Flow and heat transfer modelling of an automotive engine lubrication system

This dissertation documents the thermodynamic and fluid mechanic analysis of an engine lubrication system. A comprehensive thermofluid computer model was developed to provide a flexible design analysis tool for the accurate prediction of oil pressures, flow rates and temperatures at any point within any lubrication system. Technical and financial support for the study was provided by Jaguar Cars. A comprehensive literature review revealed that the past research in this field had concentrated on either the thermofluid analysis of the lubrication system by engine testing, or the detailed analysis of individual components. A small number of computer models were developed for the flow analysis of the whole lubrication system. However, these models had limited heat transfer prediction capabilities, some requiring measured engine temperature data, and were not flexible enough to be employed as design tools. The objective of this study was to develop a flexible steady-state thermofluid design analysis tool, by integrating a flow analysis approach with a detailed analysis of the heat transfer within the engine block. Mathematical models of the thermofluid behaviour of the lubrication system components were developed and were implemented in a suite of FORTRAN computer programs which formed the design analysis package. A simple, linear flow model was initially developed to represent the system with a combination of laminar pipes, pumps, filters, journal bearings, crank-shaft transfer holes and cam bearing transfer holes. The linear program provided a rapid analysis tool, but the accuracy of the results were limited by the simplified flow characteristics of the system components. A more comprehensive and flexible non-linear flow model was developed, which solved for the unknowns with an iterative technique. Additional component models with non-linear flow characteristics, such as turbulent pipes, annular pipes, strainers, and oil coolers, were developed. The non-linear solution technique was proven to be robust and flexible and was subsequently used in all the analysis programs. The heat transfer to the oil within the pressurised part of the lubrication system is modelled by the heat transfer program. The engine block temperatures are calculated by the engine block program. This program accounts for the heat transfer to the oil splashed on to the internal surfaces of the engine. The engine geometry is represented by a series of block elements and modelled as a nodal resistance network. This capability has particular importance during the design stage, rapidly providing an estimate of the temperature profile through the engine block, results which were previously only available from expensive and slow FEA models. It was shown that both the Jaguar AJ6 and V8 engine lubrication systems could be analyzed in great detail. Engine tests showed that the predicted flow rates, pressures and temperatures were in excellent agreement with measured values. The overall accuracy of the results induced a high degree of confidence in the thermofluid model. The final analysis package was proven to be easy to use, robust, rapid, flexible and accurate. The design analysis package, developed during the course of this study, represents a unique stand-alone simulation tool which can rapidly analyze any engine lubrication system configuration. This package provides a valuable analysis tool which can be used to optimise system designs at the initial design stage and the diagnosis of performance problems during the development phase. Parametric studies can be easily carried out on the lubrication system and engine block configuration to identify areas which can enhance heat transfer to the oil. The steady-state analysis package forms an excellent platform for the development of a full transient model. This would allow a detailed analysis of the lubrication system during engine warm-up, with the aim of reducing engine emissions and determining minimum oil requirements

Internet Enhancement of the Role of Civil Society in Promoting the Rule of Law in Transitional States

The Internet has the potential to play a key role in the way civil society organizations promote the rule of law in transitional states.  In many states several barriers stand in the way of utilizing the Internet for this purpose.  Challenges that arise include technological deficits and poor infrastructure, socio-economic barriers, government hostility to open information, and civil society organizations unable to reach populations.  With the development of new technologies, and increased openness of information, civil society organizations will be better positioned to embrace the use of the Internet to promote the rule of law by helping citizens receive information, and facilitating communication between citizens and government

Finding Common Ground: Smart Growth and Affordable Housing

Low and Moderate Income (LMI) housing is an integral part of Smart Growth planning; however growth boundaries, taken alone, can constrain the supply of available land driving up housing costs. In many states, with more integrated growth management plans, these costs are made up for by incentives for more compact and integrated housing within well served, mixed use town and village centers; however, in Rhode Island the absence of real incentives and the slow pace of local reforms to outdated and exclusionary zoning policies has created some tension between Smart Growth and LMI housing advocates. In PART I of this study we developed at a way of measuring the smart growth potential of available land in communities throughout the state with particular attention to those towns outside of the Urban Service Boundary. These are often communities that are not served by municipal water and sewer infrastructure. These outlying areas are also among the fastest growing communities in the state and those with the lowest percentage of LMI Housing counting toward the state mandated 10% goal. Land Use 2025’s requirement that all projects in these outlying areas that receive state or federal funding be within identified Growth Centers means that, in some cases, there is a lack of suitable land for the development of the necessary LMI housing. This, coupled with the limited densities and increased costs of providing the needed septic systems, often make the cost of developing LMI housing in these areas prohibitive. In this study, we will look at the perceived tension between Smart Growth policies, such as those advocated in Land Use 2025 or the more recent RoadMap RI plans, and Fair Share housing legislation, in order identify possible remedies. Many of these issues are being taken up as part of the “RoadMAP RI” planning process; however, to the extent that part one of this study helped inform and advance the discussion of Growth Center planning in the state, this current effort will help ensure that we are more proactive in addressing important role of more integrated and diverse housing choices for all of the state’s inhabitants. This is critical to ensure expanding opportunities for those trapped in the cycle of poverty that has become entrenched in urban areas where concentrations of our nation’s most needy populations remain a persistent and costly challenge

Finding Common Ground: Smart Growth and Affordable Housing in Rhode Island

This presentation is a demonstration of the use of ESRI\u27s Weighted Overlay tool as a means of measuring smart growth potential of undeveloped and performance developed land within the state of Rhode Island. This exercise was undertaken in order to better understand the potential for conflicts between the State\u27s Growth Center initiative and its fair share Affordable (LMI) Housing goals. GIS has frequently been used to identify environmentally sensitive lands, but can also be used to measure the lands suitability for development based on clearly articulated smart growth goals and criteria. These goals are in alignment with best practices for the location of LMI housing; however, development in historic town centers in more rural communities can be extremely challenging

Interpretation of Spirometry in Saskatchewan First Nations Adults

Originally Published in: Mark E. Fenton, Brian L. Graham, Sanja Stanojevic, Lorna Whitford, and Laurie Ironstand. Interpretation of Spirometry in Saskatchewan First Nations Adults. Annals of the American Thoracic Society 2018;Vol. 15:1237-1239. DOI: 10.1513/AnnalsATS.201711-909RL Copyright © 2018 the American Thoracic Society The final publication is available at https://doi.org/10.1513/AnnalsATS.201711-909RL.Saskatchewan Health Research FoundationPeer ReviewedThe Canadian First Nations and Inuit communities bear a large burden of respiratory disease, with increased rates of smoking, respiratory infections, asthma, chronic obstructive lung disease, and hospitalizations (1). Identification of respiratory disease and classification has relied on spirometric reference values from white individuals, or in the case of the Global Lung Initiative (GLI) dataset, “other” (2), because there are no published reference values for Canadian First Nations individuals. Several studies have suggested that spirometric values for Canadian Inuit populations may be different from those for white populations (3–7), but these observations are not consistent (7–10). This study investigated whether lung function measured in Plains Cree adults differed from that expected in white adults. Part of the data reported in this letter was presented at the 2014 American Thoracic Society International Conference in abstract form (11)

Finding Common Ground Pt. II Growth Centers and Affordable Housing in Rhode Island

This is a full report of the research and GIS mapping analysis for communities in Rhode Island that are outside of the state\u27s Urban Service Boundary (areas served by water and sewer infrastructure). “Finding Common Ground Part I explored the rural Growth Centers in the State in order to begin to establish some basis for measuring their potential and relative performance according to the goals of Land Use 2025. Part II examines the relationship between smart growth and affordable (LMI) housing policies. This report was recognized by the Office of Statewide Planning and the RI Chapter of the American Planning Association. This research was made possible by a grant from the Roger Williams University Foundation to Promote Scholarship and Teaching

Tracking the global dispersal of a cosmopolitan insect pest, the peach potato aphid

<p>Abstract</p> <p>Background</p> <p>Global commerce and human transportation are responsible for the range expansion of various insect pests such as the plant sucking aphids. High resolution DNA markers provide the opportunity to examine the genetic structure of aphid populations, identify aphid genotypes and infer their evolutionary history and routes of expansion which is of value in developing management strategies. One of the most widespread aphid species is the peach-potato aphid <it>Myzus persicae</it>, which is considered as a serious pest on various crops in many parts of the world. The present study examined the genetic variation of this aphid at a world scale and then related this to distribution patterns. In particular, 197 aphid parthenogenetic lineages from around the world were analysed with six microsatellite loci.</p> <p>Results</p> <p>Bayesian clustering and admixture analysis split the aphid genotypes into three genetic clusters: European <it>M. persicae persicae</it>, New Zealand <it>M. persicae persicae </it>and Global <it>M. persicae nicotianae</it>. This partition was supported by <it>F</it>_STand genetic distance analyses. The results showed two further points, a possible connection between genotypes found in the UK and New Zealand and globalization of <it>nicotianae </it>associated with colonisation of regions where tobacco is not cultivated. In addition, we report the presence of geographically widespread clones and for the first time the presence of a <it>nicotianae </it>genotype in the Old and New World. Lastly, heterozygote deficiency was detected in some sexual and asexual populations.</p> <p>Conclusion</p> <p>The study revealed important genetic variation among the aphid populations we examined and this was partitioned according to region and host-plant. Clonal selection and gene flow between sexual and asexual lineages are important factors shaping the genetic structure of the aphid populations. In addition, the results reflected the globalization of two subspecies of <it>M. persicae </it>with successful clones being spread at various scales throughout the world. A subspecies appears to result from direct selection on tobacco plants. This information highlights the ultimate ability of a polyphagous aphid species to generate and maintain ecologically successful gene combinations through clonal propagation and the role of human transportation and global commerce for expanding their range.</p

Identification of individuals with gonorrhoea within sexual networks: a population-based study.

BACKGROUND: Molecular typing of Neisseria gonorrhoeae and contact tracing provide a combined approach for analysis of sexual networks in metropolitan areas, although there are some difficulties in application. Our aim was to examine the application of high-throughput molecular approaches that can identify individuals in linked sexual networks. METHODS: We characterised 2045 isolates of N gonorrhoeae from patients presenting at 13 major sexually transmitted infection clinics in London, UK, between June 1 and Nov 30, 2004. All isolates were assigned a sequence type (strain) on the basis of the sequences of internal fragments of two highly polymorphic loci, por and tbpB. These types were matched to demographic and behavioural data obtained at the clinic for each patient. We assessed the congruence in the demographic and behavioural characteristics of individuals infected with the same strain. FINDINGS: We identified 21 prevalent strains in this diverse gonococcal population, each infecting between 20 and 124 individuals. Seven of these strains were predominantly from men who have sex with men; the remaining 14 were predominantly from heterosexual people. No differences were recorded between the strains associated with men who have sex with men in the demographic or behavioural characteristics of infected individuals. By contrast, significant differences in age (p<0.0001), ethnicity (p=0.001), proportion of women (p=0.01), and HIV status (p=0.03) were noted between the 14 prevalent heterosexual-associated strains. Heterosexuals with strains not shared by others in the sample were significantly older (p=0.0005) and more likely to have had sex outside the UK (p<0.0001) than those sharing a strain with at least one other. INTERPRETATION: The discriminatory high throughput strain characterisation method applied here identified localised transmission networks and suggests little bridging between networks of men who have sex with men and heterosexual networks

Pathogen Interactions, Population Cycles, and Phase Shifts

Interspecific pathogen interactions can profoundly affect pathogen population dynamics and the efficacy of control strategies. However, many pathogens exhibit cyclic abundance patterns (e.g. seasonality) and temporal asynchrony between interacting pathogens has the potential to reduce the impact of those interactions. Here we use an extension of our previously published model to investigate the effects of cyclic abundance patterns on pathogen interaction. We demonstrate that for interactions mediated through host immunity, immune memory can maintain the impact of an interaction even when the effector pathogen abundance is low or the pathogen is absent. Paradoxically, immune memory can result in pathogens interacting more strongly when temporally out of phase. We find that interactions between species can not only alter pathogen abundance but can also result in changes to the temporal pattern of the affected species. We further demonstrate that this phenomenon may be observed in a natural host / pathogen data set. Given that there is both a continuing debate as to the relevance of pathogen interactions in natural systems and increasing concern regarding treatment of coinfections of veterinary and medical importance, both the discovery of this measurable shift in cycle in the empirical data and the mechanism by which we identified the shift are important. Finally, as the model structure used here is analogous to simple predator-prey system models we also consider the consequences of these findings in the context of that system