Prediction of flow and combustion in IC engines remains a challenging task. Traditional Reynolds Averaged Navier Stokes (RANS) methods and emerging Large Eddy Simulation (LES) techniques are being used as reliable mathematical tools for such predictions. However, RANS models have to be further refined to make them more predictive by eliminating or reducing the requirement for application based fine tuning. LES holds a great potential for more accurate predictions in engine related unsteady combustion and associated cycle-tocycle variations. Accordingly, in the present work, new advanced CFD based flow models were developed and validated for RANS and LES modelling of turbulent premixed combustion in SI engines. In the research undertaken for RANS modelling, theoretical and experimental based modifications have been investigated, such that the Bray-Moss-Libby (BML) model can be applied to wall-bounded combustion modelling, eliminating its inherent wall flame acceleration problem. Estimation of integral length scale of turbulence has been made dynamic providing allowances for spatial inhomogeneity of turbulence. A new dynamic formulation has been proposed to evaluate the mean flame wrinkling scale based on the Kolmogorov Pertovsky Piskunow (KPP) analysis and fractal geometry. In addition, a novel empirical correlation to quantify the quenching rates in the influenced zone of the quenching region near solid boundaries has been derived based on experimentally estimated flame image data. Moreover, to model the spark ignition and early stage of flame kernel formation, an improved version of the Discrete Particle Ignition Kernel (DPIK) model was developed, accounting for local bulk flow convection effects. These models were first verified against published benchmark test cases. Subsequently, full cycle combustion in a Ricardo E6 engine for different operating conditions was simulated. An experimental programme was conducted to obtain engine data and operating conditions of the Ricardo E6 engine and the formulated model was validated using the obtained experimental data. Results show that, the present improvements have been successful in eliminating the wall flame acceleration problem, while accurately predicting the in-cylinder pressure rise and flame propagation characteristics throughout the combustion period. In the LES work carried out in this research, the KIVA-4 RANS code was modified to incorporate the LES capability. Various turbulence models were implemented and validated in engine applications. The flame surface density approach was implemented to model the combustion process. A new ignition and flame kernel formation model was also developed to simulate the early stage of flame propagation in the context of LES. A dynamic procedure was formulated, where all model coefficients were locally evaluated using the resolved and test filtered flow properties during the fully turbulent phase of combustion. A test filtering technique was adopted to use in wall bounded systems. The developed methodology was then applied to simulate the combustion and associated unsteady effects in Ricardo E6 spark ignition engine at different operating conditions. Results show that, present LES model has been able to resolve the evolution of a large number of in-cylinder flow structures, which are more influential for engine performance. Predicted heat release rates, flame propagation characteristics, in-cylinder pressure rise and their cyclic variations are also in good agreement with measurements.

Two-stroke poppet-valved engines may combine the high power density of two - stroke engines and the low emissions of poppet-valved engines. A two-stroke diesel engine can generate the same power as a four-stroke engine of the same size, but at higher (leaner) air/fuel ratios. Diesel combustion at high air/fuel ratios generally means hydrocarbons, soot and carbon monoxide are oxidised more completely to water and carbon dioxide in the cylinder, and the opportunity to increase the rate of exhaust gas recirculation should reduce the formation of nitrogen oxides (NOx). The concept is being explored as a means of economically modifying diesel engines to make them cleaner and/or more powerful. This study details the application of two computational models to this problem. The first model is a relatively simple thermodynamic model created by the author capable of rapidly estimating the behaviour of entire engine systems. It was used to estimate near-optimum engine system parameters at single engine operating points and over a six-mode engine cycle. The second model is a detailed CFD model called KIVA-ERC. It is a hybrid of the KIVA engine modelling package developed at the Los Alamos National Laboratory and combustion and emissions subroutines developed at the University of Wisconsin-Madison Engine Research Center. It was used for detailed scavenging and combustion simulations and to provide estimates of emissions levels. Both models were calibrated and validated for four-stroke cycle operation using experimental data. The thermodynamic model was used to provide initial and boundary conditions to the KIVA-ERC model. Conversely, the combustion simulations were used to adjust zero-dimensional combustion correlations when experimental data was not available. Scavenging simulations were performed with shrouded and unshrouded intake valves. A new two-zone scavenging model was proposed and validated using multidimensional scavenging simulations. A method for predicting the behaviour of the two-stroke engine system based on four-stroke data has been proposed. The results using this method indicate that a four-stroke diesel engine with minor modifications can be converted to a two-stroke cycle and achieve substantially the same fuel efficiency as the original engine. However, emissions levels can not be predicted accurately without experimental data from a physical prototype. It is therefore recommended that such a prototype be constructed, based on design parameters obtained from the numerical models used in this study.

Kiva is an international non-governmental organization that competes for funds with others in the field. As a consequence, some special relationships and dependencies are formed. This paper argues that among the most significant ones are the representations of borrowers on Kiva’s online lending platform. The work hypothesizes that while Kiva has the potential to create a friendly environment where both participatory and problem-solving style of communication is encouraged, the organization turns out to be a development factor with international importance which inevitably influences the stereotyping of individuals from the Global South. In that sense, the representations of people from the Global South on Kiva’s online platform seem to continue a well-established tradition of Western-centrism, thus admitting further stereotyping also of the audience from the Global North.Through the lens of postcolonial theory and critical discourse analysis as research methods, the research questions and the hypotheses of the paper aim at contributing to the current debates on the existing power relations between the Global South and North by providing information on: how are people in need represented through profiles of single parents as borrowers on Kiva’s website; do representations of single parents contribute to the process of creating stereotypes; what is the role of microfinance in development.By using the most recent data from Kiva's online lending platform, the work aims to present evidence on the stereotypization of representations of a specific sample group of borrowers – individual single parents. While taking into consideration Kiva's ambition towards creating cooperation based on reciprocal dignity, the paper provides some possible interpretations of the way individuals in need are portrayed. It aims to come to the aid of individuals who have interests in the development field, who may want to rethink fundraising strategies involving both visual and textual representations of people, especially in the field of online lending.

The archaeofaunal remains left by the Ancestral Puebloan people of Goodman Point Unit provides a valuable, yet underutilized resource into pit structure function. This thesis explores temporal changes in pit structure use and evaluates if a final feast occurred during a kiva decommissioning. The results from zooarchaeological analyses of a pithouse and two great kivas suggest that changes in pit structures at Goodman Point mimic the regional trend toward specialization until late Pueblo III. Cross-cultural studies on feasts, southwest ethnographies and previous zooarchaeological work established methods for identifying a feast. The analysis of differences in faunal remains from a great kiva and multiple room block middens imply that the remains in the kiva were from a final feast prior to a decommissioning ceremony and were not fill. Spatially and temporally the great kiva appears to be a unique, specialized structure in the cultural development of the Goodman Point community.

This project examines a new and growing form of international development fundraising, which constructs and packages development as a product of consumption in order to achieve its goals of awareness and fundraising. These efforts involve the use of a new set of marketing tools, technologies, languages, and tactics to encourage the sale of the development cause. The commodification of development activities within fundraising efforts ultimately poses an important quandary in terms of the effects that such ventures have upon public engagement and reception of international development. As such, this thesis explores the implications of such efforts for social justice in terms of the ways in which people’s perceptions of their own involvement and the causes of which they are a part are shifted. In order to more closely analyze such activities, the organizations (RED) and Kiva were chosen to act as case studies of both corporate and non-for-profit endeavours.

Application of supply chain management is still relatively recent practice, but it's importance is growing over time. Today, in the era of customer centricity, in order to become competitive firms shouldn't avoid collaboration with it's supply chain partners. Purpose of my thesis was to find out how supply chain management can contribute to building relationship with customers, who are the basis of any existing company. First part summarizes knowledge about supply chain, compeptitive strategies, customers, types of supply chains and customer relationship management. Particular part is dedicated to customer service and how supply chain management can contribute to it's improving. It describes also what meaning has customer service for future competitiveness. In second part, I presented the case of Zappos.com. E-retailer, which aligning entire functional strategies and whole supply chain to common strategic purpose managed to build excellent relationship with it's customers.

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