of inclination angle and integrity rate is presented for the non-closed elliptical groove bi-directional rotation gas face seal.

This study is concerned with developing laminar flow of an incompressible, Newtonian fluid, having constant viscosity, rotating in circular and rectangular ducts that contain a 180° bend. The Reynolds number ranges from 100 to 400, the rotation number from 0 to 0.4, and the Dean number from 66 to 264. Positive and negative rotation modes are considered. The artificial compressibility method is used for the numerical calculations and new boundary conditions are developed for these flows. It is shown that rotation causes the secondary flow to occur in ducts of any geometry, and that the strength of the secondary flow in the bend due to both rotation and curvature decreases as compared to the no rotation case.

Damage detection of frame structures is important for guaranteeing the safety of people’s lives and property. Sensitivity analysis is an effective method for damage identification. The purpose of this paper is to conduct a sensitivity analysis of beam–column joint rotation angles for frame structures with limited flexural stiffness beams.

First, based on the D-value method and the assumption of inflection points, statically indeterminate frames were transformed to statically determinate structures, and the expressions of beam–column joint rotation angles were derived. Next, the sensitivity coefficients of beam–column joint rotation angles were obtained by taking the derivative of the expressions of beam–column joint rotation angles with respect to the linear stiffness of column. Finally, the expressions of the sensitivity coefficients were verified by a numerical example.

The analytical solutions of the sensitivity coefficients are in good agreement with finite element results. The results show that the beam–column joint rotation angles of damaged column decrease and those of intact columns within the same story increase when damage occurs.

In this study, the sensitivity coefficients of beam–column joint rotation angles with respect to the linear stiffnesses of columns were derived for frame structures. Based on the result of the sensitivity analysis, the relationship between the changes of beam–column joint rotation angles and damaged columns is revealed. The findings provide an important base to further detect damage of frame structures.

The purpose of this study is to explore the experience of selecting and engaging in biological sciences laboratory rotations from the perspective of doctoral students.

Within the socialization framework, this study uses a qualitative approach whereby 42 biological sciences students enrolled at highly selective US universities were interviewed in the first and second year of doctoral training about laboratory rotation experiences.

The study revealed how doctoral students used formal and informal information networks, explored research topics, struggled with funding concerns and learned about the social aspect of the laboratories in which they rotated.

While rotations are considered a signature pedagogy in the laboratory sciences, students’ experiences within them are understudied. This study offers new knowledge about what doctoral students experience while rotating that can be used to inform and improve rotation processes for both students and universities.