Computational solutions are presented for flows ranging from incompressible viscous flows to inviscid transonic flows. The viscous flow problems are solved using the incompressible Navier-Stokes equations while the inviscid solutions are attained using the full potential equation. Results for the viscous flow problems focus on turbulence modeling when separation is present. The main focus for the inviscid results is the development of an unstructured solution algorithm. The subject dealing with turbulence modeling for separated flows is discussed first. Two different test cases are presented. The first flow is a low-speed converging-diverging duct with a rapid expansion, creating a large separated flow region. The second case is the flow around a stationary hydrofoil subject to small, oscillating hydrofoils. Both cases are computed first in a steady state environment, and then with unsteady flow conditions imposed. A special characteristic of the two problems being studied is the presence of strong adverse pressure gradients leading to flow detachment and separation. For the flows with separation, numerical solutions are obtained by solving the incompressible Navier-Stokes equations. These equations are solved in a time accurate manner using the method of artificial compressibility. The algorithm used is a finite volume, upwind differencing scheme based on flux-difference splitting of the convective terms. The Johnson and King turbulence model is employed for modeling the turbulent flow. Modifications to the Johnson and King turbulence model are also suggested. These changes to the model focus mainly on the normal stress production of energy and the strong adverse pressure gradient associated with separating flows. The performance of the Johnson and King model and its modifications, along with the Baldwin-Lomax model, are presented in the results. The modifications had an impact on moving the flow detachment location further downstream, and increased the sensitivity of the boundary layer profile to unsteady flow conditions. Following this discussion is the numerical solution of the full potential equation. The full potential equation assumes inviscid, irrotational flow and can be applied to problems where viscous effects are small compared to the inviscid flow field and weak normal shocks. The development of a code is presented which solves the full potential equation in a finite volume, cell centered formulation. The unique feature about this code is that solutions are attained on unstructured grids. Solutions are computed in either two or three dimensions. The grid has the flexibility of being made up of tetrahedra, hexahedra, or prisms. The flow regime spans from low subsonic speeds up to transonic flows. For transonic problems, the density is upwinded using a density biasing technique. If lift is being produced, the Kutta-Joukowski condition is enforced for circulation. An implicit algorithm is employed based upon the Generalized Minimum Residual method. To accelerate convergence, the Generalized Minimum Residual method is preconditioned. These and other problems associated with solving the full potential equation on an unstructured mesh are discussed. Results are presented for subsonic and transonic flows over bumps, airfoils, and wings to demonstrate the unstructured algorithm presented here. / Ph. D.

A hazardous and not fully understood aeroelastic phenomenon is the transonic dip,the decrease in flutter dynamic pressure that occurs for most aircraft configurationsin transonic flows. The difficulty of predicting this phenomenon forces aircraft manufacturersto run long and costly flight test campaigns to demonstrate flutter-free behaviourof their aircraft at transonic Mach numbers.In this project, subsonic and transonic flutter calculations for the KTH-NASA genericfighter research model have been performed and compared to existing experimentalflutter data from wind tunnel tests performed at NASA Langley in 2016. For the fluttercalculations, industry-standard linear panel methods have been used together with afinite element model from NASTRAN.Further, an alternative approach for more accurate transonic flutter predictions usingthe full-potential solver Phi has been investigated. To predict flutter using this newmethodology a simplified structural model has been used together with aerodynamicmeshes of the main wing. The purpose of the approach was to see if it was possibleto find a method that was more accurate than panel methods in the transonic regimewhilst still being suitable for use during iterative design processes.The results of this project demonstrated that industry-standard linear panel methodssignificantly over-predict the flutter boundary in the transonic regime. It was alsoseen that the flutter predictions using Phi showed potential, being close to the linearresults for the same configuration as tested in Phi. For improved transonic accuracy inPhi, an improved transonic flow finite element formulation could possibly help .Another challenge with Phi is the requirement of an explicit wake from all liftingsurfaces in the aerodynamic mesh. Therefore, a method for meshing external storeswith blunt trailing edges needs to be developed. One concept suggested in this projectis to model external stores in "2.5D", representing external stores using airfoils withsharp trailing edges. / Ett farligt och inte helt utrett aeroelastiskt fenomen är den transoniska dippen, minskningeni dynamiska trycket vid fladder som inträffar för de flesta flygplan i transoniskaflöden. Svårigheten i att prediktera detta fenomen tvingar flygplanstillverkare attbedriva tidskrävande och kostsam flygprovsverksamhet för att demonstrera att derasflygplan ej uppvisar fladderbeteende i transonik inom det tilltänkta användningsområdet.I detta projekt har fladderberäkningar genomförts i både underljud och transonikför en generisk stridsflygplansmodell i skala 1:4 ämnad för forskning, byggd som ettsamarbete mellan KTH och NASA. Beräkningarna har också jämförts med fladderresultatfrån vindtunnelprov genomförda vid NASA Langley under sommaren 2016. Förfladderberäkningarna har industri-standarden linjära panelmetoder används tillsammansmed en befintlig finit element modell för användning i NASTRAN.Vidare har ett alternativt tillvägagångssätt för att förbättra precisionen i transoniskafladderresultat genom att använda potentiallösaren Phi undersökts. En förenkladstrukturmodell har använts tillsammans med aerodynamiska nät av huvudvingen föratt prediktera fladder. Syftet med denna metodik var att undersöka om det var möjligtatt hitta en metod som i transoniska flöden var mer exakt än panelmetoder men somfortfarande kunde användas i iterativa design processer.Resultaten från detta projekt visade att linjära panelmetoder, som de som används iindustrin, är signifikant icke-konservativa gällande fladdergränsen i transonik. Resultatenfrån Phi visade potential genom att vara nära de linjära resultaten som räknadesfram med hjälp av panelmetoder för samma konfiguration som i Phi. För ökad transonisknoggrannhet i Phi kan möjligen en förbättrad transonisk element-formuleringhjälpa.En annan utmaning med Phi är kravet på en explicit vak från alla bärande ytor idet aerodynamiska nätet. Därför behöver det utvecklas en metodik för nätgenereringav yttre laster med trubbiga bakkanter. Ett koncept som föreslås i denna rapport är attmodellera yttre laster i "2.5D", där alla yttre laster beskrivs genom att använda vingprofilermed skarpa bakkanter.

Classical Continuous System Simulation (CSS) is restricted to modelling continuous flows, and therefore, cannot correctly realise a conceptual model with discrete objects. The development of Full Potential CSS solves this problem by (1) handling discrete quantities as discrete and continuous matter as continuous, (2) preserving the sojourn time distribution of a stage, (3) implementing attributes correctly, and (4) describing different types of uncertainties in a proper way. In order to apply Full Potential CSS a new software, StochSD, has been developed. This thesis evaluates StochSD's ability to model Full Potential CSS, where the points 1-4 above are included. As a test model a well-defined conceptual epidemic model, which includes all aspects of Full Potential CSS, was chosen. The study was performed by starting with a classical SIR model and then stepwise add the different aspects of the Conceptual Model. The effects of each step were demonstrated in terms of size and duration of the epidemic. Finally, the conceptual model was also realised as an Agent Based Model (ABM). The results from 10 000 replications each of the CSS and ABM models were compared and no statistical differences could be confirmed. The conclusion is that StochSD passed the evaluation.

We describe the rare-earth elements using the Hubbard I approximation. We show that the theory reproduces the cohesive properties, like the volume and bulk modulus, and we find an excellent agreement between theory and experiment for the (inverse) photo emission spectra of the valence band. In addition we reproduce the spin and orbital moments of these elements. This licentiate thesis contains an introduction to the cohesive, magnetic and spectral properties of the rare-earth elements, to density functional theory and to density functional theory in combination with dynamical mean-field theory within the Hubbard I approximation. We also focus on some technical details, e.g. the optimal basis used in the electronic structure code and the role of charge self-consistency in properly describing the valence electrons.

The National Commission of Special Needs in Education and Training (NCSNET) Document (1997) which portrays the new Education Policy in South Africa. clearly states that one of the crucial outcomes is that all possible barriers to learning must be eliminated so that all learners are able to actualise their full potential. Inclusive education, as embedded within the Education Policy, is regarded as an approach which will allow learners to actualise their full potential. This study is a critical reflection on whether inclusive education is practised in primary schools in the Thohoyandou area. The research findings indicated that inclusive education is not practised in the Thohoyandou area. A major factor or barrier in this regard is that teachers and principals are not empowered in terms ofknowledge to practise inclusive education. Other factors acting as barriers to the implementation of inclusive education are that the school buildings do not cater for physically and visually impaired learners as well as the attitudes of teachers, parents and peers are inclined to be negative towards learners experiencing barriers to learning. The community should also be educated and empowered to assist and understand these learners, who will become the future members of the community, more effectively, As inclusive education is one of the means whereby all learners are given the opportunity to actualise their full potential, these barriers must be addressed so that inclusive education can be practised in all primary schools in the Thohoyandou area. A few strategies to implement inclusive education in the Thohoyandou area are suggested by the researcher. / Educational Studies / M. Ed. (Special Needs Education)

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This thesis aimed to investigate generational differences in the frequency and importance of meaningful work in employees based on the 7 facets of the Map of Meaning. Hypotheses were tested through Analysis of Variance of secondary data. 395 participants self-reported levels of meaningful work on the Comprehensive Meaningful Work Scale. Results indicated that Generation Y had significantly lower levels of meaningful work. Generation Y had significantly lower levels of Unity (importance), Serving (frequency and importance), Expressing full potential (frequency), Reality (frequency and importance) and Inspiration (frequency). Significant differences occurred mainly between Generation Y and Baby boomers, with some significant differences between Generation Y and Generation X and no significant differences between Generation X and Baby boomers. Results showed that overall frequency and importance levels were significantly lower for Generation Y. Overall frequency levels were lower than overall importance levels, which suggests that employees’ desire for meaningful work may not be satisfied. In light of this evidence, it is suggested that to improve organisational outcomes such as engagement, retention and performance, managers should provide opportunities for employees to engage in meaningful work with particular focus on Generation Y. Employees themselves should take responsibility to find meaning in their own work and life because engagement in meaningful activities can lead to satisfaction, belonging, fulfilment and a better understanding of one’s purpose in life.

The National Commission of Special Needs in Education and Training (NCSNET) Document (1997) which portrays the new Education Policy in South Africa. clearly states that one of the crucial outcomes is that all possible barriers to learning must be eliminated so that all learners are able to actualise their full potential. Inclusive education, as embedded within the Education Policy, is regarded as an approach which will allow learners to actualise their full potential. This study is a critical reflection on whether inclusive education is practised in primary schools in the Thohoyandou area. The research findings indicated that inclusive education is not practised in the Thohoyandou area. A major factor or barrier in this regard is that teachers and principals are not empowered in terms ofknowledge to practise inclusive education. Other factors acting as barriers to the implementation of inclusive education are that the school buildings do not cater for physically and visually impaired learners as well as the attitudes of teachers, parents and peers are inclined to be negative towards learners experiencing barriers to learning. The community should also be educated and empowered to assist and understand these learners, who will become the future members of the community, more effectively, As inclusive education is one of the means whereby all learners are given the opportunity to actualise their full potential, these barriers must be addressed so that inclusive education can be practised in all primary schools in the Thohoyandou area. A few strategies to implement inclusive education in the Thohoyandou area are suggested by the researcher. / Educational Studies / M. Ed. (Special Needs Education)