Enhanced Vertical Inhomogeneity in Turbulent Rotating Convection

In this Letter we report experimental evidence that rotation enhances vertical inhomogeneity in turbulent convection, in spite of the increased columnar flow ordering under rotation. Measurements using stereoscopic particle image velocimetry have been carried out on turbulent rotating convection in water. At constant Rayleigh number Ra=1.11×109 several rotation rates have been used, so that the Rossby number takes values from Ro=[infinity] (no rotation) to 0.09 (strong rotation). The three-component velocity data, obtained at two vertical positions, are used to investigate the anisotropy of the flow through the invariants of the Reynolds-stress anisotropy tensor and the Lumley triangle, as well as to correlate the vertical velocity and vorticity. In the center plane rotation causes the turbulence to be “rodlike,” while closer to the top plate a trend toward isotropy is observed

Heat transfer in turbulent rotating convection

No abstract

Heat flux intensification by vortical flow localization in rotating convection

The effect of rotation on turbulent convective flow between parallel plates has been assessed with direct numerical simulations. With increasing rotation-rate an interesting transition is observed in the vertical-velocity skewness. This transition indicates a localization of motion directed away from the wall and correlates well with changes observed in the heat flux, as well as in the thermal and viscous boundary layer thicknesses. The formation of localized intense vortical structures provides for intensified vertical heat transport through Ekman pumping. At higher rotation-rates this is counteracted by the inhibition of vertical motion by rotation as expressed in the geostrophic thermal-wind balance

A model for vortical plumes in rotating convection

In turbulent rotating convection a typical flow structuring in columnar vortices is observed. In the internal structure of these vortices several symmetries are approximately satisfied. A model for these columnar vortices is derived by prescribing these symmetries. The symmetry constraints are applied to the Navier¿Stokes equations with rotation in the Boussinesq approximation. It is found that the application of the symmetries results in a set of linearized equations. An investigation of the linearized equations leads to a model for the columnar vortices and a prediction for the heat flux (Nusselt number) that is very appropriate compared to the results from direct numerical simulations of the full governing equation

The Role of Emotional Experiences in Commitment Development in Internship Students

In this study I address the relation between real-time experiences and vocational identity development in psychology students during their practical internship. By means of a multi-method approach I aimed to shed light on the role of salient emotional experiences in commitment development, and on the characteristics of these experiences. In a diary study internship students reported every week about their most relevant experience. For each student the most salient positive and negative emotional experience was selected. Most positive and negative experiences concerned competence-related issues. Salient emotional experiences were related to commitment change for a prolonged period of time. In line with the theoretical models, salient positive emotional experiences enhance the commitment strength, and salient negative emotional experiences reduce the strength. However, many experiences include different characteristics. In particular, negative emotional experiences are characterized by a diversity of both positive and negative characteristics.</p

The relation between vocational commitment and need fulfillment in real time experiences in clinical internships

This study concerns the question how specific characteristics of real-time experiences relate to commitment change. The focus is on the real-time fulfillment of the basic needs: the need for competence, for relatedness and for autonomy. The research question was: “What is the relation between real time need fulfillment and commitment in psychology students during their practical internships?” The participants were 56 master students who did a five-month clinical internship in psychology. The participants wrote at least 19 weekly diary reports (in a period of 5 months) about the most important experience in their internship in that week, and in addition they filled in a short questionnaire. With a linear mixed model analysis, the relation was analyzed between need fulfillment and commitment on an individual and on a group level. The basic needs were found to be a relevant characteristic of experiences: need fulfillment or need frustration was described in by far most experiences. Experiences with a positive need fulfillment were related to higher levels of commitment strength than experiences that concerned frustration of need fulfillment, or that did not report need fulfillment. This pattern of relations was found in 90% of the individual participants. The experiences of the atypical 10% of the participants reflected a non-optimal relationship with their internship or supervisor